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HomeMy WebLinkAboutSEPA EPIC-35-87 - NEW LINK - SOUTHCENTER PARKWAY AND ANDOVER PARK WEST ARTERIAL (SOUTH 168TH STREET)NEW LINK ARTERIAL BETWEEN SOUTHCENTER PARKWAY & ANDOVER PARK WEST S0. 168T" STREET EPIC -35 -87 City of Tukwila 6200 Southcenter Boulevard Tukwila Washington 98188 (206) 433 -1800 Gary L. VanDusen, Mayor MEMORANDUM TO: All ,I��sted Parties M: FRO. /��/ Beeler, SEPA Responsible Official DATE. une 3, 1987 SUBJECT: SOUTH 168TH STREET DRAFT ENVIRONMENTAL IMPACT STATEMENT (DEIS) This DEIS was prepared pursuant to Chapter 197 -11, Washington Administra- tive Code, and is herewith being distributed for public review and comment. The key issues are wetlands, traffic circulation, and land use parking impacts. Alternatives to the proposal range from no action and a continued deterioration of traffic circulation characteristics (Figures 23 and 24) to a four -lane alternative with maximum loss of 2.8 acres of wetland and land use impacts (Table 1). The engineering basis for this DEIS is provided in a separate document entitled "South 168th Street - Design Report ", on file at the City of Tukwila Public Works Department. This DEIS includes the relevant informa- tion from that report. Written comments on this DEIS are due by July 3, 1987. VU /sjn attachment Ey 1 c_ DRAFT ENVIRONMENTAL IMPACT STATEMENT FOR SOUTH 168TH STREET City of Tukwila Department of Public Works King County, Washington Prepared pursuant to The State Environmental Policy Act of 1971 Revised Code of Washington 43.21c and SEPA Rules, Effective April 4, 1984 Chapter 197 -11, Washington Administrative Code Date of Issue: Date Comments Due: and City of Tukwila Ordinance #1331 As amended by Ordinance #1344 June 3, 1987 July 3, 1987 Responsible Official Project Title Proposed Action Project Location Action Sponsor Implementation Date Lead Agency Contact Person Responsible Official Licenses and Permits Required FACT SHEET South 168th_Street Construction of a new link arterial is proposed between Southcenter Parkway and Andover Park West in the Commercial Industrial. District of the City of Tukwila. A three lane roadway, two four lane roadways and a no- action alternative are reviewed. The proposed roadway is located in the north half of Section 26, Township 23, Range 4, City of Tukwila. It is generally bordered by what is commonly called Tukwila Pond to the north, Andover Park West to the east, Southcenter Parkway to the west, and a Union Pacific Railway spur to the south. City of Tukwila Department of Public. Works 6200 Southcenter Boulevard Tukwila, Washington 98188 Spring, 1988 City of Tukwila Mr. Nernon M. Umetsu, Associate Planner Department of Planning City of Tukwila 6200 Southcenter Boulevard Tukwila, Washington 98188 Mr. L. Rick Reeler Planning Director City of Tukwila Washington State Department of Game • Hydraulic Project Approval (HPA) City of Tukwila, Department of Public Works • Street Use Permit • Hauling Permit City of Tukwila, Building Department • Grading Permit Union Pacific Railroad • Driveway Crossing of Railroad Plain Lead Track Principal Contrihutors Date of Issue of Draft EIS Date Comments Due Mail Comments to Location of Background Material Puget Sound Power and Light • Revised Easements U.S. Army Corps of Engineers • Section 404 Permit EIS and Design Report Authors Entranco Engineers, Inc. Lake Washington Park Building 5808 Lake Washington Boulevard Kirkland, Washington 98033 Biological Consultant Independent Ecological Services 1514 Muirhead Olympia, Washington 98502 June 3, 1987 July 3, 1987 Mr. Vernon M. Umetsu, Associate Planner City of Tukwila 6200 Southcenter Boulevard Tukwila, Washington 98188 City Hall City of Tukwila 6200 Southcenter Boulevard Tukwila, Washington 98188 (206) 433 -1858 Tukwila Library 14475 - 59th Avenue South Tukwila, Washington 98188 (206) 244 -5140 Entranco Engineers, Inc. Lake Washington Park Building 5808 Lake Washington Boulevard N.E. Kirkland, Washington 98033 (206) 827 -1300 Cost of Draft EIS $10.00 ii TABLE30F CONTENTS Page FACT SHEET LIST OF FIGURES iv LIST OF TABLES vi I. SUMMARY Purpose and Brief Description of Action 1 Description of Alternatives 3 Major Environmental Impacts and Mitigating Measures . . 4 Special Issues of Concern 4 II. ALTERNATIVES INCLUDING THE PROPOSED ACTION Purpose and Need for Action 9 Project Site and Environmental Considerations 10 Alternatives 12 III. AFFECTED ENVIRONMENT, SIGNIFICANT IMPACTS, AND MITIGATION MEASURES Natural Environment Earth 29 Air 33 Water 37 Plants and Animals 40 Built Environment Noise 57 Land Use 61 Transportation 76 Aesthetics 92 Utilities 96 REFERENCES 101 DISTRIBUTION LIST 103 APPENDICES A. Scoping Comments B. Biological Evaluation of Tukwila Pond C. City of Tukwila Condemnation Procedures iii LIST OF FIGURES Figure Page 1 Vicinity Map 2 2 Project Area 5 3 Typical Roadway Sections 15 4 Alternative A Alignment 16 5 Alternative A Plan - Station 5 +00 to 15 +00 17 6 Alternative A Plan - Station 15 +00 to 25 +02 18 7 Alternative B Alignment 19 8 Alternative B Plan - Station 5 +00 to 15 +00 20 9 Alternative B Plan - Station 15 +00 to 25 +02 21 10 Alternative C Alignment 22 11 Alternative C Plan - Station 5 +00 to 15 +00 23 12 Alternative C Plan - Station 15 +00 to 25 +02 24 13 Alternative fl Alignment 25 14 Alternative D Plan - Station 5 +00 to 15 +00 26 15 Alternative D Plan - Station 15 +00 to 25 +02 2.7 16 Soils Profile 31 17 Project Site and Vicinity Drainage 38 18 Tukwila Pond Habitat 43 19 Roadway and Landscape Proposal for Wetland Mitigation . 55 20 City of Tukwila Zoning 63 21 Existing Traffic Conditions 79 22 Existing Transit Service 83 23 1990 Traffic Conditions Without Project 87 iv LIST OF FIGURES (Continued) Figure Page 24 1990 Traffic Conditions With Project 88 25 Projected Volumes on South 168th Street 91 26 View from Service Drive Off Southcenter Parkway, Looking East 93 27 View from Railroad Tracks South of Tukwila Pond, Looking West 94 28 View from Access Point of Proposed South 168th Street on Andover Park West, Looking South 94 29 Typical Landscape Section 97 v LIST OF TABLES Table. Page 1 Impact Summary of South 168th Street Project 7 2 Sound Levels and Human Response 58 3 U.S. Environmental Protection Agency Noise Impact Guidelines 59 4 Setback and Landscape Area Requirements 64 5 Approximate Right -of -Way Requirements 70 6 Building Setbacks Under Each Action Alternative 71 7 Parking Space Impacts 73 8 Maximum Impact to Development Potential Resulting From Parking Loss 75 9 Existing Roadway Characteristics 77 10 Relevant Projects in City of Tukwila's Six -Year 1985 -1990 Transportation Improvement Program 78 11 Level of Service and Average Vehicle Delay Time for Intersections of Strander Boulevard with Southcenter Parkway and Andover Park West 81 12 Accident Data Summary 82 vi SECTION I SUMMARY SUMMARY PURPOSE AND BRIEF DESCRIPTION OF ACTION The portion of Tukwila, Washington hounded by I -405 , I -5,- the Green River and South 180th Street (Figure 1) is a mix of commercial and industrial developments, including Southcenter-.Mall and numerous smaller shopping centers, office complexes and warehouses. This area is known as Tukwila's "central business district" (CBD). The existing street system has formed a "superblock ", bordered by Southcenter Parkway, Strander Boulevard, Andover Park West, and South 180th Street. The east -west running Strander Boulevard and South 180th Street are the only links between Southcenter Parkway and Andover Park West for a distance of one mile. The interstate freeway system and Green River provide physical barriers which also concentrate traffic on the "superblock" streets. The City of Tukwila has investigated means of relieving congestion on both Strander Boulevard and South 180th Street, and at all four intersections. Two of the intersections currently operate at an acceptable level of service for urban areas (LOS A -D, Figure 21). These included Southcenter Parkway /South 180th and Andover Park West /South 180th. In contrast, the intersections of Southcenter Parkway /Strander Boulevard and Andover Park West /Strander Boulevard operate below acceptable levels during noon peak hour traffic (LOS E and F, respectively). Existing or projected 1990 volumes without the project show a level of service of E or F at the following intersections: Southcenter Parkway/ Strander Boulevard, Southcenter Parkway /South 180th, and Andover Park West /Strander Boulevard (Figures 21 and 23). Level of service F is characterized by extreme congestion and long delays. The superblock configuration also hinders east -west travel, and there- fore access to businesses and services both within and outside the block. The City of Tukwila's Six -Year Transportation Improvement Program for 1987 -1992 includes two east -west cross streets through the superblock on its prioritized list of improvements: • No. 1 is the proposed extension of Minkler Boulevard approximately halfway down the superblock. An Environmental Impact Statement (City of Tukwila, 1986) has been prepared for this project and the review process completed. 1 '.4 Or -, SNOHOUISH COUNTY 1 KING COUNTY RENTON PROJECT SITE TUKWILA •KENT • AUBURN Key Plan • :TUKWILA *CITY '11MITS I O • • .e CITY OF TUKWILA, WASHINGTON ENTRANCO ENGINEERS, INC. NORTH SCALE: 1" =.1600' Figure 1 VICINITY MAP 2 • No. 9 is South 168th Street, a proposed new link arterial, and the subject of this Environmental Impact Statement. The proposed 168th Street is a 2,000 -foot collector arterial joining Southcenter Parkway and Andover Park West at T- intersections. The purpose of the proposed new roadway is to: • Reduce existing and projected traffic congestion on Strander Boulevard. • Provide circulation improvements within the superblock and travel path flexibility for traffic associated with the commercial and office developments within or adjacent to the superblock. • Improve access of emergency vehicles to commercial and office developments within or adjacent to the superblock.. It will include a storm drainage system, water line, street lighting, sidewalks and signals at each intersection. Total project cost is estimated at $3.1 million. DESCRIPTION OF ALTERNATIVES The new roadway will have a 61- foot.right -of- way -for roadway, sidewalk, and landscaping, plus utility and fill slope easements. Its general alignment (Figure 2) is currently occupied on the north by-the Parkway Square Shopping Center service drive /fire lane /1"andscape buffer on the west third and by Tukwila 'Pond and its associated wetlands on the east two - thirds. The western two - thirds of the south side of the alignment is the trick loading /customer pickup area for the Bon Warehouse, the warehouse itself and two railway spur lines. The eastern third of the south side is occupied by the railroad main lead track, a power trench and employee parking for Boeing Computer Service. Four action alternatives were evaluated in the Preliminary Design Report for the project (Entranco Engineers, 1986). A typical roadway section and the four alignments are graphically portrayed in Figures 3 through 15 and described in more detail in Section II of this document. 3 Alternative A is a 48 -foot, 4 -lane roadway with a 6 -foot sidewalk on the south side. The Parkway Square service drive will be relocated closer to the building to provide room for the roadway. East of Parkway Square, the alignment shifts 43 feet to the north to minimize impacts to the. Bon Warehouse, railroad tracks and power trench. Alternative B is a 40 -foot, 3 -lane roadway (one lane in each direction and a center left -turn lane). All other features are the same as Alternative A, except that its narrower width means it shifts 36 feet to the north. Alternative C is a 48 -foot, 4 -lane roadway with a 6 -foot sidewalk on the south side. Its west end begins further north than Alternatives A and B, thus eliminating the service drive. The shift northward is then only 27.5 feet, hut cuts through the Tukwila Pond area in the same place as Alternatives A and B. Alternative D is a 48 -foot, 4 -lane roadway with 6 -foot sidewalks on both sides. It is a straight alignment centered about the property lines, beginning at the same point as Alternatives A and B on the west end, hut not jogging north into the pond area. Alternative E is the no- action alternative. MAJOR ENVIRONMENTAL IMPACTS AND MITIGATING MEASURES All four action alternatives will achieve the necessary improvements in traffic circulation, safety and property access. Impacts to the natural environment are relatively the same for all action alternatives, except as related to the Tukwila Pond and wetlands with its associated plant and animal life. Impacts to the built environment are similar for all alternatives with the exception of truck parking. Impacts for all five alternatives are summarized in Table 1. SPECIAL ISSUES OF CONCERN This draft environmental impact statement describes existing conditions and project alternatives. It evaluates environmental impacts for the following environmental elements: 4 TABLE 1 Impact Summary of. South 168th. Street Project ELEMENT OF ENVIRONMENT ATERNATIVE A ALTERNATIVE 8 ALTERNATIVE C ALTERNATIVE D NO- ACTION ALTERNATIVE E EARTH • Filling Pond • Erosion • Stability • 0.5 acre of pond would be filled. ▪ • 0.22 acres of pond • Smaller pond completely filled. - would be filled; • Smaller pond retained. • Some impact during construction; could be controlled. • Slight settlement of electric vault and Bon Warehouse predicted • No Impact • No Impact • No Impact • No Impact AIR QUALITY • Short-term • Long -term • Temporary reduction in quality due to construction activities: dust, equipment, emissions, reduced traffic flow. • Degraded along new street corridor from addition of traffic; impacts on surrounding streets lessened as traffic diverted to new street. • No Impact • Degraded quality in surrounding street areas. WATER • Short-term • Long -term • Temporary possibility of pollution and increased turbidity during construction activities. • No Impact • Increased impervious area and therefore stormwater runoff. Slight increase in stormwater flows • No Impact to P -17 drainage system. • Some pollutants added to runoff from road surface; diverted away from pond to P -17 system. PLANTS AND ANIMALS • Short-term • • Long -term • • • Noise during construction activity, possible increased sediment in pond. Loss of 2.8 acres of habitat and food sources (open water, wetlands, trees and shrubs) for organisms, loss of natural buffer between pond and commercial areas. Added noise, light glare, human activity and refuse. Some species of animals especially waterfowl, may leave, causing competition elsewhere. - • No Impact • Smaller area of pond• No Impact impacted. • Small pond and nesting habitat in southeast corner retained. NOISE • Short-term -• Long -term • Operation of equipment during construction may increase noise 10-20 dBA. • Impacts to area from 6,500 to 11,000 vehicles on new road (redistributed from roads in area). • New road may facilitate new development, resulting in increased noise. • No Impact • No Impact • No Impact LAND USE • Zoning and Land Use Policy • Right -Of -Way Acquisition Total Property 120,000 sq.ft. • Loss of valued wetland habitat. - • Loss would be some- • No Impact what less. 114,000 sq.ft. Percent of Total Tukwila Pond 62% 65% Bon Warehouse 23% 19% Parkway Square 12% 13% TCW 3% 3% 3% 16% • Easements • Revisions required for Puget Sound Power and Light Power Trench and Union Pacific Railroad. • Setbacks • Parkway Square and TCW properties would become approved non -conforming land uses. • The Bon Warehouse would become ap- proved non -con- forming land uses. • Would need to be moved into TCW park- ing lot. • Parkway loses 3 sp's. and service drive. • Shorten 23 Bon truck spaces. • TCW loses 6 spaces. 118,000 sq.ft. 120,000 sq.ft . 62% 18% 17% 34% 34% 16% • Railroad Relocation • Parking • No Impact • TCW, Bon, Parkway spaces respectively. • Shorten 7 Bon truck spaces. • No Impact • No Impact would lose 0,12,14 • Parkway loses 14sp's. • and service drive. • Shorten 15 Bon truck spaces. truck spaces. • Shorten 5 Bon • No Impact • No Impact • No Impact • No Impact • No Impact TRANSPORTATION • Short-term • Traffic • Railroad • During construction, traffic patterns may be slowed by construction equipment. • Improved LOS at Southcenter Parkway /Strander Boulevard. Decreased LOS at Andover Park West/Strander Boulevard • Improved circulation and traffic patterns in "Superblock ", travel path choices and emergency vehicle response. • 23% reduction in traffic on Strander Boulevard. Reduced accidents. • No Impact • No Impact • No Impact • Would be relocated. • Limit hours for train movement. • No Impact • Poorer LOS and circulation in "Super- block." • No Impact • No Impact AESTHETICS - • Negative impact of natural vegetation removal and partial filling .. • No Impact encroachment" of Tukwila Pond during construction. UTILITIES • Relocation and adjustment of all utilities. - • No Impact • Relocate 600 feet of power trench. - • Relocateentirepower • No Impact trench. • Increased storm drainage from impervious surface runoff. ► • No Impact • Added water main, fire hydrants and street lights • No Impact. 7 3-7:168.M4 Earth Air Water Plants and Animals Noise Land Use Transportation Aesthetics Utilities These elements were selected for analysis based on written responses obtained from distribution of a determination of significance and scoping notice (EPIC- 294 -75) issued by the City of Tukwila in November 1985. Scoping comments are shown in Appendix A. The reader is directed to two particular sections which discuss impacts to: (1) wildlife and their habitat located on the Tukwila Pond property (see page 4f1, the Plants and Animals section of the EIS, and Appendix B), and (2) adjacent developed properties (see page 56 in the Land Use Section). For the proposed road project, there are environmental tradeoffs to these uses. 8 SECTION II ALTERNATIVES INCLUDING THE PROPOSED ACTION II ALTERNATIVES INCLUDING,THE PROPOSED ACTION PURPOSE AND NEED FOR ACTION The City of Tukwila is proposing to add a new east -west link arterial to the existing roadway network. The new arterial, South 168th Street, will join Southcenter Parkway and Andover Park West in the central business district (CBD) of Tukwila, between existing commercial property to the south,' and Tukwila Pond and additional commercial property to the north. At present there are no east -west cross streets in the superblock; a planned extension of Minkler Boulevard is to the,south of and parallels the proposed South 168th Street (a final environmental impact statement was completed for this project in 1986). The Tukwila City Council has adopted a six year Transportation Improvement Program for the time period 1985 to 1990 which includes a prioritized list of proposed roadway improvements. Minkler Boulevard is listed as priority number 1 on that list, and South 168th Street as priority number 9. The total project cost of South 168th Street is estimated to be approximately $3.1 million. The fundamental needs that will be met by constructing South 168th Street include: • Elimination of circuitous travel movements currently experienced in the area of the "Superblock ". • A reduction in the traffic volumes on Strander Boulevard. • A reduction in excess travel time in the area. • Alternative access to commercial properties in the area. • Improvement to emergency vehicle response times. • Provision of viable travel path options for avoidance of potential congested areas. 9 Traffic prohlems which currently exist in the "Superblock" area include lengthy queues occurring during the noon and p.m. peak hours at the turn lanes approaching the intersections of Strander Boulevard /Andover Park West, Strander Boulevard /Southcenter Parkway and South 180th Street /Southcenter Parkway. PROJECT SITE AND ENVIRONMENTAL CONSIDERATIONS The proposed South 168th Street alignment intersects an area of hoth heavy commercial use and wildlife habitat (Figure 2). Parkway Square Shopping Center, fronting Southcenter Parkway, runs 700 feet along the north side of the proposed South 168th alignment. A 30 -foot easement for a future roadway occupies the south boundary of the Parkway Square property and is currently used as a service driveway /fire lane along the hack of the stores, and as a landscape huffer. An undeveloped property known as "Tukwila Pond" occupies the remainder of the north side of the South 168th alignment, abutting Parkway Square on the west and Andover Park West to the east. The Tukwila Pond site comprises a shallow pond (19.5 acres) and associated wetlands. The U.S. Army Corps of Engineers has determined the pond to be a wetland. Several developments have heen proposed for the property, the most recent being a planned commercial development. The City has recently entered into discussions with another developer concerning the Tukwila Pond property. At the time of publishing this document, no development permit application had been submitted. The western 1,350 feet on the south side of the proposed roadway alignment is occupied by the Ron Marche Warehouse. The warehouse acts as a regional distribution center for Bon stores. A Bon retail warehouse furniture store is also housed in a small portion of the building. The western portion of the Bon site is an employee and customer parking lot. On the north side of the huilding, a paved driveway and truck dock doors for customer pickup from the furniture store occupy the western 120 feet. Immediately to the east, the truck loading area for the regional distribution center is made up. of 23 dock doors, occupying 280 feet of huilding frontage. There is approximately 100 feet of paved apron space between the dock doors and the northern property line, which is used as . parking area and for maneuvering tractor trailers in and out of the docking facilities. The eastern portion of the Bon building is 60 feet from the property line and adjoins two railway spur lines used for bringing 10 merchandise to the warehouse. The. rail lines form a single main lead track at the eastern property line. There is a driveway used for truck access from the south and east located parallel and to the north of the railroad tracks. The balance of the commercial property on the south side of the proposed roadway alignment is owned by TCW Realty Advisors and is currently used by Boeing Computer Services. The railroad main lead track and Puget Sound Power and Light's (PSPL) utility trench occupy the northern 40 feet of this property. The utility trench runs from Andover Park West, across the northern part of the Bon and TCW properties, to Southcenter Parkway. The power cables cross under Southcenter Parkway in conduit and enter a PSPL substation. Employee parking occupies that portion of the TCW site immediately south of the power trench and railroad lines. There are a number of environmental constraints and concerns related to constructing and operating the proposed arterial, including right -of -way alignment adjacent to neighboring commercial properties, power utilities, railroad facilities and the wetland habitat on the south perimeter of Tukwila Pond. Owners of these properties (shown in Figure 2) have raised the following issues that may he mitigated in whole or in part by the project design. Parkway Square Shopping Center • Potential loss of the service driveway on the south side of the property. Potential limitation of tenant and customer access to the south side of the property due to setback requirements. • Potential design problems for the roadway as well as building foundation and access problems due to the difference in elevation between the building and the proposed street. Potential traffic access and associated safety problems when entering the shopping center from Southcenter Parkway. • Potential impaired views of commercial signs. • Potential economic impact of the roadway development on the property owner, and potential economic impact to the shopping center during construction. 11 The Bon Warehouse and Distribution Facility • Potential interference with receiving dock operations on the north side of the building. • Potential economic impact to property owner if receiving dock operations have to be shifted from north side of building to accommodate proposed roadway. • Potential blockage of the arterial during docking operations and associated traffic safety problems. TCW Realty Advisors • Potential impacts from relocation of railroad tracks onto their property. • Possible costs to property owners for roadway construction and right -of -way acquisition. • Possible economic impact of costs to property owners for railroad and utility relocation. Tukwila Pond Property • Possibility of unsuitable soil conditions for supporting the new road. • Impacts to the wetland /pond habitats and the organisms they support. • Potential economic impact to property owner through right -of -way take of developable land. ALTERNATIVES Similar Features for All Alternatives South 168th Street will be an approximately 2,000 -foot long arterial which will join Southcenter Parkway and Andover Park West at T- intersections. Traffic signals at each intersection and street lighting along the length of the new roadway are included. A 12 -inch water main along the roadway has been proposed by the City of Tukwila Comprehensive 12 Water Plan. Catch basins and a storm drain system are recommended along the length of the roadway, joining to existing systems at Southcenter Parkway and Andover Park West. A minimum'of 61 feet of right -of -way will be required for all alternatives. There will also he a 10 -foot utility easement along the north side of the street for fire hydrants and street lights placed behind the sidewalk. Typical roadway sections (Figure 3) show these features. In addition, easements for slope cut and fill will be needed in some places. These slope easements are important in evaluating impacts to Tukwila Pond and are shown for alternatives in Figures 4, 7, 10 and 13. Four alternative roadway alignments (Alternatives A, R, C and D) have been evaluated for the South 168th Street project. Figures 4 through 15 show an aerial and two plan views of each alignment, beginning on page 16. All alternatives will achieve the necessary improvements in traffic circulation, safety, and property access discussed under Purpose and Need for Action. In addition, the no- action alternative (E) was examined. Alternatives A, B and C (Figures 4 through 12) are similar in general alignment, shifting to the northeast at the east end of Parkway Square (into the Tukwila Pond property). These alternatives all encroach on the south edge of Tukwila Pond habitat to avoid the Bon receiving dock. Alternative 0 (Figures 13 through 15) maintains a straight alignment, and although it encroaches on pond habitat, it affects it the least of the four action alternatives. Alternatives A, C and D are four lanes; Alternative B is three lanes. Alternatives A and B maintain a service drive to the south of Parkway Square Shopping Center; Alternatives C and 0 do not. Alternative A Alternative A is proposed to be a 48 -foot, four lane roadway with a 6 -foot sidewalk on the south side of the street (Figures 4 through 6). The north edge of the roadway will he 34 feet south of the Parkway Square building and allows for a 20 -foot service drive along the south side of the building. The service drive would be 5 feet closer to the building than at present, with only 5 feet clearance from the building. Access to the drive will he from South 168th, rather than from the east parking lot, as is presently the case. The drive will he separated from South 168th by a 3- to 4 -foot high retaining wall and a 5 -foot landscape buffer between the wall and the curb. East of the Parkway Square building, the roadway alignment will shift 43 feet to the north, and continue east to Andover Park West. The hack edge of the sidewalk for this alignment will be 4.5 feet south of the TCW Realty Advisors property line and adjacent to the truck apron. 13 Alternative B Alternative B (Figures 7 through 9) is proposed to be a 40 -foot, three lane roadway with a 6 -foot sidewalk on the south side of the street. This alternative will provide for one lane in each direction and a center left turn lane. The 40 -foot width is recommended to accommodate the large amount of truck traffic in the area. The alignment for this alternative closely resembles that of Alternative A, except that the alignment shifts only 36 feet to the north at the east side of Parkway Square instead of the 43 feet required for Alternative A. Alternative C Alternative C (Figures 10 through 12) is proposed to he a 48 -foot 4 -lane roadway with a 6 -foot sidewalk on the south side of the street. The north edge of the roadway will be 18 feet south of the Parkway Square building and will not provide for a service driveway. Ramps will be constructed from the street level to a sidewalk adjacent to the building and will provide access to the service doors on the south side. The street will be approximately 4 to 5 feet lower than the building. The roadway alignment will shift only 27.5 feet north from the east end of the building and continue to Andover Park West. Alternative D Alternative D (Figures 13 through 15) is proposed to be a 48 -foot 4 -lane roadway with 6 -foot sidewalks on both sides of the street. The north edge of the roadway will be 6.5 feet south of the Parkway Square building and, like Alternative C, will not provide for a service driveway. The alignment will be centered about the current property lines and will be a straight alignment between Southcenter Parkway and Andover Park West. Alternative E Alternative E is the no- action alternative. 14 434 BOEING COMPUTER SERVICE 1177-7i • -71 LEGEND: 111■1, .11■1• ./1111111, ■••••• EXISTING PROPERTY LINE CORRIDOR BOUNDARY ENTRANCO ENGINEERS. INC. 4AP'7',,IttiETSP*P CITY OF TUKWILA, WASHINGTON Figure 2 SOUTH 168TH STREET Project Area NORTH SCALE: 1" = no. 5 61' ROADWAY 24' + 24' 2° 2 °/ 6' aiL 0.5' al ASPHALT CONCRETE SIDEWALK CRUSHED SURFACING CRUSHED SURFACING GEOTEXTILE CURB & GUTTER FILL BUILDING POND EXISTING GROUND 20' SERVICE DRIVE ASPHALT CONCRETE CRUSHED SURFACING RETAINING WALL • ROADWAY SECTION NOT TO SCALE , 61' 7 7 r• 24' c. ROADWAY 24' EXISTING GROUND CRUSHED SURFACING ASPHALT CONCRETE Fl LL ROADWAY SECTION NOT TO SCALE SIDEWALK CRUSHED SURFACING RAILROAD 1-- __A EXISTING POWER TRENCH ANDOVER PARK WEST TCW BOEING COMPUTER SERVICES TUKWILA POND PARKWAY SOUTHCENTER PARKWAY KEY PLAN N.T.S. J ENTRANCO ENGINEERS. INC. CITY OF TUKWILA. WASHINGTON SOUTH 168TH STREET Typical Roadway Sections Figure 3 15 ENTRANCO ENGINEERS, INC. CITY Of TUKWILA, WASHINGTON SOUTH 168TH STREET NORTH SCALE: 1" = 220 Figure 4 Alternative A Alignment 16 Q cc a.n w•r 50u■°f •wren w °.,..r. N. . • - 27 cA SOUTH 8168TH STREET N 88 °04' 38" W_ 0313 ESMw OI . II ' IY Q 0. V� W O W H Z 0 tal II = r I-- •dt t-p III ■ EM1 6 Cwem E i0, vEy, rr°E 115 °..::N_G W aY e• I � • rUEE 'aft H w O O o • Q F W z J J,it €Sur evf 0 1.0.0••Gr uwLOeD wr, e°E• I I..„ EVE 8 i? uCE, . -. • S 3°, E5Y, \\ I so (0 aw,ED•ufc .r iI 0I d BON MARCHE WAREHOUSE e ENTRANCO ENGINEERS, INC. NORTH (- w W Z (n 0+00 -TH 8080.6 Id UTILITY EASEMENT in w m amp ■■•■■■ N N r 4) W z J Z U (- Q F 1-. w - MEYEwM: - I 8, ,- f.' Cw•�w E,' "U_ x xC.aw •.wS X x Sn - x X = • — .za - ,-413 _ / .0 - x 1 S -r_ }[ _ • E. s 3 I -COwCh i TRUCK APRON 90,1 ve °C.E we °E wOUSE SCALE; 1' = 40' CITY OF TUKWILA, WASHINGTON SOUTH. 168TH STREET Alternative A Plan Sta. 51-00 to Sta. 15+00 Figure 5 17 0 00 T Q Ln F iA z 0 4 Q ••••• i - - r10 UTILITY EASEMENT B CNAAN LAM A 2" SD RUILO1MG w ,•AV PARKING • �{wnrvwvww,�imw+v in 0 N O C I oL f�. 0) T_ ._ 1- -4- 4 —{— SPRINKLE R vitt E •RR SW r[N PA•• 0EO n.E• L 1 *000 BUILDING cot ti W PAVED PARK .NG EE D .. MATCH LINE ST in a N N a SD I2EE SD 12.. SD ".— SD 12•. SG.'"s 10' UTILITY EASEMENT r Pr7 12!! 0 -THIS SHEET EC Aug • II •UE* 12 W G •R w.n .:;a. rau»r,m.�m> ttrzrma¢�awce rw Fa�Ea»xMOeowaysaz «» zwaMeN. wow �.wmw.�.,ewr.,e.saa««.aewo> 1I ENTRANCO ENGINEERS, INC. NORTH SCALE f= 40' PL•NTER •L SNr(D AREA vEO RAR,('G 00E■NG CO••urE• SERVICES CITY OF TU,KWILA, WASHINGTON } 4 16; SOUTH 168TH STREET E 'lfi •B:rY. �v• I■�. 3i MOr E Zy MON IN C•SE ii ANDO Alternative A Plan Sta. 15 +00 to Sta. 25 +02 J Figure 6 18 ,*4 - • -; r., ;tr, jy; Som , STRANDER BOULEVARD 40' z' ..1•” " ."" POWER TRENCH 4*, TC RECEIVING DOCK ; BON WAREHOUSE BOEING COMPUTER SERVICE tWrZ/f, 11 ENTRANCO ENGINEERS. INC. NORTH SCALE: 1" = 220' CITY OF TUKWILA, WASHINGTON SOUTH 168TH STREET LEGEND: .1■111•■ ■••••■•• /MEW 1■2•••■ EXISTING PROPERTY LINE PROPOSED CURB S GUTTER PROPOSED TOE OF SLOPE Alternative B Alignment Figure 7 19 f 0s.. WAY SOu6Bf L s1..00 40(6 Cr.•,1. 111.. � !L 166d. 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SOu•RE N 6 -w N 7` UTIL ESEIT •5••■■ 0Pl•f Ii VI S 1 coNIC I E— w w fn e � NIv _ _s.uEY -i- ISOUTH ff./ 168TH STREET L + 88 °04'38 "W w0 we - -0. IOM N/CUERA 6 C..•.N LIN• l• v NS «» . « c ...»„ «00..14...17,.►. 81 GS 11° CON: PAO C ON, pOt. • =•.E a•a• ENE. 50\ L•N,fD ANE• r, CONIC NM '0Y 0/6 oft. r \ (LEG COND.T — " i J • 80 /(0 •PE• 0 e ENTRANCO ENGINEERS, INC. 4 NORTH 1- w N 2 F•• 0 0 •vt' °�N.•N4 •NTEP it 1 SP*INYLFR LINE 0 at. ANrEO AREA J 4 4 f T I Y • II • • = -0 • Y MEE =ES li .• wiNRwlt sAlrlRawwL x:.. -•a >ac:. "a+di1� UiM�a Y 'C I'S� ="Z _•5°N _ . Ra f _ . HMI 1 - Y - 7L20 •G0E SL GPE SS ESN, SOUTH I68TH 13 STREET N 88°04'38• W 14 1111W- 'New, CNAIN LIMA • 50 —0 •Et. ESN• 0 '2 • 3 d d _l I ;-iON _ E • io+ ...PC.' •• ENOUSI DNT. w Z 1 i 4 •T- ± SCALE r= 40'' CITY OF TUKWILA, WASHINGTON SOUTH 168TH STREET Alternative D Plan Sta. 5 +00 to Sta. 15 +00 Figure 14 26 0 0 H N w Z J 0 4 i 16 N 17 O C 1 8 CE `CIM 5D 2 fONC 2-CONC 1 1 1 1 I ' <1Aw eN::J • r„ SO SOUTH 168T1-1 STREET N88 °04.38 °W f�1 p CS I I I 1 0U•t DING .Pay( i •0r.0t. 18 •t S ER q 19 • • OI•N•ED 6000 l°000 8Wl D.G \y 4011 \6j • Nod( D 040.•04 w w 2 N 2 F o 0 0 0 N 4 w Z J 2 0 1- Q f 00 -THIS SHEET e ENTRANCO ENGINEERS, INC. 4' NORTH 0 . z 4 1 21 22 SOUTH 168TH STREET N88°04' 38' W f�1 23 -1 — -- - -- - 24� YOM IN ' six 'ro iSW" t9 .r''$iG ,t--IMMINENT - r°EANTE. —� 66 � l 00vf D 040..04 II 00E SENV.CES 0140 =EO 0000 1 II I II r SCALE 1•= 40' 11 CITY OF TUKWILA, WASHINGTON r�I 11 • II 1 It ! A .4 JC $ GN w 3 ° CC }n K 8 0 4 11 I III 1 SOUTH 168TH STREET Alternative D Plan Sta. 15 +00 to Sta. 25 +02 Figure 15 27 SECTION III AFFECTED ENVIRONMENT, SIGNIFICANT IMPACTS, AND MITIGATION MEASURES III AFFECTED ENVIRONMENT, SIGNIFICANT IMPACTS, AND MITIGATION MEASURES The following discussion addresses existing conditions, environmental impacts, mitigating measures and unavoidable adverse impacts for each environmental element. For clarity, "project .site" impacts refer to the area to he directly affected by the roadway. The project site is defined as an area about 2,000 feet long by approximately 90 feet wide. The "project site" is distinguished from the "project area" (Figure 2), which also represents adjacent land and water areas. NATURAL ENVIRONMENT EARTH Existing Conditions The proposed project is located in the Green River floodplain and is generally flat. Elevations vary approximately 10 feet over the project site with the highest elevations occurring to the west adjacent to the Parkway Square building., and the lowest areas occurring along the shoreline of Tukwila Pond. Surface soils on the project site are fill material, including sand and gravel, along the western half of the property (Figure 16). The naturally occurring soils underlying the fill and on the surface of the eastern half of the alignment are alluvial sands and silts, including two thick layers (40 to 50 feet) of compressible silt. The present soil conditions on the project site are stable and generally not erosion prone due to existing vegetation. At present, the proposed roadway alignment is made up of approximately 10 to 20 percent impervious surface, which reduces the potential for rainfall to soak into the ground and creates surface runoff from the site. 29 Environmental Impacts During construction of the new roadway, approximately 8,000 cubic yards of existing surface soils would he removed off site and replaced with select fill. Fill will be placed on the Tukwila Pond portion of the site to a maximum final depth of 11 feet (after settlement) with side slopes in the proportion of 2:1 horizontal to vertical in order to raise the existing ground level to the elevation of the roadway. Grading of other portions of the site will occur to match roadway elevations. Under Alternatives A, B, and C, approximately 17,000 square feet of the main area of Tukwila Pond, and 3,600 square feet of the eastern pond, will be filled. The fill will displace approximately 0.50 acres of pond, with a portion of the fill being placed below the water level. Alternative D will require 9,500 square feet of the main pond and 35 square feet of the eastern pond to be filled, for a total loss of 0.22 acres of pond. Removal of vegetation and topsoil for construction of the roadway will temporarily increase erosion potential. During construction, runoff from exposed soils may contain a significant sediment load. After construction, over 90 percent of the project site surface would be impervious. Runoff would not cause on -site erosion due to containment in a drainage system which would tie into adjacent street drainage and not discharge to Tukwila Pond. The proposed roadway embankment is expected to settle more than 2 feet over the course of a year, with 60 to 70 percent of the settlement occurring within three months of fill placement. Existing utilities such as the concrete electric vault, and structures such as the Bon Warehouse, may also settle; approximately 3 inches of settlement is anticipated for the vault and 1.5 inches or less for the Bon Warehouse. Alternative E, no action, would continue existing earth conditions; no impacts would occur. Mitigating Measures The amount of wetland fill /encroachment could be minimized by the following measures: • Selection of Alternative 0, realizing the coincident land use and utilities impacts, and higher project costs. 30 40 20 -60 a a W O 0 W 1` W o N a Y a WEST EDGE BON WHSE. W N) t9 } 0 Q W 1-- Y N CC W d W O 0 W VERY LOOSE TO MEDIUM DENSE, GRAVELLY VERY SILTY w SAND TO SANDY GRAVEL (FILL) EAST EDGE -100 -- 5+00 4 LOOSE TO MEDIUM DENSE, SLIGHTLY SILTY TO SILTY, FINE SAND 9 9 41 N = 0 W 1- 0 4 PROPOSED ROADWAY GRADE 0 Z O a Q J Y 3 1- 1- D: u) W W 3 O 0 a Z as EXISTING GROUND LINE LOOSE, SILTY, FINE SAND AND VERY SOFT SANDY SILT SOFT TO MEDIUM STIFF SILT WITH ORGANICS 1 — MEDIUM DENSE TO DENSE, FINE TO MEDIUM SAND LOOSE FINE TO MEDIUM SAND WITH SILT INTERBEDS SOFT TO MEDIUM STIFF, CLAYEY SILT FINE SAND 9_.__�- MEDIUM DENSE TO DENSE, FINE TO MEDIUM SAND • • 10 +00 NOTES: I. STRATUM LINES ARE BASED UPON INTERPOLATION BETWEEN EXPLORATIONS AND MAY NOT REPRESENT ACTUAL SUBSURFACE CONDITIONS. 2.2 DESIGNATES EXISTING GROUND WATER LEVEL AT TIME OF DRILLING. 15+00 STATIONING ALONG S.I68TH STREET ALIGNMENT 20 +00 9 25 +00 HART - CROWSER & associates inc., FEB. 1886 ENTRANCO ENGINEERS, INC. CITY OF TUKWILA, WASHINGTON SOUTH 168TH STREET Soils Profile Figure 16 31 • Use of a retaining wall on the north side of the roadway in Iieu of a fill slope. This would also increase project costs. Elimination of about 6 feet of right -of -way from the north side of the road for future sidewalk installation. This would conflict with the City of Tukwila sidewalk policy. A compact select fill will be placed under the entire roadway with pavement overlaid. A minimum of 2 feet of fill, 5 inches of coarse crushed rock, 2 inches of finer crushed rock and 4 inches of asphalt concrete could be used, which conforms to pavement design procedures specified by the Washington State Department of Transportation. Erosion control during construction may include dry weather construction and temporary mulching and seeding of cleared and filled areas. An in -pond geotextile fabric harrier or other appropriate device will be installed to minimize pond turbidity during clearing and filling. This would also serve as a visible limit for placement of fill. Permanent landscaping of the roadway boundaries following construction would reduce erosion potential. Unavoidable Adverse Impacts Some erosion and loss of sediment from the site could occur during vegetation clearing, laying of geotextile fabric, placement of fill, and roadway construction. There may be some slight settling of existing structures such as the electrical vault and the Bon Warehouse. Under Alternatives A, B, and C, approximately half an acre of Tukwila Pond will be filled. Alternative D provides for filling less than a quarter acre of the pond. AIR Existing Conditions Total suspended particulates (TSP) are released by automobile and truck traffic, industrial output, and from other sources and are composed largely of particles of dust, soot, organic matter and mixtures of sulphur, 33 nitrogen and metals. Carbon monoxide is produced by motor vehicles and is generally used as an indicator of the extent of the air quality impact from traffic. During construction of the road, the generation of dust is a typical impact. Although the Washington State Department of Ecology and the Puget Sound Air Pollution Control Agency (PSAPCA) maintain a network of instrumented air quality monitoring stations, there are no agency- operated monitoring stations in the project vicinity. Nonetheless, some general statements can he made based on the regional data. Total suspended particulates are measured by the PSAPCA at three stations in the area: 200 South 2nd Street (Renton), 12026 - 46nd Avenue South (Duwamish Valley), and 2.2916 - 86th Avenue South (Kent). As of September 1985, the site is considered to be within the range of 40 to 50 ug /m3 for the annual geometric mean of TSP, which is below both primary and secondary federal standards and Washington State standards. In the project area, there are no large industrial sources of air pollutants. Although sulfur oxides and nitrogen dioxide are emitted by home heating and motor vehicles, concentrations of these pollutants are generally not high except near industrial facilities. These pollutants have not been measured in the project vicinity, but it is unlikely that concentrations are very high here. The Seattle- Everett - Tacoma region is officially designated as a "non- attainment" region for ozone standards. But because monitoring data from the last several years indicate that ozone levels have not exceeded ambient standards, the PSAPCA has requested that the area be reclassified as attaining the standards. The Environmental Protection Agency has agreed and plans to publish its proposed approval of the redesignation in the Federal Register. Unlike ozone, carbon monoxide is a pollutant whose impact is usually very localized. The highest ambient concentrations of carbon monoxide occur near congested roadways and intersections during periods of low temperatures, light winds and stable atmospheric conditions. Because the impact occurs so close to the source, it is not possible to extrapolate carbon monoxide concentrations from regional data. 34 In general, however,'.: carbon monoxide concentrations have been decreasing due to more stringent vehicle emission standards for newer cars and the gradual replacement of older, more polluting vehicles. Lead concentrations have also been decreasing as leaded gasoline is being eliminated. Environmental Impacts Quantitative air quality monitoring and predictions were not performed for this project. In general, quantitative assessment is recommended by PSAPCA when projected traffic volumes exceed an average of 20,000 vehicles per day. Worst case traffic projects for this proposed road are about half that (11,000). For all action alternatives (A, R, C and D), the following impact discussion is similar. Construction. From an air quality perspective, the largest impact from construction of all South 168th Street action alternatives would he dust. Excavation and grading work break up the soil and generate dust, which is carried by winds out of the construction area. Other sources of dust include soil blowing from uncovered dump trucks and soil carried out of the construction area by vehicle frames and tires; this soil is deposited on adjacent streets and often hecomes airborne. Construction would require the use of heavy -duty vehicles such as bulldozers, road graders and heavy trucks, and smaller equipment such as generators and compressors. These engines would emit air pollutants which would contribute slightly to the degradation of local air quality. Sometimes construction equipment and material hauling can affect traffic flow in a project area. If construction traffic were to significantly reduce travel speeds in the area, emissions from general traffic would increase. Open burning of slash and other material, if permitted, would produce smoke and other contaminants. Street paving with hot asphalt would release hydrocarbons and associated odors to the air. Long -term. Air quality in the immediate vicinity of all alternative alignments will be slightly degraded by the addition of through traffic. Carbon monoxide, nitrogen oxide, hydrocarbons and other traffic - related air pollutant concentrations will increase slightly along the proposed street. 35 From an areawide perspective, South 168th Street will divert traffic from existing roads and therefore tend to reduce air quality impacts in those areas initially. However, additional roadway facilities increase the total transportation system capacity and therefore increase total potential air pollution loading. Alternative E, no action, would result in no project site impacts; however, long -term project area impacts would be similar to other action alternatives. Mitigating Measures Construction. Emissions from construction equipment and trucks can be reduced by using relatively new, well - maintained equipment. Avoiding prolonged periods of vehicle idling and selecting electrical rather than engine - powered equipment would also reduce emissions. Dust produced by construction can he reduced by using a number of techniques. Areas of exposed soils such as storage yards and construction roadways can be sprayed with water, oils or chemical dust supressants. Areas which might he exposed for prolonged periods can he paved, planted with a vegetation groundcover or covered with gravel. Soils carried out of the construction area by exiting trucks can be minimized by wheel washing and covering dusty truck loads. Finally, that soil which does escape the construction area on existing vehicles can be reduced with a periodic street - cleaning effort. Long -term. Operational air quality impacts are mitigated by reducing the emission rate per vehicle. To date, the Federal Motor Vehicle Emission Control Program has been very effective in reducing vehicle emission rates, but this success is expected to continue for only about another five years unless emission standards continue to be tightened. The State of Washington may wish to consider adopting more stringent emissions regulations in the near future since considerable lead time is required for implementation. The authority to operate the mandatory vehicle inspection and maintenance program which is being used to reduce the emission rates of local vehicles is scheduled to expire in 1990. The continuation of this program would no doubt continue to reduce emissions from local vehicles regardless of the federal or state emission standards. 36 Unavoidable Adverse Impacts A slight increase in air pollutants along the direct roadway alignment would occur with all action alternatives. WATER Existing Conditions Surface Water. The proposed project site lies within the Green River drainage basin and within the 100 year flood plain. Surface water bodies along the proposed roadway alignment include the adjacent Tukwila Pond, a 19.5 -acre shallow pond ranging in depth seasonally from 3 to 6 feet, surrounded by wetlands, and a small, seasonal, crescent - shaped pond (about 0.25 acre) on the southeast corner of the Pond property (Figure 2). The source of surface water to Tukwila Pond is from adjacent paved properties. Most water leaves the pond by evaporation or plant transpiration. There is a 48 -inch storm drain outfall along the eastern boundary of the Tukwila Pond property, which flows north and eventually into the Green River. The proposed roadway is immediately north of the P -17 drainage sub -basin (Figure 17). Surface water runoff from this sub -basin is pumped into the Green River. In the mid- 1960's, the P -17 drainage system was planned in the area by the U.S. Department of Agriculture, Soil Conservation Service as part of the overall plan to provide flood protection in the Green River Valley. Recent revisions to the regional system include the construction of an overflow line to the P -17 drainage channel from Tukwila Pond, constructed in 1985. This line, equipped with a flapgate, runs along Andover Park West, southeast of the site, and prevents backflow from the Green River during high water conditions. Groundwater. The water table in the area of the proposed South 168th alignment is close to the surface (Figure 16). There is most likely little groundwater recharge on the project site due to existing impervious surfaces and relatively impermeable soils. 37 :TUK WILA &CITY 'LIMITS y tea! \j I • •� • i1 • • • 1111111111 S.188TH a E nEC- n LOMOACAIS M P-17 PUMP STATION ' AND STORAGE POND •or. IT I1 . ENTRANCO ENGINEERS, INC. et% NORTH SCALE: 1 "= 1600' LEGEN D: mmillO• DRAIN TO NORTH '=> EXISTING DRAINAGE TO POND /' / /' /n■ DRAINAGE TO P -17 SUB BASIN 1 — 1 P -17 DRAINAGE BASIN ' BOUNDARY CITY OF TUKWILA, WASHINGTON Figure 17 PROJECT SITE AND VICINITY DRAINAGE 38 Environmental Impacts Surface Water. The construction of action Alternatives A, B, C or D will increase the amount of impermeable paved surface area on the project site by about 80 to 90 percent. This will result in additional surface water runoff volume of 3.6 cubic feet per second (cfs) during a storm with a 10 -year reoccurrence interval. Drainage from the proposed roadway will not enter. Tukwila Pond. Stormwater drainage from South 168th Street will be routed via closed drainage systems to the P -17 sub basin (Figure 17), which drains into the Green River. Surface water flow rates from a 10 -year storm will he about 2.1 cfs and 1.5 cfs for the Southcenter Parkway and Andover Park West storm drainage systems, respectively. These systems drain to the P -17 channel system, which is estimated to have a present hydraulic capacity of 254 cfs, which is capahle of handling a 25 -year storm (Alpha Engineers, Inc., 1984). This system was originally designed to accommodate runoff from a 100 -year, 24 -hour storm. Surface water volumes generated by project alternatives will slightly increase flows in the P -17 channel. The new impervious surface created by construction of South 168th Street will collect some additional atmospheric and automobile- generated pollutants which will be washed into the storm system and eventually into the Green River. The volume of runoff generated from the proposed roadway and its load of associated pollutants will slightly increase those from other City of Tukwila storm drains and will proportionately have a slight negative water quality impact to downstream areas (e.g., the Green River). During construction, the fill required for roadway embankments may result in eroded soil entering the two ponds or storm drainage systems to the south and could have adverse water quality impacts on downstream areas due to increases in turbidity and suspended solids. In addition, other byproducts of construction such as oil, hydraulic fluid, and fresh concrete could reach downstream areas (e.g., the Green River). The small pond in the southeast corner of this site would be filled if Alternatives A, B, or C were implemented. Groundwater. No adverse impacts on groundwater are expected for Alternatives A, B, C or D. Any major spill of pollutants from the roadway during construction would soak into the near surface groundwater. If not properly contained, it could reach Tukwila Pond. Alternative E, no action, would continue existing water conditions; no impacts would occur. 39 Mitigating Measures A temporary erosion control plan could be developed and implemented for project construction. This would minimize sediment loss and prevent pollutants from entering adjacent areas. A street cleaning and maintenance program would also help to reduce the potential for water quality impacts from stormwater after construction of South 168th Street. Details of such a program have been discussed under Mitigating Measures in the "Earth" section of this document. Limited P -17 channel capacity could be offset by increasing downstream drainage system capacity, as recommended by Alpha Engineers (1985). Unavoidable Adverse Impacts Construction activities would cause a temporary increase in suspended sediment concentrations in Tukwila Pond, the adjacent smaller pond in the southeast corner of the pond property, and possibly downstream in the P -177, - channel._. 41 area unusual. Lists of plants and wildlife for the project area are included in Appendix B. The variety and productivity of the proposed 168th Street project site is the highest per unit area of the pond property since it encompasses the wetlands, pond edge, tree canopy and the shallow islands in the southwest corner of the pond. Wetlands and Associated Species Under the King County classification, U.S. Fish and Wildlife Service and Army Corps of Engineers definition, wetlands are "Those areas that are inundated or saturated by surface or ground water at a frequency and duration to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions." According to the U.S. Fish and Wildlife's classification of wetland and deep water habitats, the project area contains the following three classes: • Palustrine, emergent: this is the wet grass meadow along the south, bank of the pond, comprised mainly of reed canary grass. • Palustrine, scrub - shrub: this is the riparian horder along the north and south banks. • Palustrine, unconsolidated bottom: this is the open water portion of the area. Wet Meadow (Grass /Sedge Marsh). The area between the south hank of the pond and railroad track is a near monoculture of reed canarygrass. At the pond's edge there are standards of smartweed and heggars tick and occasional clumps of cattail. The higher elevation areas near the railroad tracks have deadly nightshade and blackberry encroaching into the reed canarygrass areas. The small crescent - shaped pond in the southwest corner of the Tukwila Pond property has smartweed, beggars tick and willow along its banks. The wet meadow- grass /sedge marsh comprises 12 percent of the Tukwila Pond property and 70 percent of the wetlands. Because of the high density of vegetation and the lack of vegetative diversity, the south edge of the pond and wetlands up to the railroad fill have limited summer value to waterfowl and marsh birds. 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SCALE: 1" =110' Mammal activity is limited along the south shore of the pond because of the high density of the canarygrass, small size of the site, its proximity to the railroad track and parking area, and isolation from a larger tract of upland habitat. The wet meadow (Figure 18) area does, however, support the following functional wetland values that are important to water quality in the pond: • It is a stormwater retention /detention area that expands during winter storms to encompass the entire south two - thirds of Tukwila Pond property. Its value for retention /detention has recently changed due to the regional drainage system changes described in the Water section. • Sedimentation /pollution control:, the grass wetland and vegetated edge of the pond traps soil particulates, oils and other pollutants from runoff. Reed canarygrass and cattail are effective btofiltering plants. With the exception of one drainage point, all of the water that runs into Tukwila Pond is filtered through grass -lined ditches of flat expanses of grasses. The exception is in the southwest corner, where the water runs in a ditch from parking lots to the pond. Riparian Border. Riparian refers to the wooded or shrub -type habitats that surround or abut, but interact directly with, a pond, wetland or stream. On Tukwila Pond, that border is narrow along the west and north sides of the pond and wider in the southeast and southwest corners, extending up to the railroad track and truck parking apron in the southwest corner (Figure 18). Portions of the south bank have clumps of riparian habitat, with intermittent open spaces between the pond and a second tree /shrub border abutting the railroad track. The southwest corner has a narrow hand of trees extending from the pond along a narrow runoff ditch. Alder is the dominant plant along the runoff ditch in the southwest corner and along the west bank of the pond. The east and southeast corners have older stands of black willow with occasional black cottonwood. This willow stand is lower in surface elevation than other trees on the site; the stand is denser, the trees older, and the understory void of vegetation because of the dense canopy. Snags, crevices and broken limbs supply good small hird habitat. This area also provides the isolation from roads or traffic needed by some wildlife. 45 The riparian border around the small pond in the southeast corner of the site is alder and black cottonwood with an understory of willow shrub and blackherry. The tree /shrub area abutting the railroad track, particularly in the southwest corner, provides a valuable visual screen for the pond and provides islands of taller vegetation in the grass marsh, forming a diversity of hahitats and an "edge effect" wherever there is a distinct change in elevation or type of vegetation. The trees are nesting and loafing areas for a variety of passerine hirds that feed on insects or seeds. The dense tree edge in the southeast corner and along the east bank provides a visual buffer for the pond, shelter from the wind, cover from predators and nesting habitat for a number of species such as towhees, juncos, sparrows and warblers. Eastern cottontail, meadow mice, shrews and voles use the wooded edge that extends from wetland to upland for nesting, feeding and cover. Open Water. There are two water bodies in the project area: the larger 19.5 -acre main pond and the small crescent - shaped pond in the southwest corner. The large pond's depth precludes emergent vegetation throughout much of its area, except in the shallow areas along the banks and in the southwest corner. Along the north bank there are stands of cattail, intermingled with nightshade, and scattered reed canarygrass in the shallower areas. In the southwest corner, in the midst of the dead willow stands, there is a stand of reed canarygrass, nightshade and pondweed in the deeper waters. Cattail grows along the south bank in this area. The small crescent - shaped pond in the southeast corner of the Tukwila Pond property is vegetated around the edge with reed canarygrass and patches of cattail. Aquatic smartweed, pondweed and duckweed grow in the shallower portions. The pond edge creates another "edge effect" with the plant - mudflat -open water interaction. The seasonally exposed mudflat along the southern shoreline provides the required habitat for other wildlife groups. A variety of shorebirds such as solitary sandpipers, dowitchers and plovers wander over the mud and in the shallow water feeding on insects, during the late summer and during fall migration. This area stays flooded during the winter and spring, then slowly becomes exposed in August and September as the migrating shorebirds return from the north. 46 The flooded brush area in the southwest corner of the pond is an unusual habitat that provides excellent cover for a distinct group of species., In the winter, this-area appears to he the preferred cover of the mallard ducks, shovelers and teal on the site. It is also the preferred perch site for juvenile swallow and kingfishers. This habitat is temporary in that it will change in five to ten years as the dead vegetation decays. The open pond appears to be changing, with a persistent vegetative intrusion of pondweeds and other submergent type plant species. This is an indication that the waters are getting shallower. Throughout the seasons, the open pond site hosts a wide variety of wildlife species. The species occurring on the site change dramatically through the year due to changing site conditions and established migration patterns of shorebirds and. ducks. In the fall, the population increases and fluctuates as the migratory birds pass through. During winter, the site is dominated hy permanent residents and ducks that winter in western Washington. Once again, in spring migrating shorebirds, .ducks and songbirds pass through, feeding heavily to support their continued flight north. Also in spring, nesting birds such as ducks, songbirds, pheasant and quail that are established residents, construct nests and raise young. The water's edge is used by mammals for drinking and hunting. Plant eaters, such as mice and rabbits, require water, and predators, such as hawks, exploit this need when hunting the water's edge. The open water is fish habitat for at least two small unidentified species of fish that appear to be food for waterfowl and marsh birds. The edges on two sides of the pond are shallow and support vegetation that is a prime feeding and hiding area for small fish as well as being cover for red - legged frogs and other invertebrates. Herons, mergansers, kingfishers and cormorants have been observed feeding on the fish in the pond. Tree frogs use the area both for breeding and rearing of young. Garter snakes have been seen on the sloped bank adjacent to the crescent - shaped pond in the southeast corner of the site and in the alder thicket areas in the southwest corner. 47 Uplands and Associated Species Upland habitats in the project area are confined to the filled areas surrounding the pond. The fill along the west side is in a state of transition from invader species and upland species such as dock, quackgrass, johnsongrass and clover, to wetland species such as reed canarygrass, softrush, beggars tick and other semi - aquatic forbs, and willow and black cottonweed trees. This area comprises approximately 35 percent of the Tukwila Pond property, but less than 10 percent of the proposed road project site. The low grass /rush stand in the upland area supplies seed and green vegetation to a variety of small passerine birds, pheasants and quail. The riparian zone supplies cover, food and nesting for most of the same species. The tangle of blackberry /nightshade provides protection from predation for nesting and juvenile rearing. Trees are nesting habitat for a variety of small birds as well as perching and hunting stations for small raptors and kingfishers. Trees adjacent to or overhanging the water provide shade and protection for juvenile ducks. Grassy edges provide nesting for mallards. In winter, the uplands are used as a feeding area for ducks and shorebirds that also use the pond for escape and loafing. A variety of seed eaters and grazers, including meadow mice, voles and eastern cottontail rabbit, use the uplands and riparian border. Rabbit use appears to be fairly heavy in the dense thicket in the southwest end of the proposed project site. The area does not appear to be used for dog walking. Trails of the size required for such use were not present and there was no sign of random dog use. This, plus the isolation from predators, makes this a safe habitat for wildlife. Unique Species Review of Washington State Department of Game and U.S. Fish and Wildlife Service documents, contact with personnel in the endangered species programs of both state and federal agencies, and a review of data and reports collected over the years by the Audobon Society indicate that there are no Endangered, Threatened or Sensitive plants or animals on the site. 48 Migration Routes The site is within the Pacific Flyway, and as such is utilized by birds that normally migrate through the western Washington area in spring and fall. The pond is heavily used by both waterfowl and shorebirds. The uplands and riparian border are used by goldfinches, siskins and other small birds. Environmental Impacts Impacts were evaluated for Alternatives A, B and C together, since their impacts on wetlands and pond are identical, and Alternatives D and E. Impacts are divided into direct (loss of habitat and impacts on wildlife), and secondary (noise, water, quality, human disturbance, etc.). These are divided into construction and operational impacts. Direct Impacts Wetland Habitat Elimination. The fill area for Alternatives A, B and C would eliminate approximately 2.8 acres of reed canarygrass marsh and pond, a stand of young alder, mature larger alder and willow trees, and a 1,200 -foot long vine /shrub bramble between the edge of the wet meadow and the railroad track (Figure 18). The drainage ditch and dense alder stand extending east from the southwest corner would also be lost. The shallow mudflat and cattail at the pond edge area in the west end and a portion of one shallow snag- filled island would be eliminated. The mudflat is only exposed during low water periods. Its width and duration of exposure is 49 The proposed fill slope planned at the edge of Tukwila Pond would also eliminate the natural buffer between existing rail and truck traffic patterns and the pond edge. Filling into the pond would increase sediment loads, water turbidity and eliminate organisms living adjacent to the toe of the fill that are intolerant of high sediment levels. Sediment will also blanket the shallow areas, smothering mudflat organisms. As the sediment clears, these impacts would be reduced, then cease once the slopes of the road are stabilized with vegetation. The road for Alternatives A, B, C and D would eliminate all of the large trees, shrubs and the blackberry bramble along the existing railroad and parking lot fill. Although Alternative D would still eliminate about 1.8 acres of wetland and pond, the impacts to wildlife are less. The fill would extend into the small pond, hut not to the extent of alternative A, B or C. It would also miss the small snag islands and part of the alder stand in the southwest corner of the large pond. It would still remove the reed canarygrass meadow, most of the alder tree stand in the southwest corner and the large trees along the railroad track. Wildlife Impacts from Wetland Loss. Removal of 2.8 acres of wetlands, pond, and large riparian trees under alternatives A, B or C would have significant impacts on wildlife. Filling and encroaching into the pond would eliminate the shallow mudflats used by migrating shorebirds, fish and amphibians. Loss of the mudflats would also reduce insect production, which is necessary for juvenile ducks during their first seven to ten days of life. Loss of the small pond under Alternatives A, B and C would eliminate a duck nesting and brood rearing site and habitat for migrating birds such as snipe that seek out isolated small bodies of water, amphibians, and insects. Loss of amphibians and insects reduces food sources for predators such as the great blue heron, and insect eaters such as swallows and flycatchers. Elimination of canarygrass would reduce the seed food source and cover for summer birds such as pheasant. It would also eliminate a winter feeding area for dabbling ducks. Loss of the large trees would remove nesting and perching habitat for a variety of smaller passerine birds and raptors. 50 Sedimentation will impact the aquatic insect populations for short periods. Alternative D implementation would also result in a significant wildlife impact due to habitat elimination. Filling of wetlands and elimination of trees along the north side of the railroad track and the southwest corner of the pond would reduce wildlife use similar to other action alternatives, although to a lesser degree because encroachment is less. Alternative E, no action, would continue existing plant and animal use; no direct impacts would occur. Secondary Impacts Construction. Short -term impacts from construction activity under all action alternatives would include noise disturbance from construction equipment, light and glare if work is conducted at night, and the potential for increased sediment from the placement of material into the pond. If work is completed during winter months, the impacts would be greater since this is the period of highest waterfowl use. Since a majority of waterfowl activity,is concentrated in the southwest and west portions of the pond the noise impacts would be greater in this area than in the southeast end of the pond and wetlands. Work in the summer would have a greater impact on the east end as the wildlife activity in that area is mostly nesting and other summer uses. Impacts to waterfowl would be increased if the upland area along the west end of the pond is used for equipment parking or maintenance, or materials storage. Road;Operation. A significant secondary plant and animal impact for all action alternatives is the increased potential for Tukwila Pond property development due to improvement in property access from the new roadway. The Tukwila Pond property is zoned C -P which is the designation for a "Planned Business Center ". Improved site access resulting from all action alternatives will increase the likelihood of such a development to some degree. This type of development, depending on what is approved, could have significant plant and animal impacts. The impact potential is also dependent on the degree of plant and animal mitigation implemented for the South 168th Street project. It should be noted that developer interest in the pond property has been strong even without the proposed roadway. 51 Traffic noise and light glare resulting from implementation of Alternatives A, B or C would be significant because of the close proximity to the open water and the lack of an adequate physical and visual buffer between traffic and wildlife using the pond. Species such as canvasback, that are less tolerant of human activity, would probably cease to use the pond. Others would shift their use pattern to other areas of the pond and possibly leave. The reduced size of the crescent - shaped pond and the close proximity of the north traffic lanes to the remaining water would create stress that would eliminate most use except for highly gregarious birds such as mallards, house sparrows, starlings and other urban dwellers. The closeness of traffic to the willow stand in the southeast corner would increase pressure on birds that now nest in the trees. It is expected that most birds, especially the nonmigratory species displaced from the road site, would relocate in the valley. Some of these birds may leave the Tukwila area and not return. The effects on the bird use of the pond would impact flight patterns from the Green River. Birds that now include Tukwila Pond in a daily use pattern would shift to other areas, creating increased competition for food, cover and loafing space on the limited open water areas in the valley. The impacts of Alternative D would be less than A, B or C because of its increased distance from the pond edge and the willow stand in the southeast corner. Activity in the small pond would still he limited; however, with the existing tree cover there is protection for nesting waterfowl and even secretive birds such as rails and snipes. Canvasback would still probably leave the site, but the other ducks would remain, possihly in lower numbers. Human access along the road would have less overall impact than cars and road noise, if only because of the expected limited use. If use along Andover Park West is typical of what would occur, the disturbance would be limited. However, because of the close proximity of the road and sidewalks to open water, human use would move the birds away from the south bank where the shallow mudflats occur. Note that Alternatives A, B and C would not have a sidewalk on the north side of the road initially. However, enough right -of -way for a sidewalk has been allowed for these alternatives. In contrast, Alternative D has proposed sidewalks on both sides of the 52 street. Human presence closer to the pond could result in: (1) the throwing of rocks, trash, etc., into the pond or at birds which would cause a disturbance by disruption, and (2) feeding of birds could create a semi - tame population of mallards and mallard- domestic crosses to become the dominant species in the pond. With Alternative D, noise would be as intense, but the ability of people on the sidewalks to influence activity on the pond would be less. Litter' and harrassment would not lessen, but the limited contact with the water's edge would give the birds more escape area and reduce the floatable trash. Alternative E, no action, would continue existing plant and animal use until the Tukwila Pond property is developed. Impacts Conclusion From a biological perspective, Alternative D would be the least impacting of the action alternatives, both in habitat lost and the indirect Impacts from noise, light glare and human activity. It would also be the least impacting to the functional wetlands values as it reduces less of the wetland detention /retention and biofiltering area. Possibly the greatest secondary impact to plants and animals would be the slightly increased potential for development of the remaining portion of the Tukwila Pond property due to the improvement of access to the property With all action alternatives, the biological and hydrological values of the wetland and pond will be reduced, depending on the degree of mitigation implemented. Mitigating Measures • Dense riparian and deciduous trees will be planted on the slope easement as shown in Figure 19. This will discourage casual pedestrian intrusion into the pond area, minimize spillover from street lights and provide replacement resting /nesting areas. 53 • The total wetland area lost (including the wet meadow, riparian edges, and pond) will be replaced on -site and /or off - site. The location and type of wetland area to he provided will he dependent on the present availability and capability of sites that can be enhanced to sufficiently offset losses associated with impacts of the South 168th project. While not a mandated requirement, wetland area will be replaced within one year of commencing road construc- tion unless mitigation is tied to a larger wetland enhancement project. However, in no case shall wetland replacement be delayed longer than five years. • The sidewalk will be placed as much as possible over the existing power trench. This would shift the road to the south by about 5 feet. The maximum 15 -foot railroad clearance would he retained. • The proposed landscaping vegetation will be increased by planting a tree /shruh mix on the road fill slope to provide a light buffer and limit human interaction with the pond. Spacing would give a filtered view access to the pond hut keep interference impacts lower. • Street light glare onto the pond site will be reduced through such measures as locating all street lights on north side of roadway facing south, and placing reflectors to shield pond site from direct lighting. • Construction impacts will be mitigated by utilization of silt curtains at the edge of the pond to isolate any dirt from the pond. This will be included in the small pond as well. Unavoidable Adverse Impacts Construction activity will eliminate riparian, upland and wetland vegetation and will displace birds and small mammals. The long -term impacts to plants and animals will depend on the degree of mitigation implemented. Wildlife supported by this habitat would he destroyed, would relocate into other portions of the pond, or would relocate to other sites where adequate habitat now exists or where wetland replacement has occurred. 54 • e 'GROUND COVER TYPICAL MODIFIED LANDSCAPE SECTION N.T.S. CITY OF TUKWILA. WASHINGTON ENTRANCO ENGINEERS. INC. SOUTH 168TH STREET Figure 19 Roadway & Landscape Proposal for Wetland Mitigation 55 BUILT ENVIRONMENT NOISE Existing Conditions Environmental noise is measured in decibels A- weighted, abbreviated dB or dBA. The A- weighting is a frequency - dependent level adjustment . that is based on the sensitivity of human hearing at various sound frequencies and takes into account the human ear's lack of sensitivity to low frequencies. A doubling of judged loudness occurs for each 10 dBA increase in level. For example, RO dBA is judged to be twice as loud as 70 dBA and four times as loud as 60 dBA. Table 2 shows various A- weighted sound levels and typical human responses. Noise levels usually represent a statistical "average" over a specified period of time. The standard descriptor is designated by "L" and represents the noise levels exceeded during a specified percentage of time. The descriptor used in the U.S. Environmental Protection Agency (EPA) guidelines is the Ldn, which is the 24 -hour average sound level with a 10 dBA weighting for night sound levels. EPA guidelines to evaluate Ldn noise impacts are shown in Table 3. The EPA guidelines also specify the information needed to evaluate noise impacts and some abatement measures that can he used if abatement is required. The proposed roadway is located in a light industrial, commercial and industrial park area with several noise - producing activities. Noticeable noise sources are heavy trucks and rail traffic serving Parkway Square, the Bon Distribution Center, the Boeing Company (TCW) and other businesses. Noise for vehicular traffic also occurs on both Southcenter Parkway and Andover Park West. Although no measurements were taken for this study, noise levels were monitored at three locations in 1979. Noise levels in 1979 were 60, 62 and 59 (Ldn) for the west, north and east sides of Tukwila Pond, respectively. The Parkway Square Shopping Center was under construction at that time; apparently this affected the reading on the west side (City of Tukwila, 1979). Adverse noise levels existed on the entire site based on these earlier measurements, compared to Table 3 criteria. It is reasonable to assume they are relatively the same under current conditions. 57 Activity Carrier Deck Jet Operation 50 HP Siren (100 feet) TABLE 2 Sound Levels and Human Response Jet Takeoff (200 feet) Riveting Machine Jet Takeoff (2,000 feet) Farm Tractor Heavy Truck Food Blender Pneumatic Drill (50 feet) Garbage Disposal Car, 65 mph (25 feet) Freight Train (50 feet) Vacuum Cleaner (10 feet) Freeway Traffic (50 feet) Large Store Air Conditioning Unit (20 feet) Light Auto Traffic (100 feet) Living Room /Bedroom Library Soft Whisper (15 feet) Broadcasting Studio Sound Level, dBA Response 140 Threshold of Pain 130 Limit Amplified Speech 120 110 100 Maximum Vocal Effort Conversational Relationship Shouting in ear Very Annoying 90 Hearing Damage Shouting at 2 feet (8 hours) 80 Annoying Telephone Use 70 Difficult 60 Intrusive 50 Quiet 40 30 Very Quiet 20 10 Just Audible 0 Threshold of Hearing Very loud conversation, 2 feet Loud conversation, 2 feet Loud conversation, 4 feet Normal conversation, 12 feet 58 TABLE 3 U.S. Environmental Protection Agency 'Noise, Impact Guidelines Noise Level (Ldn) Noise Impact Less than 55 dBA 55 to 65 dBA 65 to 70 dBA Levels are generally acceptable; no noise impact is generally associated with these levels. Adverse noise impacts exist; lowest noise level possible should be striven for. Significant adverse noise impacts exist; allowable only in unusual cases where lower levels are clearly demonstrated not to he possible. Greater than 70 dBA Levels have unacceptable public health, and welfare impacts. Impacts and noise increases over present amhient levels are classified as follows: 0 - 5 dBA slight impact 5 - 10 dBA significant impact >10 dBA very serious impact Environmental Impacts Noise impacts will occur to the same degree for all alternatives on a short -term basis from construction activities, and on a long term basis from traffic operation. Short term noise impacts would occur with the operation of equipment during the six -month construction period of the project. Noise levels could vary from 70 to 95 dBA in the immediate vicinity of the project construction area. Some higher peaks could occur if impact equipment, such as jackhammers, are used. Construction noise would be confined to daytime hours and would cease when the project was completed. 59 A new roadway would relieve congestion on Strander Boulevard to the north and Minkler Boulevard and South 180th Street to the south without increasing the volumes of traffic to the entire Superblock area. Noise levels produced by existing traffic would be redistributed. Long -term increases in traffic noise levels would occur in the immediate vicinity of the new roadway. Average daily traffic on the new roadway would be between 6,5(10 and 11,000 vehicles per day. Noise impacts, which increase greatly with increased vehicle speeds, would be minimized for an arterial street due to the signed speed limit of 35 miles per hour for all alternatives. Due to the traffic volumes, speeds' and adjacent commercial /industrial land uses, noise levels along the proposed South 168th Street would increase. This would have a slight impact on the adjacent industries and commercial businesses, hased on EPA guidelines (Table 3). A previous noise analysis for a Tukwila Pond property development (City of Tukwila, 1979) predicted a 1 to 3 (Ldn) noise increase in the project vicinity based on an increase in traffic of 28,000 vehicle trips per day and other sources for that project. This compares to the aforementioned range of 6,500 to 11,000 per day for South 168th Street. Increased traffic noise impacts to the wildlife in the pond area are discussed in the Plants and Animals section of this EIS. Noise levels in the Strander Boulevard and proposed Minkler Road areas would decrease slightly due to reduced congestion on these streets. Conversely, slight noise increases may be realized on Andover Park West due to traffic increases from all alternatives. Alternative E, no action, would continue existing noise levels in the project area; these are estimated currently in the high 50's to low 60's (Ldn). Mitigating Measures Mitigating measures to reduce short term noise impacts due to construction might include limiting construction to normal working hours; using electric rather than gasoline or diesel - powered machinery whenever possible; placing acoustic screens around particularly noisy machinery; fitting pneumatic equipment and internal combustion engines with mufflers;and, turning off idling equipment. No mitigation is proposed for increased traffic noise. 60 Unavoidable Adverse Impacts Construction activities would result in some level of short term impacts from equipment operation over a six -month period. There would he an increase in present noise levels to adjacent properties after project completion due to new traffic along South 168th Street. LAND USE Existing Conditions This section describes the existing land use, zoning and projected land use in the vicinity of the project area. The proposed South 168th Street is located in what is commonly referred to as the "superblock ", bounded by Andover Park West, Strander Boulevard, South 180th Street and Southcenter Parkway (Figure 1). Existing land use (Figure 2) to the north of the proposed South 168th Street is 'commercial, with Parkway Square on the west end and a vacant tract of 'land, approximately 39 acres in size, referred to as "Tukwila Pond" to the east. Tukwila Pond is a 19.5 -acre pond formed by regional drainage and is surrounded by 4.6 acres of wetland and 1.9 acres of riparian land. Several development plans have been proposed, but not implemented. Some development of the property has occurred, as evidenced by filling on the north and west sides of the pond. There are no-other indications of development on the site. The existing undeveloped state of the Tukwila Pond property differs greatly from the high intensity commercial use envisioned for the site in the Tukwila Zoning Code (CP-- Planned Business Center). South of the proposed street, the land use is currently zoned for CM -- Industrial Park, with Allied Stores,Distribution Center (Bon Warehouse) on the west end and the Southcenter Corporate Square or "TCW" (Boeing Computer Services) to the east. Areas adjacent to and in the proposed South 168th Street right -of -way are used for access to existing buildings, parking, loading, and unloading. There is a Puget Power power trench running. parallel to and immediately south of the proposed South 168th Street alignment, and an aviation fuel line running from Renton to Seattle- Tacoma International Airport which crosses the proposed alignment along the eastern edge of Southcenter Parkway. 61 A Union Pacific Railroad spur line runs from Andover Park West parallel to the proposed alignment and divides into two industrial spur tracks to service the Bon Warehouse. These tracks are used for spotting and unloading rail cars. Tukwila Zoning Code Land use impacts resulting from the proposed roadway are influenced by zoning designations of adjacent properties. If existing developed properties do not conform to zoning designations as a result of the proposed roadway, they become legally nonconforming uses. However, undeveloped property (e.g., the Tukwila Pond parcel) would have to develop in conformance with the zoning code. Zoning code stipulations for street setbacks, landscaping and parking for existing adjacent land uses are described below. , Zoning. Properties to the north of the proposed roadway are zoned CP-- Planned Business Center while properties to the immediate south are zoned CM-- Industrial Park, according to the Tukwila Municipal Code (TMC), Title 18, Zoning. Area zoning is shown in Figure 20. The purpose of the CP zoning is to provide an area appropriate for a planned business center (Section 18.34.010, Tukwila Zoning Code). This designation allows for all regional retail business land uses (zoning designation C -2), and additionally allows for planned shopping center space in excess of 300,000 square feet of gross leasable space. Regional retail business land use provides for areas of diversified commercial /retail activities which serve a broad regional clientele and generally attracts traffic from a broad area. Permitted uses are varied and include but are not limited to: auto repair shops, restaurants, hotels, furniture stores /warehouses, job printing, commercial laundries, liquor stores, theatres, convention facilities, bus stations, business /commercial schools and wholesale /retail sales offices. The purpose of the CM zoning (Industrial Park) is to provide for, "light industrial uses which are non - nuisance activities in terms of air and water pollution, noise, vibration, glare and odor" (Section 18.38.010, Tukwila Zoning Code). Permitted uses include those which manufacture or process a wide variety of foods, pharmaceuticals and electronic or precision instruments; package or process previously prepared metals and materials, 62 ot■ NORTH • ii!14 ! i=7,111111111111111111-- c4.4 gCM 1-51 C-M C-2 C-M • " C-M C-M now,. M-2 - P-A M-2 e i. C-21 4 • M.4 7.7K :1lZr--V-= _ V 1 W;1 .1C.L NA-1 CITY OF TUKWILA, WASHINGTON Figure 20 CITY OF TUKWILA ZONING 63 including clothing, furniture, plastics, etc.; warehouse storage and wholesale distribution facilities; body or engine repair shops; commercial, professional and business offices and services; railroad tracks and spurs; commercial and public recreational facilities; and other compatible uses of a light industrial nature, as well as business and retail uses. Existing uses at or adjacent to the project site are compatible with existing zoning. Building Setbacks. The purpose of building setbacks is to ensure adequate light, air and open space quality for the general health, safety and welfare of the public. The Board of Adjustment may adjust the requirements where it deems necessary to recognize special conditions through a variance procedure. Setbacks for the project area zones CP and CM are shown in Tahle 4. TABLE 4 Setback and Landscape Area Requirements* Setback Requirements ** Required Landscaping Area Zoning Front Side Rear District Yard Yard Yard CP 20 feet * ** 10 feet 20 feet CM 50 feet 5 feet 5 feet CP 15 feet 15 feet 15 feet CM 15 feet 5 feet None * Based on Chapter 18.52.020 - Tukwila Zoning Code - 1982. ** Based on Chapter 18.50.050 - Tukwila Zoning Code - 1982. * ** For structures less than 20 feet in height. Landscaping. The purpose of landscape requirements is to establish minimum requirements for landscaping to promote safety, to provide screening between incompatible land uses, and to mitigate adverse effects of development on the environment. Project site landscape requirements are shown in Table 4. 64 Other landscape requirements outlined in Chapter 18.52.040 require that landscaping not obstruct views from or into the driveway, sidewalk or street. Utility easements and other similar areas between property lines and curbing shall be landscaped and /or treated with dust and erosion control planting or surfacing such as evergreens, groundcover, shrubs, trees or sod, or a combination of similar materials. Off- Street Parking and Loading. The purpose of off - street parking and loading regulations is to provide for adequate, convenient, and safe off- street parking and loading areas. General requirements include limitations on location, minimum parking area dimensions, slope, driveways and maneuverability, surface materials, lighting, curb -cuts and obstructions. The required number of parking spaces and parking area dimensions for properties adjacent to the project are provided for in TMC Section 18.56.050. This is generally 2.5 spaces for each 1,000 square feet of commercial or office space and 1 space for each 1,000 square feet of industrial space.. Off - street space for standing, loading and unloading services is to he provided so as not to obstruct freedom of traffic movement on streets or alleys. For all office, commercial, and industrial land uses, each loading space is to consist of at least a 10 -foot by a 30 -foot loading space with a 14 -foot height clearance for small trucks, or a 12 feet by 65 feet loading space with 14 -foot height clearance for large trucks (Chapter 18.56.060). The number of spaces required is based on the gross floor area of the building.' Comprehensive Land Use Policy Plan, City of Tukwila The existing City of Tukwila Comprehensive Land Use Policy has a direct bearing on the proposed roadway. The Comprehensive Land Use Policy Plan lists "general goals" and five "element goals" for long range planning. The element goals are more specific in that they relate to single elements. Two elements are discussed as they relate to this project: Transportation /Utilities and Natural Environment. Transportation /Utilities. The Transportation /Utilities element includes the following goals: providing an adequate transportation system capable of moving people and goods in a manner consistent with compatible land use patterns, and assurance of a public service level consistent with the needs and desires of the community. 65 The basic concepts that are emphasized in the Transportation /Utilities element are (1) a systems approach to transportation and utilities consistent with planned land use, and (2) planning and foresight in the construction and maintenance of facilities. Specific transportation objectives that are applicable to the proposed project include providing for user safety while allowing efficient movement of traffic. This objective supports a broad approach to roadway improvements that consider the circulation impact on planned land use patterns. Specific transportation policies that apply to the proposed project include: • Minimizing conflict between moving traffic and parked vehicles; ensuring that road design either eliminates parked vehicles from the roadway section or assures that such vehicles would not . interfere with the flow of traffic. • Discouraging the maneuvering of automobiles or trucks on public rights -of -way. • Dedicating adequate and acceptable rights -of -way at the time of land subdivision. • Encouraging effective construction techniques and good design principles. • Discouraging single - purpose road construction and improvement projects, preferring coordination with other street improvements such as sidewalks, underground utilities and landscaping. • Classifying roadways according to the adjacent land use and service area of the roadway. • Minimizing the adverse environmental impacts of existing and future roadways on the natural environment. Railway policy indicates that railroad lines and spurs should he functionally related to the areas through which they pass and should promote desired development patterns. Another policy is to encourage use and operation of localized rail lines to coincide with periods of low 66 traffic flow, therehy restricting rail traffic during peak hours. Finally, rail lines are to he located in corridors to reduce the number of grade crossings and to reduce access to and usahility problems of the land located adjacent to and between such lines. Natural Environment. The natural environment element includes the following goals for long -range planning: gauge development of the land in a manner suitable to the natural environment, wisely use and preserve the natural features and resources of the physical environment, and protect and enhance the natural amenities and aesthetic resources of the Tukwila area for the public's welfare. Specific natural environment objectives that may be applicable to the proposed project include: (1) promoting retention and installation of vegetation; (2) promoting retention and preservation of certain highly suitable areas for wildlife habitat and natural areas; (3) realizing the abilities of natural streamways, ponds and marshes to handle storm runoff while acting as significant natural amenities; and (4) recognizing the environmental basemap of the Tukwila Planning Area, which is used as a general planning guide in the Tukwila Comprehensive Land Use Policy Plan. The Tukwila environmental base map identifies Tukwila Pond as an area noted for, its open water /wetland character. This attribute results in the Pond being shaded the lightest of four shades of green on the map. This map states "Endemic to the policies of the Natural Environment element is the preservation of the amenities shown here: logically, the darker the area, the more critical the need for preservation." Specific policies that apply to the proposed project include: • Encourage the use of live vegetation in development landscape plans. • Strive to retain viable areas of wetlands for wildlife habitat. • Encourage the preservation of marshes and ponds for the retention of stormwater runoff. The City of Tukwila Comprehensive Land Use Plan map indicates the "superblock" as an area designated for commercial and light industrial use. It also depicts the Tukwila Pond portion as having "Special Development Considerations ". This refers to the area of water surface and does not preclude development. Rather, it depicts areas where urban 67 development must respond sensitively to certain environmental factors (City of Tukwila, 1977). How to "respond sensitively" with regard to Tukwila Pond for this project is initially defined in the "Plants and Animals" mitigation sections of this Draft EIS. Previous site development conditions, as defined in City Council Resolutions 656 and 736, are not applicable to this project (Collins, December 16, 1985 personal communication). The proposed project is consistent with the Tukwila Comprehensive Plan and Zoning Code. Shoreline Designation The project site has not been designated as a shoreline under any Shoreline Master Program. Environmental Impacts Several impacts resulting from the proposed project will be common to all the action alternatives and options. These are described below. Where impacts are specific to a particular alternative and /or option, they are so described. Zoning and Land Use Policy. The proposed South 168th Street would be a compatible use consistent with current zoning of the site and consistent with the adjacent Planned Business Center and Industrial Park (CP and CM) zones as outlined in the Tukwila Zoning Code. Project design for all alternatives will be compatible with the off - street parking and loading requirements of the Tukwila Zoning Code. The project will also be consistent with the applicable provisions of the Comprehensive Land Use Policy Plan, as discussed above. Right -of -Way. Currently no right -of -way (ROW) exists along the proposed South 168th alignment. The City of Tukwila subdivision code states that the minimum right -of -way for a local street in a commercial/ industrial area is 60 feet, with 48 feet of pavement. The current City sidewalk ordinance requires sidewalks to be a minimum of 6 feet on both sides of pavement. A sixty -one (61) foot minimum is required for curh and gutter, sidewalk, and pavement. 68 The Parkway Square Binding Site Improvement Plan shows a 30 -foot easement over the southern portion of the Parkway Square property, which reads as follows: Thirty (30) foot easement in favor of the City of Tukwila for access, utilities, and the right to construct related improvements . by the City. If City does not make use of this easement within 10 years of the effective date of this Binding Site Improvement Plan, easement will be void and all rights will revert back to owner of Parcel C. The site plan was filed with King County on December 5, 1979; therefore the City must make use of the easement by December 1989. Right -of -way acquisition will he necessary for the entire length of all alternatives. A minimum of 61 feet of ROW was used in planning the roadway (Entranco Engineers, 1986). Right -of -way requirements for all action alternatives are summarized in Table 5. Alternatives A and B are similar in their ROW needs for all adjacent properties except the Bon Warehouse, where about 7,000 more square feet is needed for Alternative A due to its four lane width. Alternative C is similar to B with the exception of its impact to Parkway Square where it needs about 5,000 more square feet since the service drive is eliminated. Alternative D requires the most ROW of properties to the south and the least ROW to those properties to the north due to its southern alignment. The land required for the ROW will not include any buildings. Current use of land for right -of -way includes landscape buffers, driveways, parking and undeveloped land which provides wildlife habitat. Both PSPL and the Union Pacific Railroad have easements that would need to be revised. Federal funds are not anticipated for this project. However, should such funding he used, then the procedures of the Uniform Relocation Assistance and Right -of -Way Acquisition Act, RCW 8.26, would be followed. The City of Tukwila has adopted RCW 8.26 procedures to acquire right -of -way for projects involving federal funding. These procedures require that an appraisal of the property be made and that the appraisal follows a proper methodology. The City has to make a bona fide offer to pay the fair market value (appraised value) for the property prior to bringing any condemnation action. A summary of the City's land condemnation process is in Appendix C. This process would be used in all condemnation proceedings as indicated by. State law. 69 TABLE 5 Approximate Right -of -Way Requirements (Square Feet) Alternatives A B C D Bon Warehouse 27,460 21,705 20,915 39,850 Parkway Square* 14,500 14,500 19,910 19,330 TCW 3,62.5 3,625 3,625 19,820 Tukwila Pond 74,260 74,260 73,970 41,200 TOTAL 119,845 114,090 118,420 120,200 * Parkway Square existing easement is 18,595 square feet. Building Setbacks. The building sethack for each property along the four action alternatives is shown in Table 6. In several cases, the minimum building setbacks will be less than zoning regulations (see Tables 4 and 6). This includes Parkway Square for all alternatives, the Bon for Alternative D, and TCW for all alternatives. In all cases, the existing buildings would become legally non- conforming strictures. Any new development on these and the Tukwila Pond property would be required to conform to all the development requirements as specified in the Zoning Code. Landscaping. Landscape design is intended to enhance the proposed South 168th Street and contribute to the overall streetscape theme in the City of Tukwila. Landscaping and roadway design are shown in Figures 4 through 15. 70 TABLE 6 Building Setbacks Under Each Action Alternative (feet*) Alternatives Property (Zone) A B C D Bon Warehouse (C -M) 58 58 58 31 Parkway Square (C -P) 5 ** 5 ** 11 9.5 TCW (C -M )_ * ** 44 44 44. 18 Tukwila Pond (C -P) N/A N/A N/A N/A * Building to edge of right -of -way. - ** Most of the length of building is 26.5 feet from edge of right -of -way. * ** Wood storage shed. The project includes the following areas that will require specific design attention for all action alternatives: • Roadway entries at Southcenter Parkway and Andover Park West. - Strreet trees will he clustered at these entries to identify access points. • Roadway identification and enhancement - Street trees will be located along the north and south alignments in select places as described below. • Tukwila Pond re- establishment and enhancement - Tukwila Pond fill would create a slope easement which will be revegetated (see Plants and Animals section of this chapter). 71 • Visual separation between the roadway and adjacent land uses - Where adequate room exists, trees will be located to visually screen the light industrial land uses north and south of the alignment. • Compliance with the City of Tukwila landscape requirements. Landscaping as it affects aesthetics is discussed in the Aesthetics section of the EIS. Railroad Impacts. Alternative D is the only action alternative that would require changes to the existing railroad facilities. One of the rail spurs that currently serves the Ron Warehouse would be eliminated due to the southerly alignment of Alternative D. This would significantly limit the amount of rail freight into the Bon Warehouse by precluding adjacent rail car unloading. The track crossing Andover Park West would have to be relocated onto the TCW parking lot for the same reason. This would result in limiting hours of access for train movement. (Impacts to TCW parking are discussed in the next section.) Loss /Relocation of Parking. All action alternatives will alter existing car and /or truck parking spaces on adjacent properties. Alternative E, no action, would continue the existing situation for adjacent developed land use; no change in parking would occur. Table 7 summarizes adjacent land use lost and changed parking spaces for cars and trucks under the four action alternatives. All action alternatives have similar impacts to car parking spaces for the TCW property except Alternative D, which would have a relocated rail spur placed in the parking lot. Lost car parking for the Bon Marche property would be similar for action Alternatives A and R. Alternatives C and D would not eliminate these car spaces due to the northward shift in the roadway alignment. The impact to the Bon's truck parking spaces is significantly different between alternatives. There are 23 existing truck parking spaces on the north side of the Bon. The length of the combined apron and parking stall is about 105 feet for most of these spaces, although aerial photos show that a maximum size truck /trailer rig can be docked in about 95 feet of space. Action Alternative D would shorten all 23 existing 105 -foot spaces by about 23 feet (Table 7). This would significantly hinder use of the maximum size truck /trailer rig for moving freight since the spaces would he 72 about 82 feet in length. This could necessitate changes in the external and /or internal warehouse operations (see Scoping comments in Appendix A). This space would allow an adequate parking stall (City Zoning Code requires a minimum of 65 feet of space for commercial truck stalls and 30 feet of space for pick -up truck stalls), hut it would not allow enough apron space for maneuvering maximum size rigs. TABLE 7 Parking Space Impacts ACTION ALTERNATIVES A B C D Lost Lost Lost Lost Car Spaces Car Spaces Car Spaces Car Spaces Property Spaces Changed Spaces Changed Spaces Changed Spaces Changed Bon Marche 12 7(c) 12 5(d) 0 5(e) 0 23(f) Parkway Square 14 0 14 0 14 1(g) 3 1(g) TCW 0 3(a) 0 3(a) 0 3(a) 6 3(a,h) (a) 3 car spaces relocated (h) Rail spur relocated onto parking - 6 car spaces eliminated (c) Shorten truck apron 1 to 10 feet for 7 spaces (d) Shorten truck apron 1 to 3 feet for 5 spaces (e) Shorten truck apron up to 23 feet for 5 spaces (f) Shorten truck apron up to 23 feet for 2.3 spaces (g) Service drive to south of building eliminated In comparison, Alternative C would shorten 15 of the 23 truck parking spaces yip to 23 feet. Nine of these 15 spaces would be less than 95 feet long, which is below the shortest existing truck space length. The other 6 would be less than 105 feet in length. Impacts to the external and /or internal warehouse operations are likely to be similar to Alternative D. 73 Action Alternative A would shorten 7 spaces of the Bon's truck parking. Two of these 7 spaces on the northwest side of the Bon's building are not currently used for maximum size rigs. All 7 spaces would he shortened up to 10 feet and would still equal or exceed 95 feet in length. Alternative B would shorten 5 spaces of the Bon's truck parking. Again, two of these are not used for maximum size rigs. The 5 spaces would he shortened 1 to 3 feet and would still equal or exceed 102 feet. Both of these action alternatives would likely cause modifications in the current operation of truck parking. For example, the limited space may necessitate the tractors not he left attached to trailers once docking is completed. Parkway Square has 14 car parking spaces eliminated for Action Alternatives A, B, and C and 3 car spaces for D. Both Alternatives C and D eliminate the present service drive to the south side of the Parkway Square building. Table 8 provides an estimate of the maximum impacts to adjacent properties' ultimate development potential based on the amount of development supported by one parking space. This assumes no conversion of full sized spaces to compact car spaces. Mitigating Measures For all action alternatives the roadway has been designed to minimize the impact on building and landscape setbacks. Wetland habitat replacement will occur to comply with Comprehensive Land Use Policy (see Plants and Animals); this could require purchase of some undeveloped land from the Tukwila Pond property. Parking replacement for affected properties could occur to mitigate the loss; this would require acquisition of some of the adjacent Tukwila Pond property or Doubletree Plaza. Condemnation and compensation is also an option. Unavoidable Adverse Impacts For all action alternatives, there will he environmental tradeoffs between developed and natural land uses. Natural habitat will he displaced to allow for the roadway and developed land mitigation. Some developed land uses may be precluded by the retention /replacement of natural habitat on the Tukwila Pond site. Estimated parking and development potential impacts are shown in Tables 7 and 8, respectively. 74 TABLE 8 Maximum Impacts to Development Potential Resulting from Parking Loss Parking Spaces: Current (1) After Project is Built Net Loss (4) Structure Size (square feet): Existing (1) Current Development Potential (3) Development Potential After Project is built Net Loss of Development Potential Notes: Bon Marche Parkway Square TCW 360 366 184 348 352 178 12 14 6 150,000 360,000 348,000 12,000 92,000 146,400 140,800 5,600 59,811(2) 73,600 71,2.00 2,400 (1) Source: Vernon Umetsu (September 10, 1986) (2) Total of three buildings along proposed ROW (building numbers 370, 555, 545). (3) Refers to maximum size of structures that could be developed on the site given the current number of parking spaces, existing use, and zoning code (TCW and Parking Square: 2.5 parking spaces per 1,000 square, feet; Bon Marche: 1 parking space per 1,000 square feet - assumes retail space relocates. (4) Source: Entranco Engineers (1986) 75 TRANSPORTATION Existing Conditions Transportation conditions and impacts have been examined in the superblock area defined by Strander Boulevard to the north, South 180th Street to the south, Southcenter Parkway to the west and Andover Park West to the east. Table 9 characterizes roadways in the project area. There are four signalized intersections in the immediate vicinity of the project which were analyzed for level of service, operations, and safety: Strander Boulevard /Andover Park West, Strander Boulevard/ Southcenter Parkway, South 180th Street /Southcenter Parkway and Andover Park West /South 180th Street. Traffic congestion problems occur at these intersections during both the noon and p.m. peak hours: • Strander Boulevard /Andover Park West - Lengthy queues were observed on the north and south approaches in the noon and p.m. peak hours. The queue occasionally blocked the driveway to and from the Southcenter Shopping Center and the Tukwila Post Office. • Strander Boulevard /Southcenter Parkway - Lengthy queues were observed in the left -turn lane of Strander Boulevard during the noon peak hour and in the right -turn lane of Strander Boulevard during the p.m. peak hour. • South 180th Street /Southcenter Parkway - A large left -turn volume from southbound Southcenter Parkway to eastbound South 180th Street was observed to cause some delay during the noon peak hour. The new South 168th Street link is listed as priority No. 9 in the City of Tukwila's 1987 -1992 Six -Year Transportation Program (TIP). Table 10 lists relevant projects in the program. Traffic Volumes and Level of'Service. Current traffic volume data was obtained for the project area from the City of Tukwila. Figure 21 shows the current 1985 average daily traffic volumes and p.m. peak hour directional volumes on the network. Noon and p.m. peak hour level of service (LOS) was calculated at the four signalized intersections. 76 TABLE 9 Existing Roadway Characteristics Right- Street Speed Functional of -Way Width Edge Limit Roadway Classification (feet) (feet) Type (mph) South 180th Street Secondary 60 60 Curh & 35 Andover Park West to Arterial Gutter Southcenter Boulevard Andover Park West Collector 60 46 Curb & 35 Strander Boulevard to Arterial Gutter South 180th Street Southcenter Parkway Secondary 72 48 -61 Curb & 35 Strander Boulevard to Arterial Gutter South 180th Street Strander Boulevard Secondary 60 50 Curh & 35 Andover Park West to Arterial Gutter Southcenter Parkway Minkler Boulevard* Collector 76 -102 48 Curb & 35 Andover Park West to Arterial Gutter Southcenter Parkway * Proposed arterial to be built in 1987 -1988. 77 TABLE 10 Relevant Projects in City of Tukwila's Six -Year 1987 -1992 Transportation Improvement Program Street South 168th Street Andover Park West to Southcenter Parkway Strander Boulevard Andover Park West Andover Park West to the Bridge 58th Avenue South Strander Boulevard to South 168th Street Southcenter Parkway I -5 Southbound Off -Ramp to Minkler Boulevard Minkler Boulevard Extension Andover Park West to Southcenter Parkway Improvement Project No. 9 Principal Improvement (And Estimated Cost) New 3 -lane street with new signals at Andover Park West and Southcenter Parkway. ($2,748,000) 17 Left -turn channelization and signal modifications. ($90,000) 26 Widen existing 4 lanes to 5 lanes. Signal revision. ($493,000) 29 New 3 -lane street. One new signal at Strander Boulevard. ($1,582,000) 27 Widen from existing 5 lanes to .6 and 7 lanes. ($2,540,000) 1 New 4 -lane street with new signals at Andover Park West and Southcenter Parkway. ($4,349,000) Year of Completion 1987 -1989 1990 -1992 1990 -1992 1990 -1992 1990 -1992 1987 -1988 78 S. 168TH ST. eee. eeee eeeeee eeeeeeeeeeeeeeeeeeeeueeeeeea PROPOSED MINKLER BLVD. EXTENSION Average Daily Traffic (000) 400 P.M. Peak Hour Volumes LOS,/ Noon Peak Hour P.M Peak Hour A.M. Peak Hour Values 490 " ui 230 C ENTRANCO ENGINEERS, INC. NORTH SCALE: 1" = 800' CITY OF TUKWILA, WASHINGTON ' /Note: Level of Service at Southcenter Parkway /Strander Blvd. and Andover Park West/Strander Blvd. based on Highway Opacity Manual, 1985; all others based on TRB Circular 212; see text. Figure 21 EXISTING TRAFFIC CONDITIONS 79 LOS can he calculated by several methods; those used here include the methods from the 1985 Highway Capacity Manual (HCM) and the Transportation Research Board (TRB) Circular 212. The TRB method usually yields a higher (better) LOS for complex multi -phase intersections. The HCM method allows calculation of the cycle length and average vehicle delay time for different intersection approaches and yields the best quantitative measure for signalized intersection flow performance. The intersections of Southcenter Parkway and Andover Park West with Strander Boulevard are in close proximity to the proposed roadway. These intersections were analyzed using the HCM method to define LOS and average vehicle delay time for several approaches. Table 11 summarizes existing conditions for several approaches. Table 11 summarizes existing conditions for these key intersections. Overall LOS values are E and F in the noon peak hour and C and 0 in the p.m. peak hour for the intersections of Southcenter Parkway/ Strander Boulevard and Andover Park West /Strander Boulevard, respectively. LOS D is generally considered to he an acceptable value in urban areas. Figure 2.1 also shows the existing LOS at the intersections. Traffic Safety. Traffic accident data was obtained in the project vicinity from the City of Tukwila for the 33 month period from February 1983 to November 1985. Table 12 shows the total and average annual accidents at various locations. In general, the accident rates are fairly low and there are no safety related problems. It should he noted that the relatively high accident rate on Southcenter Parkway between Strander Boulevard and the proposed Minkler Boulevard Extension is due to the high traffic volumes and numerous turn movements to and from access driveways in this section of roadway. Without an existing traffic signal between Strander Boulevard and the proposed western terminus of the Minkler Boulevard Extension, drivers have a fairly direct route of travel in which they may pick up speed easily without interruptions. This section of Southcenter Parkway has an average annual total of 16.7 accidents per year, which corresponds to an accident rate of 3.8 accidents per million vehicle miles. This accident rate is considerably higher than the average state -wide accident rate of 1.7 accidents per million vehicle miles from 1982 to 1984. Public Transportation. There are currently four major bus routes serving Tukwila in the project vicinity (Figure 22): • Route 150 serves downtown Seattle, Tukwila, Southcenter, Kent and Auburn with 34 daily runs in each direction. 80 TABLE 11 Level of Service and Average Vehicle Delay Time for Intersections of Strander Boulevard with Southcenter Parkway and Andover Park West NOON P.M. 1990 1990 1990 1990 Intersection Approach Existing Without Project With Project Existing Without Project With Project Southcenter Parkway/ Overall E* E 0 C C C Strander Boulevard 44 ** 46 26 22 2.3 2.1 Westbound F F' E D D D 165 191 57 39 40 33 Northbound C C C C C C 18 19 20 17 19 19 Southbound C D C C C C 24 25 24 23 23 22 Andover Park West/ Overall F F F D E F Strander Boulevard 71 76 104 35 53 75 Easthound E E D D D D 48 41 35 32 32 31 Westbound E E F D D D 41 47 152 34 37 36 Northbound D D E D F F 31 33 51 36 80 137 Southbound F F F D- E E 150 166 163 36 5 44 Note: Calculations based on 1985 Highway Capacity Manual * Level of Service ** Average Vehicle Delay Time (Seconds) Intersections Strander Boulevard/ Southcenter Parkway Strander Boulevard/ Andover Park West South 180th/ Southcenter Parkway South 180th/ Andover Park West Mid -Block Sections Strander Boulevard (Southcenter Parkway to Andover Park West) TABLE 12 Accident Data Summary Total Accidents (Feb. '83 to Nov. '85) Average Annual Accidents Property Personal Property Personal Damage Injury Total Damage Injury Total 1 0 1 0.4 0 0.4 6 7 2.2 0.4 2.S 2.5 7 3 10 2.5 1.1 3.6 0 0 0 0 0 0 7 0 7 2.5/ 0/0 2.5/ 1.1* 1.1 Southcenter Parkway 34 12 46 12.4/ 4.4/ 16.7/ (Strander Boulevard 2.8 1.0 3.8 to Minkler Boulevard) Andover Park West 3 0 3 1.1/ 0/0 1.1/ (Strander Boulevard 0.4 0.4 to Minkler Boulevard) * Average Annual Accidents /Accident Rate (number of accidents per million vehicle miles) 82 ENTRANCO ENGINEERS, INC. NORTH SCALE: 1" = 800' CITY OF TUKWILA, WASHINGTON Figure 22 EXISTING TRANSIT SERVICE 83 • Route 155 serves Southcenter, Fairwood and Tukwila with 17 daily runs in each direction. • Route 187 serves Southcenter, Midway,`Star Lake and Federal Way with 12 daily runs in each direction. • Route 340 serves eastside communities. Southcenter Mall is a common transfer point for all four of these routes. Pedestrian and Bicycle Activity. In the project vicinity, there currently are intermittent 5 -foot sidewalks on both sides of the road on South 180th Street, Southcenter Parkway and portions of Andover Park West. There are pedestrian push buttons, signals and crosswalks at the Southcenter Parkway /Andover Park West and Strander Boulevard /Andover Park West intersections. The discontinuity of sidewalks in these locations is inconvenient and causes safety problems for pedestrians. The lack of sidewalks may also discourage the use of public transportation and noon -time pedestrian trips to restaurants and shops in the area. The City of Tukwila has recently produced the Central Rusiness District Sidewalk Plan, which has recommended sidewalk improvements to the following roadways in the project area: • Strander Boulevard - Southcenter Parkway to Andover Park West • Southcenter Parkway - Complete sidewalks from Strander Boulevard to South 180th Street • Proposed South 168th Street In addition, pedestrian crossings were recommended at the following intersections: • Southcenter Parkway /Strander Boulevard • Southcenter Parkway /Boeing - Parkway Plaza • Southcenter Parkway /proposed South 168th Street • Strander Boulevard /Southcenter Mall entrances • Andover Park West /proposed South 168th Street 84 The completion of some or all of these .projects will significantly improve pedestrian accessibility and safety to businesses in the project area. Tukwila's Long Range Park- and Open Space Plan has identified two primary bicycle /pedestrian routes in the Tukwila CBD: • Christensen Greenbelt Park Trail extends from Tukwila Parkway to South 180th Street along the west side of the Green River to the Kent city limits, to match Kent's trail on the east side of the river. On the north end, the trail is to be extended under I -405 along Southcenter Boulevard to Fort Dent Park. • South 188th Trail is planned to accommodate east -west travel, and will use South 188th Street, the proposed South 188th connector and South 180th Street to tie into the Christensen Trail and S.W. 43rd Street in Renton. Secondary bicycle and pedestrian routes for the CBD include Southcenter Parkway /Strander Boulevard, Andover Park West and South 178th Street. The South 178th Street arterial, with a 21 percent grade in some places, was considered too steep and hazardous to he signed as a primary pedestrian /bicycle route. Railroad Facilities. There are many .railroad spur tracks in the Tukwila CBD which serve commercial and industrial warehouses. Railroad spur tracks cross almost every street in the Tukwila CBD, but are used infrequentTybytrains traveling at low speeds. There are a few railroad signals across busy roadways, and generally pavement markings and signage appear to be sufficient to maintain an adequate level of safety. There is one spur track which crosses Andover Park West north of the Boeing Computer Services office complex and south of "Tukwila Pond" property to serve the Bon Warehouse. Adjacent Business Access. The Bon Marche Distribution Center has a truck loading operation on the north side of their building, adjacent to the proposed roadway. Internal building facilities are designed to accommodate the flow of merchandise from the 23 loading hays. Inbound truck traffic is routed around the building in a counter - clockwise manner. It is estimated, during the months of October and November, that the docking space on the north side of the building is used for maneuvers up to 85 4 hours of a 9 -hour operating day. The Bon is also served by a Union Pacific railroad spur with two tracks serving an off- loading area on the north side of the building. The Parkway Square Shopping Center has a service driveway on the south side of their building, adjacent to the proposed roadway. Both sanitation and building services access the shopping center on this driveway. Property owned by TCW Realty Advisors is located to the south of the proposed roadway and fronts Andover Park West. Business access is provided by a driveway on the east side of their property, entering Andover Park West. Environmental Impacts A traffic analysis for the project area was carried out for the year 1990. These forecasts were based on traffic counts taken in 1984, and results of the Tukwila micromodel effort performed for the Tranportation Improvement Plan (Entranco Engineers, 1982). Estimated 1990 daily and noon and p.m. peak hour volumes for the project network are shown in Figures 23 and 24. Noon and p.m. peak hour average vehicle delay times and LOS were calculated (Table 11) with and without South 168th Street in 1990 for the key intersections of Southcenter Parkway /Strander Boulevard and Andover Park West /Strander Boulevard. Both scenarios assume that the extension of Minkler Boulevard from Andover Park West to Southcenter Parkway will he in place by 1990. Other road improve- ments to facilitate area circulation, as shown in Table 10, have not been included in assessing impact. Table 11 shows the improvement in overall 1990 noon peak hour LOS and delay time over existing conditions for the Strander Boulevard /Southcenter Parkway intersection. This is primarily due to the expected decrease in westbound volume on Strander Boulevard and decrease in left -turn volume on southhound Southcenter Parkway. Average vehicle delay time for the noon hour westbound approach to this intersection is expected to improve about 2 minutes 14 seconds with the proposed project. P.M. peak hour LOS and delay times for this intersection are predicted to remain relatively the same with or without the project, although a slight reduction in average vehicle delays is obtained with the project. 86 SCALE: 1" = 800' 87 SOUTHCENTER MALL 1,760 790 1870 710 STRANDER BLVD. 33.3 S. 168TH ST. IIIIIII IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 1- N ccQ W cc o. a CC W 0 0 2 Q PROPOSED MINKLER BLVD. EXTENSION MINKLER BLVD. 131.2 NST 1010 PARKWAY 900 PLAZA LEGEND: Average Daily Traffic (000) 400 P.M. Peak Hour Volumes LOS'/ 920 `210 S. 180TH ST. Noon Peak Hour P.M Peak Hour A.M. Peak Hour Values 570 y 270111 x ENTRANCO ENGINEERS, INC. NORTH SCALE: 1" = 800' CITY OF TUKWILA, WASHINGTON ' /Note: Level of Service at Southcenter Parkway /Strander Blvd. and Andover Park WesVS.rander Blvd. based on Highway Capacity Manual, 1985; all others based on TRB Circular 212: see text. Figure 24 1990 TRAFFIC CONDITIONS WITH PROJECT 88 Improvements at Southcenter Parkway /Strander Boulevard are balanced by a worsening of LOS and 'delay times for the Andover Park West /Strander Boulevard intersection (Table 11). P.M. peak hour LOS is predicted to become F in 1990 with the proposed project. Delay time for the noon hour westbound approach is expected to increase about 1 minute 45 seconds. The reason for this change is the expected increase in westbound left turn volumes and overal northbound traffic approaching this intersection. However, the proposed action is anticipated to improve overall traffic circulation in the CBD. Transportation Circulation in the CBD. The proposed roadway (South 168th) will help to eliminate some of the circuitous traffic movement currently experienced in the "Superblock" and will reduce traffic volumes on Strander Boulevard. South 168th Street will eliminate excess travel time and associated environmental impacts related to vehicles destined for businesses along the mid- sections of Andover Park West and Southcenter Parkway. For example, an employee at the Boeing Computer Services complex would have a much shorter and less complex trip to one of the restaurants along Southcenter Parkway for lunch, with South 168th Street in place. The reduction in daily and peak hour traffic on Strander Boulevard is a significant benefit to the overall transportation system in the Tukwila CBD. In 1990, South 168th Street is expected to reduce daily traffic volumes on Strander Boulevard from 17,100 to 13,100. - a 23 percent reduction.. A similar reduction in peak hour volumes is expected. This reduction in volume on Strander Boulevard would significantly improve accessibility to the Southcenter Shopping Mall and other businesses, and reduce accidents on Strander Boulevard by reducing interaction between through traffic and traffic travelling to and from the driveways of Southcenter Shopping Mall and other businesses. Adjacent Business Access. Impacts to the number of truck parking spaces and docking has been addressed in the Land Use section. Action alternatives A, B, C and D would allow access to the Bon truck loading area the same as under existing conditions (e.g., in a counter - clockwise manner around the building). The propsoed roadway would have a sidewalk to the south,landscaping and a fence to separate it from the loading area. Trucks would have a driveway onto the proposed roadway for exiting the loading area for all action alternatives. 89 The service driveway on the south side of Parkway Square Shopping Center would be retained with action Alternatives A and B. It would be eliminated with Alternatives C and D, due to the northward shift in the proposed roadway. This would change the present access of service vehicles by requiring loading docks for each entrance adjacent to the south side of the Shopping Center. Service vehicles would have to access these loading docks by parking on the proposed roadway and access the building with ramps. This would not be feasible during peak afternoon traffic because the lane is needed for turns from the proposed roadway to the northbound land of Southcenter Parkway. The northern driveway from the TCW property onto Andover Park would be eliminated with all action alternatives. It would be replaced with another driveway on the north side of the property which would enter the proposed roadway. Access to southbound Andover Park West would he similar to present conditions (e.g., free right turns). Access to northbound Andover Park West would he facilitated with the proposed traffic signal on the east end of the roadway. Safety would he increased by use of the signal for northbound travel. Alternative E, no action, would continue the existing business access for all adjacent property owners. Traffic Projections and Signal Warrants for South 168th Street. Traffic projections on South 168th Street are primarily dependent upon the amount of accessibility provided to adjacent developments and the ultimate development of the Tukwila Pond property. For this analysis a "worst case" scenario was developed, including the following assumptions: 1. An estimate of maximum theoretical development of the Tukwila Pond parcel site as outlined in the Tukwila Transportation Improvement Plan (1979). This includes 300,000 square feet of retail space and 1,000,000 square feet of office space. 2. The relocation of the northernmost Boeing Computer Services driveway to South 168th Street. 3. A driveway connection to the Parkway Square Shopping Center parking lot on the east end of the lot. 4. Access /egress to and from the Bon Warehouse parking areas. Figure 25 shows the projected volumes and p.m. peak hour turning movements on the proposed South 168th Street for these scenarios. 90 SCALE: 1" = 800' CITY OF TUKWILA, WASHINGTON Figure 25 PROJECTED VOLUMES ON SOUTH 168TH STREET 91 Mitigating Measures Based on projected volumes, traffic signals will be needed at South 168th /Southcenter Parkway and South 168th /Andover Park west hy 1990. At both of these intersections, four lanes will be necessary on South 168th, providing two lanes in each direction. This will allow for separate right and left turn lanes at the intersections. At the South 168th /Southcenter Parkway intersection the two eastbound lanes will provide a second lane to allow for truck and other vehicle maneuvers into the Bon Warehouse facilities. At the South 168th /Andover Park West intersection the two westbound lanes will allow a left -turn lane into the Boeing Computer Services parking lot or a right -turn lane into the Tukwila Pond property. As described above, the proposed project is predicted to have both positive and negative traffic impacts as related to LOS and delay time at the key intersections of Southcenter Parkway /Strander Boulevard and Andover Park West /Strander Boulevard. The negative impacts to Andover Park West /Strander Boulevard can be partially mitigated through minor adjustments to the timing and phasing of the existing traffic signal at this intersection. Changes can be made to improve the LOS and average vehicle delay times hy allowing more green light time to the westbound left turn. Furthermore, the addition of left turn pockets on the north and south approaches would improve the LOS at this intersection. AESTHETICS This section describes the existing visual quality in the vicinity of the proposed project. Discussion will also include the visual impact of all action alternatives (A, B, C, D) and the no- action alternative E on the surrounding environment commonly referred to as the "superblock ". Existing Conditions The character of area development has been described in the Land Use section. The visual character of this development is typified by one and two story concrete buildings with five t� ten foot strips of landscaping and large, at -grade parking lots. The project area is visually accented by the eight story Doubletree Plaza Hotel, the five story Southcenter Place office building, and the undeveloped Tukwila Pond property (see Plants and Animals). 92 The western terminus of the proposed roadway is the five lane Southcenter Parkway while the eastern terminus is Andover Park West, a four lane road. Both roads have curbs, gutters, sidewalks and street plantings in the immediate area. Traffic volumes are very high on both roads (see Transportation). Figures 26, 27 and 28 show existing views along the proposed roadway. Environmental Impacts Discussion of potential visual impacts will combine Alternatives A through D due to the similarity of aesthetic (visual) impacts. Figure 26 VIEW FROM SERVICE DRIVE OFF SOUTHCENTER PARKWAY, LOOKING EAST 93 Figure 27 VIEW FROM RAILROAD TRACKS SOUTH OF TUKWILA POND, LOOKING WEST FIGURE 28 VIEW FROM ACCESS POINT OF PROPOSED SOUTH 168TH STREET ON ANDOVER PARK WEST, LOOKING SOUTH 94 The proposed road would increase visual access to the south side of the Tukwila Pond property to road users. The visual characteristics of this property would remain essentially unchanged in the long term since the City would revegetate the slope easement with plantings similar to what currently exists (see Plants and Animals). Mitigating Measures Planting street trees is proposed for each side of Alternatives A through D at the Southcenter Parkway intersection (Figure 26) to serve as vegetation entries for better identification of the access points in the roadway. Along the service drive, a 5 -foot landscape buffer will run between the 3- to 4 -foot high wall and the roadway curb (Figure 29). This design plan will ensure moderately high visual quality along the most western portion of the proposed alignment for the pedestrian and the vehicular traveler. The landscape design plan for the eastern portion of roadway (Figure 27 shows existing conditions) includes planting additional street trees along the south side of the alignment across from Tukwila Pond. The north side of the road' is intended to be visually accessible to the roadway traveler, so that with time and additional growth, the trees will direct views across the pond. The pond will be intermittently visible from the roadway. Urban shrubs will he planted to supplement the ground -level views and provide a continuous strip of color and texture to enhance the proposed South 168th Street. Along the southern portion of the alignment, trees will he planted with shrubs at their bases to provide a visual buffer between the roadway and the commercial warehouse receiving buildings. This, again, will serve to augment the visual quality of the proposed roadway. At the access point for South 168th Street and Andover Park West (Figure 28), there will he a cluster of street trees planted. The objective, similar to the proposed design at the Southcenter Parkway intersection, is to clarify the access point to proposed South 168th Street. Unavoidable Adverse Impacts No unavoidable adverse impacts are expected under any of the alternatives. 95 UTILITIES Existing Conditions Utilities which are present in the vicinity of the proposed South' 168th roadway include water, gas, storm sewer, sanitary sewer, a petroleum pipeline, telephone, and electrical power. Utilities which presently occupy portions of the project site include 115 kVA and 15 kVA underground power lines belonging to Puget Power. These lines run in a ground level trench, parallel to the South 168th alignment, surrounded by thermal sand for cooling purposes. A 12 -3/4 inch petroleum pipeline owned by Olympic pipeline carries aviation fuel from Renton to Seattle - Tacoma International Airport, runs along the eastern edge of Southcenter Parkway, and is 6 to 8 feet below ground level. There are private utility lines around existing developments abutting on the proposed project alignment. Environmental Impacts Construction of the proposed roadway would impact the location of water, gas, storm sewer, the petroleum pipeline, and telephone lines, and require their partial relocation and adjustment, particularly those which service the Ron Warehouse and the Parkway Square. All roadway action alternatives (A, B, C, fl) would have similar impacts. The western 600 feet of the Puget Power power trench will be affected by Alternatives A, B, and C, while Alternative D will require relocation of the entire trench. Fill needed for the construction of the roadway will allow the power trench to settle as much as 3 inches in adjacent areas. Storm drainage along the proposed South 168th alignment will increase due to the amount of fill and impervious surface created, as discussed in the Water section of the EIS. An additional water main, fire hydrants and street lighting will become necessary following construction of South 168th Street, in accordance with the City of Tukwila's Comprehensive Plan and City standards. 96 COLIE HOUGH ASSOCIATES CITY OF TUKWILA, WASHINGTON Figure 29 SOUTH 168TH STREET Typical Landscape Section 97 Mitigating Measures A storm drainage system would be installed along South 168th Street. As previously discussed in the Water section of the EIS, drainage would be routed to the P -17 channel sub - basin. A new 12 -inch water main would be constructed along the south side of South 168th and will connect with existing mains at Southcenter Parkway and Andover Park West. Fire hydrants would he placed behind the sidewalks, at 300 -foot intervals. All utilities work would be in accordance with the City of Tukwila's Comprehensive Plan and City standards. The western 600 feet of the Puget Power trench would have to be reconstructed and placed in a conduit system for Alternatives A, B, and C and the entire power trench would be placed in a conduit system under Alternative D. This will be necessary because the present cahles are notlong enough to be converted to a conduit and vault system. In addition, . the eastern portion of the cable contains splices which cannot he pulled through a conduit. Monitoring and adjustment of the trench to compensate for settlement of the fill would be carried out. Electrical power, gas, and telephone utilities would be relocated and adjusted as necessary at the intersections of South 168th with Southcenter Parkway and Andover Park West by the utility companies. Street lighting would be installed along South 168th Street at 125 -foot intervals, behind the sidewalk or 7 feet from the face of the curh. Street lighting would consist of 30 -foot light standards with 12 -foot arms, housing 240 volt, 200 watt HPS luminaires in cobrahead mountings. Further street lighting would be installed on combination traffic signal poles at the intersections of South 168th with Southcenter Parkway and Andover Park West. Unavoidable Adverse Conditions No adverse environmental impacts are anticipated. 99 REFERENCES Alpha Engineers, Inc. 1985 Design Report for Minkler Boulevard from Andover Park West to Southcenter Parkway, January 28, 1985. Bell- Walker Engineers, Inc. 1985 Central Business District Sidewalk Plan, April 12, 1985. Centrac Associates, Inc. 1985 Final Location and Feasibility Study and Regional Travel Impacts Report for the South 188th Connector, January 1985. City of Tukwila Department of Public Works 1986 Draft Environmental. Impact Statement for the Minkler Boulevard Extension, March 24, 1986. .1982 City of Tukwila Comprehensive Land Use Policy Plan Collins, Brad 1985 Planning Director, City of Tukwila. Personal Communication, December 16, 1985. Entranco Engineers, Inc. 1985 Traffic Impact Study, Lot 1 - Spring Ridge Short Plat. Fehruary 14, 1985. 1986 Design Report, South 168th Street. September, 1986. Umetsu, Vernon 1986 Associate Planner, City of Tukwila. Personal Communication, September 10, 1986. 101 DISTRIBUTION LIST Allied Stores 633 Southcenter Mall Tukwila, Washington 98188 Andover & Associates 854 East Mercer Way Mercer Island, Washington 98040 Attn: Mr. Thomas Yedor Audubon Society Room 619 - Joshua Green Building Seattle, Washington 98101 Attn: Dyanne Sheldon Bon Marche c/o L. V. Miller 3rd & Pine Seattle, Washington 98111 Bon Marche Distribution Center 17000 Southcenter Parkway Tukwila, Washington 98188 Attn: Mr. William Hicks Buck & Gordon 1011 Western Avenue Seattle, Washington 98104 Attn: Mr. Jay P. Derr Chamber of Commerce 950 Andover Park East Tukwila, Washington 98188 Attn: Mr. Terry Anderson Chevron USA, Inc. P.O. Box 7611 San Francisco, California 94120 Chevron USA 220 Strander Boulevard Tukwila, Washington 98188 City of Kent Public Works Department P.O. Box 310 Kent, Washington 98031 Attn: Mr. Don Wickstrom, Director City of Renton Public Works Department 200 Mill Avenue,South Renton, Washington 98055 Attn: Mr. Dick Houghton, Director City of Tukwila Mayor 6200 Southcenter Boulevard Tukwila, Washington 98188 Attn: Mr. Gary L. Van Dusen City of Tukwila City Clerk 6200 Southcenter Boulevard Tukwila, Washington 98188 Attn: Ms. Maxine Anderson City of Tukwila City Council 6200 Southcenter Boulevard Tukwila, Washington 98188 Attn: Ms. Wendy A. Morgan, Chair City of Tukwila City Council 6200 Southcenter Boulevard Tukwila, Washington 98188 Attn: Mr. Edgar D. Bauch City of Tukwila City Council 6200 Southcenter Boulevard Tukwila, Washington 98188 Attn: Mr. Joe H. Duffle City of Tukwila City Council 6200 Southcenter Boulevard Tukwila, Washington 98188 Attn: Ms. Mahel J. Harris City of Tukwila City Council 6200 Southcenter Boulevard Tukwila, Washington 98188 Attn: Mr. Charles E. Simpson City of Tukwila City Council 6200 Southcenter Boulevard Tukwila, Washington 98188 Attn': Ms. Marilyn G. Stoknes City of Tukwila City Council 6200 Southcenter Boulevard Tukwila, Washington 98188 Attn: Mr. James J. McKenna Collins & Associats Suite 600, Merrill Place 411 First Avenue South Seattle, Washington 98104 Attn: Mr. Brad Collins Commercial Design Associates 4230 - 198th Street S.W. Lynnwood, Washington 98036 Attn: Mr. Scott Shanks Davis Wright Todd Riese & Jones 110 - 110th Avenue N.E., #700 Bellevue, Washington 98004 Attn: Ms. Linda M. Youngs Delco Group 2219 Second Avenue Seattle, Washington 98121 Attn: Mr. Peter Orser Doubletree Plaza 1600 Southcenter Parkway Tukwila, Washington 98188 Attn: Mr. George J. Neumann Doubletree Inc. 6225 North 24th Street, #200 Phoenix, Arizona 85016 Attn: Mr. James R. Smith Firestone 215 Andover Park West Tukwila, Washington 98188 Attn: Mr. Dennis McGriff Mr. Larry Hanson Firestone Zone Marking Office P.O. Box 68907 Seattle, Washington 98168 Attn: Mr. Russ Paris 104 First Western Development 4230 - 198th Street Lynnwood, Washington 98036 Attn: Mr. Mike Hess Foster, Pepper & Riviera 1111 Third Avenue Seattle, Washington 98101 Attn: Mr. John C. McCullough, Jr. Hayden Island Corporation 909 North Tomahawk Island Drive Portland, Oregon 97217 J. C. Penney Company Regional Tax Office #4015 Buena Park, California 90624 King County Surface Water Management Division Room 976 King County Administration Building Seattle, Washington 98104 Attn: Mr. Joe Simmler, Manager King County Traffic & Planning Division 9th Floor King County Administration Building Seattle, Washington 98104 Attn: Mr. John Logan, Manager King County Department of Planning 811 Alaska Building 618 - 2nd Avenue Seattle, Washington 98104 Attn: Environmental Coordinator MacAulay Nicolls Maitland International SeaFirst 5th Avenue Plaza Suite 3900 Seattle, Washington 98124 Attn: Mr. Frank J. Agostino Metro 821 Second Avenue Seattle, Washington 98104 Attn: Mr. Dick Sandaas Metro Environmental Planning Division 821 Second Avenue South . Seattle, Washington 98104 Matt Mikami 16813 Southcenter Parkway Seattle, Washington 98188 Office of. Archaeology and Historic Preservation 111 West 21st Avenue, KL -11 Olympia, Washington 98504 Attn: Mr. Robert G.•Whitlam Puget Sound Air Pollution Control Agency P.O. Box 9863 Seattle, Washington 98109 Attn: Mr. Arthur Dammkoehler Puget Sound Council of Governments 216 First Avenue South Seattle, Washington 98104 Attn: Mr. Jim Williams Puget Sound Power and Light 620 South Grady Way Renton, Washington 98055 Attn: Mr. Wayne Harris Rainier National Bank Controllers Department 086 P.O. Box 3966 T14 -1 Seattle, Washington 98124 Real Property West 44 Montomery Street, #4230 San Francisco, California 94104 Rosse Inc. c/o Samuel & Hazel Rosse 808 Howell Street Seattle, Washington 98010 M.A. Segale, Inc. P.O. Box 88050 Tukwila, Washington 98188 Shidler McBroom & Gates 3500 First Interstate Center Seattle, Washington 98104 Attn: Mr. Gary D. Huff Shidler, McBroom, Gates & Lucas Suite 505, Honeywell Center 600 - 108th Avenue N.E. Bellevue, Washington 98004 Attn: Mr. Dennis J. McLerran 105 Special Products Company P.O. Box 66314 Seattle, Washington 98166 Attn: Mr. Scott A. Salzer Springri,dge Investment, Inc. c/o Jones & Grey & Bayley, P.S. 36th Floor One Union Square Seattle, Washington 98101 Springridge Investment Ltd. 102.1 Island Road Victoria, British Columbia V8S 2V2 Canada Attn: Mr. Bruce Smith Stepan & Associates, Inc. 33505 - 13th Place South Federal Way, Washington 98335 Attn: Mr. Kent Stepan Trammell Crow Company P.O. Box 80326 Seattle, Washington 98108 Attn: Mr. Don Jefferson, Project Manager T.C.W. Realty Holding Company 400 South Hope Street Los Angeles, California 90071 'Union Pacific Corporation Tax Office P.O. Box 2500 Broomfield, Colorado 80020. Union Pacific Railroad 1515 Building S.W. Fifth Avenue _ Portland, Oregon 97201 Attn: Mr. A.L. Shoener, General Manager Union Pacific System 1015 Andover Park West Tukwila, Washington 98188 Attn: Mr. Craig Schuler Upland Drive Business Park 8815 - 38th Avenue N.E. Seattle, Washington 98115 U.S. Army Corps of Engineers Seattle District Environmental Resource Section P.O. Box C -3755 Seattle, Washington 98124 U.S. Department of HUD Valuation Department 1321 Second Avenue Seattle, Washington 98101 U.S. Department of Interior Bureau of Land Management Regional Office East 4217 Main Street Spokane, Washington 99202 U.S. Postal Service Tukwila Branch 225 Andover Park West Tukwila, Washington 98188 Washington State Department of Game Program Manager Environmental Affairs Team 600 North Capitol Way Olympia, Washington 98504 Washington State Department of Ecology Mail Stop PV -11 Olympia, Washington 98504 Washington State Department of Transportation District Design /Engineer/ Environmental Review 9611 S.E. 36th Street Mercer Island, Washington 98040 Washington State Department of Transportation 6431 Corson Avenue South Seattle, Washington 98104 Attn: Mr. Jerry Schutz Planning and Research Coord Washington State Office of the Attorney General Dexter Horton Building Seattle, Washington 98104 106 APPENDICES Appendix A SCOPING COMMENTS SCOPING COMMENTS Davis, Wright, Tood, Riese and Jones Hayden Corporation King County Department of Planning and Community Development Metro Macaulay Nicolls Maitland International Seattle Audubon Society Shidler McBroom Gates and Lucas The Transpo Group Scott Salzer Union Pacific Railroad Company U.S. Army Corps of Engineers, Seattle District DAVIS. WRIGHT. TODD. RIESE & JONES • PAR r WCLUOWO PROFESSIONAL COR0O6•TIONS 110 110TH AVENUE NE. SUITE 700 BELLEVUE. WASHINGTON 96004 12081 45145686 T ELE C O RE R: 12061 451 .6161 December 2, 1985 Transportation Committee City Council City of Tukwila ' 6200 Southcenter Blvd. Tukwila, Washington 98188 Re: Extension of South 168th Street 4200 SE•TTIe'FM6T N•lgNLL SANS OUROO,G SEATTLE. WASHINGTON 68154 ROOT 622.3150 )2601• TELECOM,120411•22.•322 55o west so. MI.uE 2 SUITE 50 ANCHORAGE. ALASKA 66501 Icon Hawes TELECOFKR: 1607. 216.1161 1151 N STREET N W. SUITE 600 WASHINGTON. 0 C. 20036 12021 6221175 TELECOPER: 202) 266.3166 KE•6E REPLY TO BELLEVUE OFFICE Dear City Council Members: We have been informed that the Transportation Committee will be meeting December 3, 1985 to hear concerns of various property owners on the proposed extension of South 168th Street between Southcenter Parkway and Andover Park West. We represent TCW Realty Advisors which owns property on the south side of the proposed street extension and fronting on Andover Park West. Based upon the information provided at the briefing by Entranco Engineers on November 20, 1985, we would like to express cautious support for the extension of the street. There are some areas of concern, however. The present design proposes to take 30 feet of right -of -way from the properties to the north and south of the roadway. The TCW Realty Advisors' property is encumbered on the north by a railroad spur and an underground electrical transmission line. The present design would require relocation of both of these improvements at sub- stantial cost to the City. We recommend that the street be located to the north of the existing TCW property line placing it entirely on undeveloped property. This location would eliminate the cost of relocating the railway line and utility line and will reduce land acquisition costs. We are concerned that if the railway line is relocated, it will be relocated farther to the south and will result in a substantially greater taking of TCW Realty Advisors' property than presently proposed. Our client's property is developed and any taking will be costly and will create a hardship. Transportation Committee City Council City of Tukwila December 2, 1985 Page 2 We ask that the location of the street and the land acqui- sition costs and utility and railroad relocation costs be clearly; analyzed in the Environmental Impact Statement. Please also consider this letter to constitute a comment on the Scope of EIS. If you have any further questions, please do not hesitate to contact me or Thomas Herta at TCW Realty Advisors, 400 South Hope Street, Los Angeles, California, 90071 -2899. Very truly yours, DAVIS, WRIGHT, TODD, RIESE & JONES v �z.yLChf- Linda M. Youngf LMY /kg cc: Mr. Thomas Herta Mr. Brad Collins, Planning Director Hall Baetz, Esq. . HAYDEN CORPORATION December 2, 1985 FEDERAL EXPRESS Mr. Phillip Fraser Senior Engineer City of Tukwila 6200 Southcenter Blvd. Tukwila, Washington 98188 RE: Proposed 168th Street Development Impact upon Parkway Square Shopping Center Dear Mr. Fraser: 900 N. TOMAHAWK ISLAND DRIVE PORTLAND. OREGON 97217 PHONE (503) 283-4111 The purpose of this letter is to formally establish the concerns of property owner, Real Property West, Inc., for the proposed development of 168th Street between Andover Park West and Southcenter Parkway. As outlined in the November 20, 1985, meeting with Entranco Engineering and the City of Tukwila Engineering Department, a feasibility study is now being prepared to be presented to the City of Tukwila Transportation Committee on the development of 168th Street. At that time, Hayden. Corporation, representing Real Property West, Inc., expressed several key concerns and their possible adverse affect to the property known as Parkway Square Shopping Center. As now appropriate, I will restate these concerns by the property owner: 1. Loss of Service Driveway: The Sanitation and building service areas are now designated in the south property line boundary of the shopping center. This access is essential to the daily operations and management of the shopping center and would be eliminated with the proposed roadway. 2. Building Setback: The roadway proposal would create a ten (10) foot setback from the sidewalk curb to the building wall. Tenants and customers would not have adequate access area for efficient retail use. 3. Grade Variation: The roadway proposal creates a three (3) to four (4) foot grade level variation between the roadway /sidewalk (lower) and building level (higher). This would result in severe access, design and foundation problems. 4. Public Identification & Physical Barrier: As a retail location it is essential that street traffic identify and obtain easy access to the shopping center. The proposed roadway would create a traffic problem and potential hazard for left turn access from Southcenter Parkway and in addition produce a visual and physical barrier from the proposed roadway. Mr. Phillip Fraser December 2, 1985 Page 2 5. Project Cost and Construction: The considerable cost of development of a roadway cannot be absorbed in any proportion by the property owner. Given existing ecomonic conditions any construction interference with the daily operation of the shopping center tenants is unacceptable. It is the conclusion of Real Property West, Inc., that the present proposed 168th Street Development would have a major negative impact on Parkway Square Shopping Center. Real Property West proposes the feasibility study by Entranco Engineers for the City of Tukwila Transportation Department be terminated before an additional and unnecessary expenditure of additional public funds. Best regards, Larry W. Summerton Contract Property Manager for Real Property West, Inc. LWS:nin M39D11 cc: Real Property West, Inc. — — — — • — • — — — — — — — • — — • King County Executive Handy aevelle Department of Planning and Community Development (lolly Miller. Director December 17, 1985 Mr. Brad Collins Planning Director City of Tukwila 6200 Southcenter Boulevard Tukwila, WA 98188 RE: Scoping Notice for South 168th Street Dear Mr. Collins: The Department of Planning and Community Development has reviewed the above scoping notice and concurs with the City of Tukwila's Determination of Significance. We believe the Environmental Impact Statement (EIS) should cover the following concerns. Environmental and Resource Issues Tukwila Pond is noted as a valuable stopover for migrating waterfowl. The pond is used throughout the year by a large number of diverse waterfowl species. It provides critical habitat for resident and migratory waterfowl. While portions of the pond have been affected by human actions in the past, the southern portion (currently proposed for fill) is presently the least disturbed area and has the highest diversity of vegetation. This is the portion of the site that would be destroyed by the development proposal. We believe the potential for "enhancement" on the rest of the site is not justification for eliminating an area that is already stable and providing excellent and rare habitat. If possible, Tukwila Pond should remain undisturbed. The EIS should also address what, if any, long -term management plans exist or are under development for Tukwila Pond. Transportation Issues The EIS should identify the need for the project, consistency with local plans, alternative alignments considered, and the future function of the new road. 811 Alaska Building 618 Second Avenue Seattle, Washington 98104 12061 344-7303 Mr. Brad Collins December 17, 1985 Page Two Any impacts to King County roads as a result of this project should also be addressed. Traffic volumes and distribution should be discussed on roadways which would experience a significant change from existing traffic patterns. Should you have any questions concerning these comments, please call Bill Hoffman at 587 -4693. Sincerely, HOLL MILLER Director HM:LG:ds TPLG37 cc: Ralph Colby, Supervisor, Plan Implementation, Building and Land Development Division ATTN: Dyanne Sheldon, Environmental Planner Lou Haff; County Road Engineer Harold Robertson, Manager, Planning Division ATTN: Bill Jolly, Chief, Resource Planning Section David Masters, Resource Planner Bill Hoffman, Chief, Transportation Planning Section David Mark, Transportation Planner Lisa Grote, Transportation Planning Assistant Lois Schwennesen, Chief, Community Planning Section 4i:1T1ETR® Municipality of Metropolitan Seattle Exchange Bldg. • 821 Second Ave., Seattle, Washington 98104 December 13, 1985 Bradley J. Collins, Planning Director City of Tukwila Planning Department 6200 Southcenter Blvd. Tukwila, Washington 98188 Determination of Significance EPIC - 294 -75: South 168th Street Dear Mr. Collins: Metro staff has reviewed this proposal and offers the following comments. Water Quality Metro anticipates no significant adverse impacts to wastewater facilities. We anticipate no significant degradation of surface water quality provided all mitigating measures both during and after construction are implemented in a timely manner. The proposal includes fill in Tukwila Pond and adjacent wetlands. Metro recognizes wetlands as environmentally sensitive areas with unique characteristics for wildlife habitat and water quality protection. Wetlands, such as Tukwila Pond, are important ecological systems which can improve water quality in varying degrees by temporarily or permanently retaining suspended materials, excess nutrients, toxic chemicals and disease - causing micro - organisms. Additionally, Tukwila Pond may now function as a migratory route for waterfowl. Potential adverse impacts on the water quality of the pond and adjacent wetlands caused by the proposal can be expected to impact wildlife habitat. In 1983, Metro evaluated the Tukwila Pond area as a possible site for the Tukwila Transit Center. After an in -depth analysis of the site which included a wetlands inventory report by a consulting wildlife biologist, Metro eliminated the site from further consideration. Metro's investigation and the wetlands report found, among other things, that : Bradley J. Collins December 13, 1985 Page Two 1. Any development within the Tukwila Pond area would adversely affect wildlife and result in a reduction in both the numbers of individuals and diversity of wildlife species; 2. If development does occur, the least impact on wildlife would occur from projects focusing on the northern boundary of the site; 3. Increased runoff from additional impervious surface should be directed away from the pond to prevent degradation of water quality. Because of the value of the wetland habitat and Metro's other activities aimed at protecting water resources, Metro rejected the pond area as a site for the Tukwila Transit Center. Metro acknowledges that King County has included wetlands in its Sensitive Areas Program. While recognizing that the proposed project is within the corporate limits of the City of Tukwila, we encourage the proponent to consider the Sensitive Areas Program guidelines and mitigating measures to avoid adverse impacts which may arise from the construction and implementation of the proposed project in Tukwila Pond and adjacent wetlands. In addition, Metro recommends that any construction activity related to the project be prohibited in Tukwila Pond and adjacent wetlands unless no other feasible, less environmentally - damaging alternative exists and that a buffer zone between the proposed project and the wetland be established. Metro recommends that this zone extend at least 50 feet away from the wetlands boundary. Should the proponent find that no other feasible, less environmentally - damaging alternative exist, measures to prevent any degradation of water quality should be taken. These measures should include, but not be limited to: o use of sediment curtains or containment fabrics to prevent sedimentation into the pond; o identification of runoff discharge points into surface waters through King County's drainage planning process; o methods to prevent toxic materials, petro - chemicals and other pollutants from entering surface water during and after construction; o provisions for maintaining adequate setbacks and wetland vegetation; o revegetation of affected areas. •= Bradley J. Collins December 13, 1985 Page Three Public Transportation Pedestrian access and the pedestrian environment are concerns of Metro since they affect the ability of potential transit riders to get to and from bus zones. The environmental impact statement should include a discussion of pedestrian access amenities. Another factor which affects transit_and transit ridership is the type of development associated with the proposed access road. What other types of development are planned in and adjacent to the Tukwila Pond? Also, does the proponent envision any additional roadways or traffic control measures for the area which may affect public transportation? The EIS should also specify the extent and degree of traffic impacts in the area which may arise from the proposed project. Thank you for the opportunity to review and comment. Very truly yours, Gregory M. Bush, Manager Environmental Planning Division GMB:dww MACAULAY NICOILS MAITLAND INTERNATIONAL Real srare Broker.. Cunsuhanis. Manager f.rabli.he, 1898 .nMxr Wahl. Mr. Brad Collins Director, Planning Department City of Tukwila 6200 Southcenter Blvd Tukwila, WA 98188 Dear Brad: COLLI ERS Irur rnn.xral Prnlw I Cnnwhu +r. December 9, 1985 It has been requested of me by the owners to relate the desires and opinions that the Spring Ridge property be viewed as a developmental site and not merely vacant land in reference to the addition of 16eth Street. Although Spring Ridge does not have buildings and other obvious physical obstructions, it would appear very apparent that the Spring Ridge property is available to solve any•proble m. Unfortunately, said . property has enough problems at this time and- further restrictions, conditions, setbacks, and encumberances that would force building development further into lower site coverages will further endanger the development of said site. We certainly appreciate the opportunity to voice the concerns of the owners, as well as your concerned understanding of the overall scope in regard to the City. Respectfully yours, MACAULAY NICOLLS MAITLAND I ATIONAL FJA :jg cc: Bruce Smith Suite 3900 Sea(irst Filth Avenue Plaza. 800 Fifth Avenue. Seattle. WA 98104 Telephone (206) 223 -0866 '..nrk• V.....xnr. (.ak;n. lanxxnnn 1rr.x.ka Ilnnx4 tinlla,x x.• Alala.va Ikxrrl Arrng .SIwau l nnr.l knrgrkrrn 1',1114,1 SW, O3eattle 2ludubcn Otocietp December 12, 1985 Washington Nonpndit Corporation 619 Joshua Green Building • Seattle. WA 48101 • 206t622b695 Mr. Brad Collins Planning Director, City of Tukwila 6200 Southcenter Boulevard Tukwila, WA 98188 Re: Tukwila Pond; File: EPIC 294 -75 Dear Mr. Collins: Seattle Audubon Society has received notice of the declaration of significance for the proposal to construct south 168th St. accross the south end of Tukwila Pond. We agree with the determination of significance and request that we become a party of record for this project. In addition to those items listed in the narrative of the scoping notice we would request that a detailed study be conducted on the aspect of habitat provided by this pond in its current condition. How does the pond function in the environmental system comprised of the openspace associated with the freeway right -of- way, Tukwila Pond, and the Green River, especially relating to resident and migratory birds. Industrial, commercial, and multifamily developments have maximized land use in the Tukwila area and the open waters of Tukwila Pond, the associated wetland vegetation, and the open space surrounding it provide excellent habitat in stark contrast to the surrounding land use. The southern margin of the pond contains the highest diversity of wetland vegetation and it is the area least impacted by human intrusions; for these reasons it receives the highest use by wildlife, especially more reclusive waterfowl species. The placement of the road alignment in this area would destroy the most intricate aspect of this wetland system. Enhancement of wetlands is a possibility in certain situations, however it is not a desirable or ethical attitude to assume that destruction of the most productive area of this wetland could be justified by an enhancement proposal on the remains of the wetland. The question arises as to the intent of such a road alignment: what property is proposed to be accessed which could not be accessed with existing thoroughfares? Could not the parcel to the west of the pond be accessed with a cul -de -sac from Southcenter Parkway? This should be considered as an alternative to the proposal. page 2: Collins What are the long range plans of the City of Tukwila for Tukwila Pond and its surrounding openspace? Will it continue to be submitted to repeated development proposals or will the City make an effort to preserve this wetland and a significant area of openspace surrounding it as a visual, biological, educational and open space amenity to the City of Tukwila? Seattle Audubon is opposed to the project as it is pre- liminarily proposed. We anticipate the opportunity to comment on the technical documents for this proposal, and if possible, to comment at public hearings which may be held in conjunction with the project. Thank you for this opportunity to comment on this proposal. DS: lws Sincerely, DyanrSe Sheldon, Conservation Chair • • • - - - - = - - - - - SH IDLER McBROOM GATES & LUCAS ATTORNEYS AT RAW • A PROFESSIONAL SERVICE CORPORATION Sunk v10 Eau Inarwrt l oner '.enik, M..kugI .. 4XI1.14 Ielepl.nc 01012:7 JNU iek..per 0101 e:_`-SIIII Ieka. !4, W dtl December 16, 1985 DENNIS 1. Mc1ERRAN &IknN OfTwe Hand Delivered Mr. Brad Collins, Planning Director City of Tukwila 6200 Southcenter Boulevard Tukwila, Washington 98188 Re Sopping Notice - South 168th Street EIS File No. EPIC 294-75 Dear Mr. Collins: &Alma 4IS H.c,.tll Cencr Nal MlAAn AK N E &Ikaue. W. h.nfun.A.lu Tckphn[ .20,11I!130,.1 Ick..p.er .1,1•11 J‘,4 VIM We represent The Bon with regard to their Distribution Center located at 17000 Southcenter Parkway in Tukwila. Our client has asked that we provide comments on the City's recently issued Scoping Notice for the South 168th Street Environmental Impact Statement. We would request that the Draft EIS for the proposal fully address the Issues and concerns identified below. I. LAND USE. A. Impacts on The Bon Distribution Carter. The Bon Distribution Center is a major facility which receives and ships the merchandise for all forty Bon stores located in the Western United States. The proposed South 168th Street project will have major impacts upon the existing use made by The Bon of its Distribution Center. The tentative plans presented by the City and its consultants would severely disrupt the operations of the Distribution Center and could even require its relocation. Because there is no right -of -way currently existing through the Distribution Center site, at least thirty feet of The Bon's property would have to be taken to accommodate the proposed street. The area which would be taken is currently developed with improvements essential to the proper functioning of the Distribution Center. A truck loading area, a rail spur, and refueling area with underground tanks and pumps would all be severely disrupted or eliminated by the proposed street. The northwestern access to the Distribution Center would also be eliminated. Mr. Brad Collins December 16, 1985 Page Two The most severe impact on the existing use would be disruption of truck loading on the north side of the building. All or substantially all of the existing property is necessary for trucks to back into the eighteen loading bays where Incoming merchandise is offloaded. The internal systems of the Distribution Center building have been designed in a manner which requires incoming goods_to_be unloaded on the north side of the building. A complex system of automated tracks and conveyors takes the incoming merchandise to central receiving and processing areas where the merchandise is repacked or separated for outbound shipment to retail stores from twenty loading docks on the south side of the building. The internal systems within the building are not easily or inexpensively modified. If loading on the northern side of the building is eliminated, there is insufficient space on the current property and inside the building to accommodate such a change in operations. All alternative loading areas around the building are already dedicated to other essential operations. Rail unloading also occurs on the north side of the building. The proposed street would likely eliminate one of two rail spurs currently used by The Bon for offloading and car stacking. The two spurs are necessary at peak periods to allow greater numbers of rail cars to be unloaded. It is not likely that the spurs can be relocated and to do so would also disrupt the internal organization of the Distribution Center building. Elimination of the northern access would also be potentially disruptive to the retail operation conducted in the northwestern portion of the building, as customer parking is primarily accessed through the northern driveway. Truck traffic flow would also be disrupted, as The Bon currently routes inbound delivery trucks around the building in a clockwise manner and out the northern access. This clockwise flow allows monitoring of entry for security purposes and prevents overflows of trucks at the northern loading area. An open curb system for truck loading would eliminate the truck traffic control currently exercised by The Bon's security personnel. The cumulative impact of the problems created by construction of South 168th Street may be great enough that The Bon's current use of the property would have to be discontinued. It is quite certain that a substantial amount of damage would be caused to the existing land use and probably to other potential users of the existing building. These impacts should be fully identified and explored in the EIS. B. impacts on Other Land Uses. Several other properties and uses could be substantially affected by the proposal. The shopping center located just north of The Bon Distribution Center owned by Real Properties West would suffer several major impacts. The users located in the center have their merchandise loading and service doors on the south side of the building. Construction of a street would eliminate the existing access drive serving the loading doors. Trucks serving these shops would have to park on the street if South 168th is constructed. Garbage Mr. Brad Collins December 16, 1985 Page Three loading areas would also be affected. Additionally, because of a grade differential problem, the loading and service doors would probably be three to five feet higher than the street grade. This would create further difficulties with use of the existing doors. The TCW Realty Advisor's property located directly east of The Bon Distribution Center contains Boeing Computer Service offices. One of the alternatives discussed by City consultants has been relocation of the rail line located along the northern boundary of the TCW property to a location further south because of soils problems on the Tukwila Pond parcel. Movement of the rail line would eliminate existing parking for the offices located on the TCW property. The impact on available parking for the office use should be evaluated. Also, the EIS should address the impacts of the proposal on land uses planned for the Tukwila Pond parcel. At a minimum, a portion of the developable area of this property will be lost to street construction under the proposal. II. TRANSPORTATION. As discussed in the Land Use section above, the proposed street would have a number of impacts on existing transportation systems. The Bon's existing traffic flows would be disrupted by closing the northwest access to the property, by possible prevention of counterclockwise truck flows around The Bon Building and by disruption of truck loading. The railroad operations within the location of the proposed right -of -way could also be severely impacted. A letter from The Transpo Group is attached which identifies the nature of the proposal's impact upon The Bon's truck offloading operations. The letter also indicates that the truck loading operations cannot be moved and, therefore, would have a severe impact upon the functioning of the proposed roadway as well. These impacts should be fully explored in the EIS. Additionally, the existing railroad service is likely to be modified or lost due to the proposal. The exact nature of the proposal and any alternatives with respect to rail service should be presented in the EIS. The cost of relocation of rail facilities should also be fully identified. With respect to traffic analysis in the EIS in general, there is a need for a complete area traffic study to determine whether the proposed street is really necessary or will actually solve any perceived problems with traffic flow. Because the City is proceeding with other major improvements in the area such as Winkler Boulevard, any traffic study should consider whether other proposed traffic improvements will resolve problems with traffic flows on Strander Boulevard. Based upon discussions with various staff members, it is apparent that no area -wide traffic study has been done for a number of years. Without preparing such a study, the need for the proposed street cannot be fully explored. Mr. Brad Collins December 18, 1985 Page Pour As a general comment, the preliminary design and location of the proposed street need to be further defined before an adequate analysis of the environmental impacts can be prepared. In early meetings with the staff and design consultants, it has been apparent that many issues will remain unresolved until a proposal with more specific location and design features is presented. Also, prior plans prepared by the City have identified a north /south connection between Strander Boulevard and South 168th Street. The impacts of such a connector on The Bon's truckloading should be further explored in the EIS. If the north /south street would intersect In the area of The Bon's truckloading operations, there could be additional traffic concerns. If there is any possibility that such a link will be created in the future it should be discussed as the South 168th Street proposal is an essential preprequisite to such a link. M. UT LTITB.4. Puget Power has a 115 Kv. underground electrical vault and line located within the alignment of the proposed street. Puget Power has indicated that the line should not be placed within the actual roadway area and should be relocated. The costs of relocating the line should be identified, as well as the exact relocation alignment. Puget Power has tentatively estimated that relocation costs could be as much as half a million dollars. P1. EARTH. At early meetings, the staff and design consultants have identified a problem with unsuitable soils in the proposed road alignment. The extent of the problem should be defined In the EIS, and the specific construction measures which are proposed to deal with the problem should be stated. Also, the cost of special construction techniques necessary because of unsuitable soils should be identified. Any alignment adjustments made to deal with soils problems should also be identified. V. WATER, PLANTS, AND ANIMALS. Because the proposed street will occupy a portion of the Tukwila Pond site, a designated environmentally sensitive area, a full assessment of the impacts of the proposal with respect to wildlife usage of the pond and upon the pond in general should be made. VI. FINANCIAL IMPACTS. The proposal appears to be a potentially very expensive project and may even be cost prohibitive. Because of the need to acquire right -of -way, deal with unsuitable soils, relocate the existing 115 Kv. underground power line, relocate rail lines and possibly pay damages to users who will have existing uses disrupted, the City should make a good faith estimate of the range of costs involved in proceeding with the project and the alternatives. While the State Environmental Policy Act Guidelines discourage a cost/benefit analysis in an EIS, it will be highly desirable for decision- makers and the public to have reliable financial information available when decisions must be made on the project. Mr. Brad Collins December 16, 1985 Page Five Additionally, although the SEPA Guidelines do not require that the method of financing a project be investigated, it would be helpful If the types and sources of financing which could be used are identified. It is certain that this will be a major issue in later hearings. In preliminary discussions with staff, it has been indicated that an LID may be proposed for the project. The alternative financing methods which the City may use should be identified to allow full-consideration-of-financing 'options by -the public and the-ultimate decision - makers. - VII. ALTERNATIVES. The majority of surrounding property owners have expressed opposition to the project in early meetings. Certainly a discussion of the alternative of not building the street should be contained in the EIS. Also, since Tukwila is currently evaluating other east /west street improvements such as Minkler Boulevard, discussion of the alternative of building Minkler and /or other streets without South 168th Street should be evaluated. Alternative locations for the South 168th Street alignment should also be evaluated. An evaluation of whether the westerly end of the street can be relocated from between The Bon and Real Properties West sites to another location should be made. VIII. OBJECTIVES OF THE PROJECT. To clearly evaluate whether the objectives of the project will be met, a full area traffic study should be completed as part of the environmental analysis. The Bon questions whether there is a need for the proposed street if Minkler Boulevard is built and, therefore, questions whether the City's objective of lessening congestion on Strander Boulevard will be met. IX. CONCLUSION. The Bon invites the appropriate City officials and the consultants involved in the preliminary design study and EIS preparation for the project to take a tour of The Bon's affected facilities at an early date. The environmental impacts identified above can only be fully appreciated by viewing The Bon's operations. Please have the appropriate individual contact the undersigned to arrange a site tour. Additionally, please notify this office of any meetings or hearings and of the availability of any draft and final documents. Thank you for your anticipated consideration of the above. Very truly yours, SHIDLER MCBROOM GATES & LUCAS DJM /13-14 Attachment cc: Bill Hicks, The Bon Jim Maclsaac, The Transpo Group Transportation Planning & Traffic Engineering Consultants December 3, 1985 Mr. Dennis McLerran Shidler, McBroom, Gates & Lucas - 505-Honeywell-Center 600 108th Avenue NE Bellevue, WA 98004 SUBJECT: SOUTH 168TH STREET DEVELOPMENT PROPOSAL @romp DEC -319BS BARES & LOS Dear Mr. McLerran: We understand that the City of Tukwila is proposing to acquire right of way and construct a new 3 or 4 -lane street between Southcenter Parkway and Andover Park West. The new street would be located along the south edge of the "Tukwila Pond° property, and along the north edge of the Bon Marche northwest regional distribution facility property. There are a number of physical and environmental problems to be encountered by this proposed street alignment. I am confident that your brief will cover those issues. The purpose of this letter is to point out and discuss one major issue: • Impact of the proposed street on the Bon's north truck access and docking operations (or vice versa). Facility Access and Internal Function Mr. Bill Hicks was kind enough to give us an in -depth tour of the internal functions of the Bon warehousing and distribution facility. The internal processing is all engineered to receive incoming merchandise from vendors via 17 or 18 large truck docks plus rail docks along the north side of the building, and to ship out the regrouped and repackaged goods to 40 different store destinations via 28 truck docks on the south side of the building. The east face of the building is committed to truck docking for all furniture delivery operations in the Puget Sound area. As a result of this tour, we conclude the following: • There is no way to consolidate the north side truck docking facilities with those on the east and south building faces -- all three building faces have been developed to maximum internal functioning capacity. • Any attempt to relocate the north side truck docks would likely result in a need for major (if not total) reconstruction of the entire internal operations of the facility. The TRANSPO Group, Inc. • 23 -1481h Avenue SE, Bellevue, Washington 98007 • (206) 641 -3881 Ths TRANSPO G -ovp Mr. Dennis McLerran December 3, 1985 Page 2 • Hence, we view the north side truck docks and docking activity as an unchangeable given that the street project must be designed around. Receiving Dock Operations The large tractor /trailer rigs that deliver to the north side receiving docks require all of the space now available between the building face and the north property line. It would be impossible to maneuver the large rigs around parked rigs with loss of 30 feet of right of way (ROW) -- or any substantial portion thereof. In addition to truck maneuvering space, there is also need to °stack° incoming trucks while awaiting preceeding trucks to dock and undock. This stacking occurs along the north side of the rail spur line, and into the east side docking area. The dock access must be served by a counter - clockwise truck circulation pattern (westbound along the north building face). This is to orient the driver's view of the docking facilities as he backs into the dock. The facility manager was able to supply incoming truck counts for the months of October and November for the north side receiving docks. During October there were an average of 63 incoming trucks per day, or 126 docking and undocking movements per day. During November the averages were 54 and 108 respectively. The docking maneuvers generally occur between 7 AM and 4 PM. A docking maneuver can take from 2 to 4 minutes, depending upon the size of the truck and the number of trucks docked at the time. On occasion, a less experienced truck driver can take more than 5 minutes to dock. The undocking maneuver takes about one minute. In general only one docking or undocking movement can occur at a time. Given these statistics, and assuming 60 incoming trucks per day for purposes of easy calculation, incoming trucks currently use 3 x 60 = 180 minutes of docking time, plus 60 minutes of undocking time. This represents up to 4 hours of the 9 -hour operating day when all space along the north side of the facility is preempted by truck docking maneuvers. - Future Street Operations If a new public street is to utilize 30 feet of the north docking area, truck docking operations must of necessity utilize a portion of the public street. The street would have to be designed with no curb on its south side along the entire docking area. By paving the rail spur track area, it may be possible to provide incoming (westbound) truck access over the rail area south of the future public street ROW. However, when rail cars are present, truck ingress would have to circulate via the westbound lane(s) of the new street. No matter which way truck ingress occurs, the trucks must preempt the future street eastbound TRANSPO Mr. Dennis McLerran December 3, 1985 Page 3 lanes to make their docking maneuvers. Undocking maneuvers would need to penetrate both directions of travel on the proposed street. When rail cars are present, incoming trucks would also block a westbound lane of the street while awaiting for prior docking movements to be completed. In summary, if 30 feet were to be removed from the north docking area, the street design would need to provide unrestricted truck access across its south 'curbline'. Truck docking and undocking operations would block eastbound traffic operation on the street for up to 4 hours over a 9 -hour business day. Eastbound traffic flow would be subjected to one hour of delay time plus any delays associated with stacking of incoming trucks. Such delays would be intolerable to the general street traffic. The safety implications are quite apparent. Conclusions We do not believe that the existing north receiving dock operations of the Bon warehouse and distribution facility can co -exist with a new public street, if any significant portion of the docking zone is removed by the street. If trucks cannot penetrate the south half of the street in making docking maneuvers, the docking operations would be eliminated. Conversely, if the south half of the street were to be used during truck docking operations, street operation and safety would be unacceptable. We would strongly urge City staff and its consultant to observe the truck loading operations, and to tour the internal functions of the facility. We believe they would concur with our conclusions. Very truly yours, The TRANSPO Group, Inc. James W. MacIsaac, P.E. Principal Engineer cc: Bill Hicks • September 29, 1986 City of Tukwila Planning Dept. 6200 Southcenter Blvd. Tukwi -la -, WA- 98188 Attention: Mr. Jack Pace Re: Tukwila Pond Site Design Report S. 168th St. Dear Mr. Pace: FP 0 19861 1, 1 •,LA As an individual concerned with the "proper "" development of the Tukwila Pond site, I would like to make the following comments relative to the above referenced project. As in previous correspondence, I would like to point out that I am not a resident of Tukwila. In spite of this, I have spent considerable time at the pond since 1974 and have followed proposed uses and impacts with great interest. I have had the opportunity to briefly review the Design Report S. 168th St. and have the following comments. Recommendations were made as early as 1979 for cross streets in the "superblock ". This was at a time prior to slot of the extensive development that now exists. Before the superblock was completed, it seems that it would have been prudent to provide cross streets while the opportunity existed. This gross oversight shows a lack of planning for the ultimate use of the area. Vhile extensive development was allowed, little consideration was given to the results on traffic flow. Now to correct the problem, the S. 168th St. proposal toucbes'the most sensitive environment that has existed and does exist in the superblock. I would like to refer to a previous Draft BIS, dated Dec. 1979, "Tukwila Center - Chartwell Development Corp. ", page 50 para. 2, which states "The variety and productivity of the site are unmatched on any comparably sized site in the Green River Valley or greater Seattle area ". As I mentioned in 1980, this observation should not be taken lightly. Further comments on this will be reserved until the current Draft BIS is finalized. Admittedly I as not a traffic engineer, nor do I pretend to be, but I cannot see how this extension will solve or reduce the traffic problems in this superblock area. This is— particularly true since traffic lights are propsed at the intersections of S. 168th St. on Southcenter Parkway and Andover Park V.. Rather than two intersections at Strander Blvd. /Andover Park W. and Strander Blvd. /Southcenter Parkway subject to back -ups, there would now be four. This proposed project is not a safety related issue, as the design report states, but appears to be an attempt to say "we are trying to do something ". Also, this proposed extention does.nothing_for the - remainder of the superblock, which is the ultimate destination for most of the traffic. Further this project cannot be related to future development of the Tukwila Pond site, as there currently 1s no proposal being presented. In conclusion, to sacrifice 1/2 acre of an extremely sensitive and diverse system to provide a band -aid solution , does not seem to be in the best interest of the area. This proposal is to make up for the lack of planning and foresight on th part of the city planners. I do not feel that the extension will provide the relief for which it is intended and the City of Tukwila should consider other alternatives. Regards, Scott Salzef P. 0. Box 66314 Seattle, VA 98166 (206) 243 -4412 P. S. - Please include my name on the list for receipt of the final BIS cc: Mr. Joe Duffie President - Tukwila City Council REITH Y. BORAUN G..wmo JOHN F. WELSSER ■•••••■ G•yr Saar.. MA201.7507 UNION PACIFIC RAILROAD COMPANY LAW DEPARTMENT 1515 5 W Fd9■ A. Sumo 470 Por11 d. Organ 97701 -5495 13031219.7990 December 13, 1985 Mr. Brad Collins Planning Director City of Tukwila 6200 Southcenter,Blvd. Tukwila, Washington 98188 JEFF 5 ASAY G.N. .s w my as n.f ROY P FARWELL G...n.cnr., 1103. bro.nel CAROLYN L. LARSON I GANN, BARRY L GROCE ALL.N. Comma *Am SUM VI.1 Our File: 9208 -32 -2 Re: EPIC- 294 -75 - Proposed Construction of South 168th Street between Southcenter Parkway and Andover Park West Dear Mr. Collins: In response to your November 18, 1985 scoping notice, Union Pacific Railroad Company requests that the City include the following issues in its analysis of the environmental impact of constructing a new arterial street (South 168th Street) between Southcenter Parkway and Andover Park West. 1. Removal of the Northerly Spur Track Serving The Bon. If street construction necessitates removal of the northerly spur track, the EIS should address the impact on The Bon of cutting its car holding capacity in half and the resulting impact on the Railroad, e.g., increased switching time and costs and /or possible loss of business. In addition, the cost of removing the track should be included as a project cost. 2. Loss of Ability to Extend Lead Track. The spur tracks serving The Bon were aligned so as to leave room to the north for a future westerly extension of the Railroad's lead track. The EIS should consider the loss of rail service potential to properties north and west of The Bon and the need to compensate the Railroad for taking its right of way and damaging its remaining property. Mr. Brad Collins December 13, 1985 Page Two 3. Shifting Lead Track. If the street alignment . requires that the Railroad's lead track east of The Bon's switch be shifted to the south, the EIS should consider the following issues: (a) Right of Way Acquisition. If the lead track is shifted more than a few feet, it will not fit within the limits of the Railroad's existing easement, necessitating acquisition of additional right of way for the Railroad. (b) Design Limitations. Any realignment of trackage must meet railroad engineering standards. For example, the maximum allowable curvature for trackage is a curve with a radius of 459.27 feet. Where reversed curves are used, 100 feet of tangent (straight) track must be introduced between curves. Curves must end 50 feet before paralleling a building that is 8' 6" from the track centerline. Clearances between the track and the street or other structures must meet WUTC and Railroad requirements. These factors must be taken into consideration when determining the location and amount of right of way needed to realign the lead track. (c) Cost of Shifting Track. The cost of shifting the lead track from the turnout east of Andover Park West to The Bon's trackage, including crossing work in Andover Park West, should be included as a project expense. When the Draft EIS is prepared, I request that you notify me of its availability for review. CLL:gh Very truly yours, Carolyn /L. Larson • - • • - • - - - - - • • - • • - • • Planning Branch DEPARTMENT OF THE ARMY SEATTLE DISTRICT. CORPS OF ENGINEERS P.O. BOX C•3755 SEATTLE. WASHINGTON 98124.2255 Bradley J. Collins, Director Department of Planning City of Tukwila 6200 Southcenter Boulevard Tukwila, Washington 98188 Dear Mr. Collins: 'iFf 1 2 T7 We have reviewed the determination of significance for the construction of the proposed new arterial, South 168th Street, Tukwila, Washington, with respect to the U.S. Army Corps of Engineers' areas of special expertise and jurisdiction by law as designated by the President's Council on Environmental Quality on December 21, 1984. In response to your request for comments on the scope of the environmental impact statement, we have the following comment. The placement of fill material in Tukwila Pond or in adjacent wetlands may require a Department of the Army permit in accordance with Section 404 of the Clean Water Act. Information about the permitting process can be obtained by contacting the Seattle District Regulatory Functions Branch at the above address, or by telephone (206) 764 -3495. Thank you for the opportunity to comment on this proposed project. Sincerely, Copy Furnished: George W. Ploudre. P.E. Acting Chief, Engineering Division Commander, North Pacific Division ATTN: NPDPL -ER DEPARTMENT OF THE ARMY SEATTLE DISTRICT. CORPS OF ENGINEERS P.O. BOX C -3755 SEATTLE. WASHINGTON 98114 -2255 OSIII.V TO Regulatory Branca JAN 7198E dradley J. Cvnies, IIirecto: Department o; Plannin ,; City cf Tul i a 6200 3o.tLcentcr Co.a evurd Tukwila, Washington 95188 Dear tlr. Collin:.: ill JAN -8 1986 EN- (RANCO ENGINEFRS Reference Ch._ Corps Of Engineers letter of L'.:cel:ber advising you that a Departuent cf Coe Army permit may Le required for the placement of fill materiel into 1ulzwila ?ond c.r in adjacent wetlands at Tukwila, Washington. We i,ave reviewed all available information about tic site art.: determined that the existing pond dad adjacent wetlands are not waters of the United States. A D.partment of the Army pnrnit will not be required for the discharge of dredged or fill material at this site. Nothing in th's letter should he eocstrced as excusing you from compliance with other existing Federal, state, and local statutes, ordinances, or regulat+_on s , hie':. m'.g. t affect this work. cc: Mr. Dale Anderson Entranco Engineers 1515 - 116th Avenue Northeast, Suite 200 Bellevue, Washington 98004 Sincerely, Barren E. Barite.' Chief, Regulatory Branea Mr. Rex VanWormer Independent Ecological Services 1514 Muirhead Olympia, Washington 98502 DEPARTMENT OF THE ARMY SEATTLE DISTRICT. CORPS OF ENGINEERS P.O. BOX C.3755 SEATTLE. WASHINGTON 981243255 MAR 2 19Sf Regulatory Branch Mr. Ralph C. Colby King County Building and Land Development Division 450 King County Administration Building 500 Fourth Avenue Seattle, Washington 98104 Reference: Tukwila Pond Dear Mr. Colby: This is in response to your letter of February 2, 1987, concerning the Corps of Engineers jurisdiction in Tukwila Pond at Tukwila, Washington. You requested that the Corps make a jurisdictional determination in light of a proposed development that would eliminate Tukwila Pond. In late 1986, the Corps of Engineers published new permit regulations which became effective January 12, 1987. These regulations provide clarification by the Environmental Protection Agency of the definition of eaters of the United States and now include waters: (1) which are or would be used as habitat by birds protected by Migratory Bird Treaties or (2) which are or would be used as habitat by other migratory birds which cross state lines. This clarification is significant because it expands the Corps Sectiob 404 jurisdiction. Tukwila Pond is now considered to be a water of the United States and subject to Department of the Army permit requirements under Section 404 of the Clean Water Act. Under Section 404, authorization is required for the discharge of dredged or fill material into waters of the United States, including wetlands. If you have any questions concerning this determination, please contact Mr. Jim Green, telephone (206) 754 -3495. Sincerely, • 1 ,'• Samuel K. Casne Chief, Environmental and Processing Section King County Building A Land Development Division Parks. Planning and Resources Depal nwnl 450 King County Administration aktg. S00 Fourth Avenue Seattle. Washington 98104 February 2, 1987 Mr. Mike Bowlus U. S. Army Corps of Engineers Post Office Box C -3755 Seattle, WA 98125 -2255 RE: Tukwila Pond: Jurisdiction, Dear Mr. Bowlus: Sly r t5 ' 1 Fs.; 1 -1967 This agency has recently received an EIS Scoping Notice for a project involving the potential elimination of Tukwila Pond in the City of Tukwila, Washington. The site is located immediately south of Strander Boulevard, between Southcenter Parkway and Andover Parkway. We would request that the Corps make a determination as to whether this waterbody is under your jurisdiction in light of the pending EIS and potential development of the site. Please contact Dyanne Sheldon at 344 -5287 if you have further questions. S Ralph C. Colby Interim Supervisor Technical Services Section RCC:DS:klc cc: Dyanne Sheldon, Environmental Planner Appendix B BIOLOGICAL EVALUATION OF TUKWILA POND BIOLOGICAL EVALUATION OF TUKWILA POND 168th Street Right -of -Way Corridor City of Tukwila Tukwila, Washington for Entranco Engineers, Inc. 5808 Lake Washington Roulevard N.E. Suite 200 Kirkland, Washington 98033 by Independent Ecological Services 1514 Muirhead Avenue Olympia, Washington 98502 TABLE OF CONTENTS* Page INTRODUCTION B -1 HISTORY B -1 PROJECT SITE DESCRIPTION B -2 WILDLIFE HABITAT VALUES B -9 PHOTOGRAPHS, B -29 * Note: Portions of this evaluation have been incorporated directly into t1he Plant and Animals Section of the EIS text. B -i LIST OF TABLES Table Page 1 Partial List of Plants Around Tukwila Pond R -3 2 Birds Identified on Tukwila Pond R -6 3 Mammals or Sign Sighted Around Tukwila Pond .R -8 4 HEP - Baseline Assessments B -12 5 Habitat Suitability Index B -14 INTROUIICTION The general project area lies within the Tukwila CIO, a highly urhanized area containing urban landscaping and animals. The major plant and animal area directly affected by the proposed project is the Tukwila Pond and associated land areas. Biological data were collected from November 1985 to June 1986 during a series of site visits and field evaluations. Information contained in studies completed for Spring Ridge Properties, reports by King County, and Audohon Society notes were also utilized. Wetland plant data were accumulated during spring and early summer to locate annual species. Wildlife studies were extended from the winter through early summer to identify seasonal use and use by migratory species. Biological data suggest that the Tukwila Pond site is a highly used waterfowl area which is integrated with the Green River to the east. These birds use it as a stop over resting area and long term wintering-and nesting ground. This site has not heen designated as a significant wetland habitat by any federal, state, or local agency with jurisdiction. HISTORY The proposed project site and pond were, at one time, a part of a larger lowland that was the west bank of the Green River flood plain. It was intermittently wet from high winter waters and was flooded during large, 10 to 100 year flood events. It probably appeared much like lands along the ! /alley Highway near Auburn. As development increased between the toe of the hill on the west and the Green River, the water table and surface waster flow patterns changed. Areas such as Tukwila Pond became the low settling areas for surface flows. Each development that required filling further tilted the flood elevation, causing areas that had historically flooded only at high flows to hecome the ponding area for water from even the smallest rains. The filling reduced storage capability around Tukwila Pond and it began to form its present configuration. Filling of the area north and west of the pond further confined water, forming the deeper pond. With the Army Corps of Engineers flood dike along the Green River it is impossible for surface runoff to enter the river except at pumping stations. When the river —is high, no water can he put into the river, causing back -up in runoff systems. This has contributed to the creation of the pond and wetlands that now exist. B -1 With the stabilization of the pond's size and shape, a riparian border formed around the pond. The previously mentioned filling created a new riparian horder along the north and west hanks of less wet- dependent trees. Increased winter water depths have caused a die -off of a stand of willow in the southwest corner of the pond, creating a series of small grassy islands with dead -wood snags. PROJECT SITE DESCRIPTION The proposed 168th Street connection hetween Andover Park West and Southcenter Parkway extends along the south border of the Tukwila Pond wetlands adjacent to and encompassing the existing railroad spur. Alternatives A, B, C, and D all encompass all of the tree and shrub cover along the railroad, the willow /alder stand in the southwest corner, and a portion of the reed canarygrass ,meadow. A small portion of the pond including the shallow mudflat area along the south bank, and the small pond in the southeast corner of the undeveloped area, will also be impacted by Alternatives A, R, C, and D. The overall lake and south wetland area is of concern to this project because of the direct and indirect impacts that will be created on hoth the habitat and the wildlife species utilizing the habitat. The area of impact consists of four habitat zones. Three are vegetative zones, the fourth is open water. They are: 1. True wetlands (as described by King County). 2. Riparian borders, both wetlands and uplands in vegetative character. 3. The open water pond. 4. Transitional vegetation, i.e., changing from uplands to wetlands. The variety and productivity of the proposed 168th Street project site is the highest per unit area of the pond property since it encompasses the wetlands, pond edge, tree canopy and the shallow islands in the southwest corner of the pond. Table 1 is a partial list of plants found in these vegetative zones. TABLE 1 Partial List of Plants Around Tukwila Pond Common Name TREES: Red alder Black cottonwood Black willow Paper birch SHRUBS: Willow Scott's broom Snowberry Dogwood Vine maple \TINES: Blackberry Deadly nightshade GRASSES, RUSHES AND OTHERS Soft rush Reed canarygrass Beggartick Smartweed Pond lily Bentgrass Thistle Tansy Teasel Buttercup Smooth hawksbeard Fireweed Water plantain Slough sedge Duckweed Pondweed Arrowhead Scientific Name Alnus rubra Populus tricocarpa Salix nigra Betula papyrifera Salix spp. Cystisus scoparius Symphoricarpos spp. Cornus stoloniferia Acer circinatum Rubus discolor Atropa belladonna Juncus effusus . Phalaris arundenacea Bidens amplissima Pologonum amphibium Nuphar luteum Agrostos palustris Circium arvense Tanacetum vulgare Dispacus sylvestris Ranunculus repens Crepis capillaris Epilobium augustifolium Alisma plantago - aquatica Carex abnupta Lemma trisulca Potamogeton sp. Sagittaria cuneata Habitat Values The uplands, transitional wetlands, wetlands and riparian borders function as uplands during the late spring, summer and early fall. The low grass /rush areas in the transition and upland areas supply seed and green vegetation to a variety of small passerine hirds, pheasants, quail and mammals. The riparian zone supplies cover, food and nesting for most of the same species. The tangle of blackberry /nightshade provides protection from predation for nesting and juvenile rearing. Trees are nesting habitat for a variety of small birds as well as perching and hunting stations for small raptors and kingfishers. Trees adjacent to or overhanging the water provide shade and protection from aerial hunters for juvenile ducks. Grassy edges provide nesting for mallards. During the summer, the canarygrass wetland provides cover and some seed for a variety of small hirds. Its dense growth limits the amount of use by small mammals other than mice, or as a nesting site for ground nesting birds. It does provide cover from aerial hunters for these species. In winter, the upland, transitional and part of the riparian border still act as uplands. The wetland has standing water or the ground is saturated most of the time. There is some use of the upper crown and small birds and ducks feed on the seed heads that fall down into the standing water. As the water recedes, organic material is carried hack into the pond. This provides food for small organisms that are the basic food source for insects and small fish which, in turn, supply food for birds and some mammals. This wetland habitat is similar in value to other wetlands in King County and western Washington. Wildlife Wildlife studies were conducted in October and November as part of another project identified for development within the property which includes Tukwila Pond and the 168th Street corridor. Data from Audubon notes, a wetlands evaluation conducted by Dyanne Sheldon of King County, and field studies completed for the 168th Street study in April, May and June 1986 were combined in this report. Because of its isolation from other open space by roads and other developments, the overall wildlife use on the site is less than would be expected for a similar site, if that site were in a more open, natural setting, and not surrounded by development. However, bird species' diversity and numbers are high. The major area where the species diversity and composition is low is that of mammals which normally hunt open spaces adjacent to streams, lakes, and /or wood lots and of larger predators that hunt wetlands and pond edges. There have been reports of mammal use; however, evaluation of shore hanks, exposed mudflats, trails, and other open areas where ,sign would he evident, have failed to reveal any large predatory mammal tracks. Also, there is no white - washing in the large trees, or owl or hawk casts at the bases of trees, which would he evident if large raptors were utilizing the area as a regular hunting site. Birds The major winter use of the Tukwila Pond open water area is by waterfowl.' Other winter uses of the trees, shrubs, and tall grass, and the 168th Street right -of -way corridor are made by a variety of. birds (Table 2). The size and shape of the pond lends itself to loafing and resting by flocks of wintering or migrating waterfowl. Ducks currently using the pond include canvasback, shovelers, green- winged teal, pintail, mallard, ruddy duck, redhead and common merganser. Shoveler, pintail and canvasback flocks ranged from 75 to 100 birds .each. All birds except canvasbacks concentrate in the southwest corner with a majority of the use of pintail and green-winged teal occurring in the dead tree area hetween the small islands and the pond bank. Data collected from other censuses shows a high use of the pond by early migrating pintail and teal. Spring and fall migration use includes a variety of migratory waterfowl and shorebirds using the water area, particularly if the mud hottom is exposed along the south bank of the pond. Summer use includes a variety of small birds, including shorebirds (see Table 2), that use the area either in early summer migration pass- through, or nest in the area. Mallards use the area for nesting and brood rearing. No broods were observed in 1985, but at least two broods were known to have been brought off in 1986. Great blue heron and bittern hunt the shallow shoreline in the summer; blue heron remain year - round. Double breasted cormorants were also observed using the area for feeding during the winter. Adult pheasants were found in the south wetland area adjacent to the pond during both summer and fall. Although both adult roosters and hens were .ohserved, there were no observations, and there have been no reports, of broods being successfully raised on the site. TABLE 2 Birds Identified on Tukwila Pond Common Name Horned grebe Double- crested cormorant Mallard Pintail American widgeon Shoveler Green - winged teal Redhead Canvasback Ruddy duck C. merganser Cinnamon teal Lesser scaup Bufflehead Ring - necked duck Gadwall Common goldeneye Kestral Red - tailed hawk Valley quail Ring- necked pheasant Great blue heron Green heron Bittern Coot, Killdeer Spotted sandpiper Solitary sandpiper Lesser yellow legs Long - billed dowitcher Common snipe Herring gull California gull Scientific Name Podiceps auritus Phalacrocorax auritus Anas platyrhynchos Anas acuta Mareca americana Spatula clypeata Anas carolinensis Aythya americana Aythya valisineria Oxyura janaicensis Mergus merganser Anas cyanoptera Aythya affinis Rucephala alheola Aythya collaris Anas stepera Rucephala clangula Falco sparverus Ruteo jamaicensis Laphortyx californicus Phasianus colchicus Ardea herodias Butorides virescens Botaurus lentiginosus Fulica americana Charadrius vociferus Acitis macularia Tringo solidaria Totanus flauipes Limnodromus scolopaceus Capella gallinago Larus argentatus Larus californicus Number Season Sited W 1 W 10 SSFW 50 FW 50 FW 25 FW 100 F 25 FW 2 FW 50 FW - 5 SFW 15 SS 2 -5 W 25 FW 40 FW 20 FW 20 FW 3 1 F 1 Sign 6 3 1 3 3 Common Name Belted kingfisher Flicker Barn swallow Yellow - green swallow Common crow B.C. chickadee Common bushtit R.R. nuthatch Winter wren Bewick's wren Robin Kinglet Starling Rufous -sided towhee Yellow throat Red - winged blackbird American goldfinch Oregon junco House finch G.C. sparrow Song sparrow TABLE 2 Birds Identified on Tukwila Pond (Continued) Scientific Name Megaceryle alcyon Calaptes cafer Hirundo rustica Tachycineta thalassinia Corvus brachyrhynchos Parus atricapillus Psaltriparus minimus Sitta canadensis Troglodytes troglodytes Thyromanes bewickii Turdus migratorius Regulus spp. Sturnus vulgaris Pipilo erythrophalmus Geothlypis trichas Agelaius phoneniceus Spinus tristis Junco.oreganus Carpodacus mexicanus Zonotrichia atricapalla Melospiza melodia Number Season Sited 1 2 20 25 50 4 4 2 20 10 2.5 3 5 4 20 25 2 2 10 A listing of "birds observed by Audohon Society members, King County biologist, and Independent Ecological Services is reported in Tahle 2. Mammals Mammal use is limited in its diversity because of the isolation from other habitats. Mammal activity was even more limited along the south shore of the pond in the vicinity of the 168th Street right -of -way, because of the density of the canarygrass, small size of the site, its proximity to the railroad track and parking area, and isolation from a larger tract of upland habitat. Meadow mouse and vole tracks and sign were seen along the west, north, and northeast parts of the transition and upland zones. Other small mammals may use the area, but the density of the vegetation in the summer and standing water and wet conditions in the winter made it difficult to identify sign. Eastern cottontail were seen in the transition zone along the north and west sides of the pond, including a dense alder thicket in the southwest corner of the 168th Street right -of -way. There are numerous well used . trails in this zone, indicating fairly heavy use. The area appears to be: good brush rabbit habitat hut none were observed. Mammals are listed in Table 3. Common Name Shrew Mole Deer mouse Cottontail TABLE 3 Mammals or Sign Sighted Around Tukwila Pond Scientific Name Number Sited Sorex spp. common Scapanus spp. uncommon Peromyscus maniculatus common Sylvilagus floridanus 10 -15 Fish, Reptiles and Amphihians The open water is fish habitat for at least two small unidentified species of fish that appear to he food for waterfowl and marsh birds. The edges on two sides of the pond are shallow and support vegetation that is a prime feeding and hiding area for small fish as well as being cover for red - legged frogs and other invertebrates. Herons, mergansers, kingfishers and cormorants have been observed feeding on the fish species in the pond. (The identification of the two species of fish is based on observations of mergansers feeding on a small slender fish typical of. trout, and a small rounder bodied fish more typical of sculpin.) Tree frogs use the area both for breeding and rearing of young. Garter snakes have heen seen in the slope bank under the blackberry adjacent to the crescent shaped pond in the southeast corner of the site and in the alder thicket area in the southwest corner. Unique Species Review of Washington State Department of Game and U.S. Fish and Wildlife Service documents, contact with personnel in the endangered species programs of both state and federal agencies, and a review of data and reports collected over the years by the Audobon Society indicate that there are no Endangered, Threatened or Sensitive plants or animals on the site. ' Migration Routes The site is within the Pacific Flyway, and as such is utilized by birds that normally migrate through the western Washington area in spring and 'fall. The pond is heavily used by both waterfowl and shorebirds. The - uplands and riparian border are used by goldfinches, siskins and other small birds. WILDLIFE HABITAT VALUES Procedures Two different procedures were used to determine the biological and functional values of the wetland area effected by the project and the adjacent pond and riparian horder. They were: B -9 1. Rest professional judgement hased on wetland systems and identified biological uses. 2. Habitat Evaluation Procedures (HEP), U.S. Fish and Wildlife Service. The area to be directly impacted was determined using the "Design Report" to locate the different road alignments. The biological values identified were those on the area to be filled and those of the adjacent area that would be secondarily impacted by construction and road and people activity. Riological Because of the density of vegetation and the lack of vegetative diversity, the south edge of the pond and wetlands up to the railroad fill have limited summer value to waterfowl and marsh birds, because of the density of vegetation and the lack of diversity. However, in winter months, when the grass area supports standing water, it does attract and supply food to waterfowl such as pintail, mallard and widgeon. The tree /shrub area abutting the railroad track, particularly in the southwest corner provides a valuable visual screen for the pond and provides islands of taller vegetation in the grass marsh forming a diversity of habitats and an "edge effect" wherever there is a distinct change in elevation or type of vegetation. The trees are nesting and loafing areas for a variety of passerine birds that feed on insects or seeds. The lake -pond edge creates another "edge effect" with the plant - mudflat -open water interaction. The vegetation varies from a dense willow tree stand along the north half to a cattail open grass area in the south third of the south pond hank. The dense tree edge provides a visual buffer for the pond, shelter from the wind, cover from predators, and nesting habitat for a number of species such as towhees, juncos, sparrows, and warblers. The seasonally exposed mudflat along the southern shoreline provides the required habitat for another distinct wildlife group. A variety of shorebirds such as solitary sandpipers, dowitchers and plovers wander over the mud and in the shallow water feeding on insects during the late summer and during fall migration. This area stays flooded during the winter and spring, then slowly becomes exposed in August and September as the migrating shorebirds return from the north. The flooded 'brush area in the southwest corner of the pond is an unusual habitat that provides excellent cover for a distinct group of species. 'In the winter, this area appears to provide the preferred cover of the mallard' ducks, shovelers and teal on the site. It is also the preferred perch site for juvenile swallow and kingfishers. This habitat is temporary in that it will change in five to ten years as the dead vegetation decays. The open pond appears to he changing, with a persistent vegetative intrusion of pondweeds and other submergent type plant species. This is an indication that the waters are getting shallower by the year. Throughout the seasons, the open pond site hosts a wide variety of wildlife species. The species occurring on the site change dramatically through the year due to changing site conditions and established migration patterns of shorebirds and ducks. In the fall the population increases and fluctuates as the migratory birds pass through. During winter, the site is dominated by permanent residents and ducks that winter in western Washington. Once again, in spring, migrating shorebirds, ducks and songbirds pass through, feeding heavily to support their continued flight south. Also in spring, nesting birds such as ducks, songbirds, pheasant and quail, that are established residents, construct nests and raise young. Some species, such as the song sparrow, pheasant, quail and several of the duck species, are year -round residents. Many species, such as the V savannah sparrow and the swallows, spend the spring and summer at the site then migrate south for the winter. The variety and productivity of the overall site are high for some species and marginal to low for others. This factor, combined with the close proximity to intensively developed adjacent land, makes this site unusual. It interacts with the Green River wetlands and waterway, offering escape and loafing habitat for a number of species, particularly waterfowl that fly between the two areas. The variety and productivity of the 168th Street corridor area is the highest per unit area of the pond as it, encompasses the wetlands, pond edge, tree canopy and the shallow islands in the southwest corner of the pond. Functional The wetland area to be filled for the road supports the following non - biological values: 1. It is a stormwater retention /detention area that expands during winter storms to encompass the entire south two- thirds of this portion of the undeveloped site. 2. Sedimentation /pollution control: The grass wetland and vegetated edge of the pond traps soil particulates, oils, etc., from road runoff. Reed canarygrass and cattail are two of the most effective biofiltering plants that grow in western Washington. With the exception of one drainage point, all of the water that runs into Tukwila Pond is filtered through grass - lined ditches or flat expanses of grasses. This area is in the southwest corner where the water runs in a ditch from parking lots to the pond. 3. "Habitat Assessment using Hahitat Units ", a portion of the Habitat Evaluation Procedures (HEP - Table 4), was used to create a numerical index for wildlife use only. This procedure was developed by the U.S. Fish and Wildlife Service for use in impact assessment and project planning. It is a means of assigning quantitative values to different Habitat Units (HU) depending on their use by selected fish or wildlife species. TABLE 4 Habitat Evaluation Procedures (HEP) Existing Conditions Cover Type Acres Project Area Project Site 1. Open Water 2. Riparian 3. Wetland 1. Open Water 2. Riparian 3. Wetland is.n 1.9 4.6 0.15 1.0 0.50 A complete HEP using Hahitat 'Suitability Indices models was not conducted because of the small size of the project site and limited hahitat types and wildlife species. HEP values (HSI) are identified for a site in its undeveloped condition. Each selected species and habitat type are then assigned a numerical value hased on professional judgement of one or more biologists. Impacts caused by a given project over a period of time are then evaluated and compared quantitatively. A formula that requires only target year values and an area estimate was used to calculate the values on this site. Verbal models, hased on known habitat needs and maximum use by selected species, were then developed and given a maximum value of 10.0. Total destruction of the habitat created a value of 0. The baseline values of the existing habitats and their comparison to the verbal models were assigned by the author (see Table 5). No baseline values of similar habitats in the general area have been conducted so there was no background data for comparison. Major habitats used were: (1) open water; (2) riparian; (3) transitional, i.e., changing to wetlands; and (4) wetlands, i.e., reed canarygrass. species selected were (1) waterfowl, general; (2) canvasback; (3) marsh birds; (4) passerine birds; (5) raptors; (6) srn;all mammals; .(7) predatory mammals. Raptors and predatory mammals are included to demonstrate limited values because of the isolation of the site from other habitats. Canvasbacks were isolated because of the concern placed on their management and survival by the U.S. Fish and Wildlife. Although redheads are in the same category, they were not separated as only two birds were seen on the pond. Build -out of the road right -of -way was assumed to be compelte in one year. The remaining pond was considered to he 19.0 acres. The model was also given a worst cast scenario created by Alternatives A, B, and C. The calculations demonstrate the area has a high value for wintering waterfowl (general) and canvasback, moderate value for small birds and marsh birds and low values for other species (Tables 4 and 5). HEP does not evaluate non - biological values such as hydrology or water quality. B -13 TABLE 5 Habitat Suitability Index* Project Area Habitat ** Wildlife Species 1 2 3 4 Average Waterfowl 9 5 4 5 4.6 Canvasback 8 1.6 Marsh Birds 6 5 5 2.2 Pheasants 6 5 5 3.6 Passerines 7 6 5 4.6 Raptors 2 4 2.0 Small Mammals 7 7 3 4.8 Predatory Mammals 1 1 n.6 Project Site Habitat ** Wildlife Species 1 2 3 Average Waterfowl 9 6 5 6.6 Canvasback 2 0.66 Marsh Birds 6 6 5 5.66 Pheasants 4 5 3.00 Passerines 3 8 5 5.33 Raptors 2 3 1.66 Small Mammals 5 3 2.66 Predatory Mammals 1 0.33 * 10 = maximum value; 0 = total destruction of habitat ** 1 = open water; 2 = riparian, 3 = transitional; 4 = wetlands Photographs Photo 1: Southwest corner of pond - drainage ditch flows east through stand of willow and alder. Photo 2: Cattail stand along south bank - looking NE; note willow behind cattail, length of pond. Photo 3: Reed canarygrass wetland along south side of pond. Area floods during winter. Good seed production for all birds. Pheasant habitat during summer. Photo 4: Willow how it drop. stand along south bank shields buildings even near east end. Note" during winter leaf Photo 5: Blackberry - willow stand along railroad. Photo 6: Small wetland at NE corner of project site. Smartweed and pond lily present. Good frog producing site; evidence of blue heron feeding. Photo 7: Northeast corner of pond. Good stands of cattail, smartweed. Vine is deadly nightshade which provides good nesting for numerous small birds and pheasant winter habitat. Photo 8: Overhanging willow in north end of pond provides. cover for ducks, hunting habitat for predators and nesting for small birds. Photo 9: Narrow riparian border along north side of pond. Combines blackberry, nightshade, willow, grass and occassional cottonwood trees. Denning and juvenile rearing habitat for rabbits, nesting for pheasants; buffer pond for waterfowl. Photo 10: Dead stand of alder /willow and small island in southwest corner of pond. Area heavily used by canvasback, pintail, green winged teal, shoveler and ruddy ducks, great blue heron and crows. Appendix C CITY OF TUKWILA CONDEMNATION PROCEDURES CITY OF TUKWILA CONDEMNATION PROCEDURES The following is a description of the general procedure for condemnation used by the City of Tukwila for projects not involving federal funds. It applies to all action alternatives (A, B, C and D). The City Council passes an ordinance authorizing the condemnation action to get the necessary right -of -way, i.e., the property necessary to construct the improvements. The ordinance states what the improvements would he and how it would be funded. The City Attorney then files a petition in the Superior Court in which the property is located, in this case King County, and asks the court to set compensation. At the same time, a hearing date before the court is set to determine whether the City is authorized to condemn the right -of -way. Ten days notice of the hearing is sent to each property owner who is served a petition. At the hearing, the court determines through testimony whether the property would be necessary for the proposed improvements and whether the City has the right to condemn it. A trial date is then set to determine the amount to he paid to each property owner. In King County, it can take three to six months to schedule this trial; however, cities can get priority over all cases except criminal cases. Therefore, the time frame could be reduced. The property owners are entitled to a trial before a jury unless it is agreed by the property owners to hold it before a judge. The City can obtain immediate use of the property prior to the jury trial. Possession can be within 15 days after the initial hearing and construction may begin immediately upon possession. If the owner does not give the property to the City within 15 days, then the owner forfeits the right to have his attorney's fees paid by the City. Prior to actual possession, the City must pay into the court the fair market value of the property based on the City's appraisal. These funds may then be drawn out by each respective property owner. Before the jury trial, the City can make a "30 -day offer" to the property owner. This represents the City's hest offer. At the jury trial, the jury decides the amount of compensation; if this is more than 10 percent greater than the "30 -day offer ", then the property owner is also awarded attorney's fees (assuming this has not been waived previously). The jury may look at the site even if construction has already started. If a partial acquisition occurs, which would he the case for each alternative and option in the proposed project, the determination of compensation could involve any of several methods. The fair market value of the entire parcel would be determined. Then the fair market value of the of the entire parcel would he determined. Then the fair market value of the part of the parcel which would be left after the acquisition would he determined. This second value is then suhtracted from the first to obtain the value of the taking. Several methods may be used to determine the fair market value, not all of which include establishing a value per square foot. For example, if the taking cones out of a parking lot or cuts off access to a property, then severance damages are awarded to the property owner since the damage to the entire parcel is greater than the actual loss per square foot. Market value may be determined by looking at comparable real estate sales, looking at loss of profit potential, and if loss of an improvement would occur as a result of the taking, looking at the replacement cost to build that improvement on another site.