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Home My WebLink AboutSEPA E97-0037 - RUHL PARR & ASSOCIATES - WENDY'S RESTAURANT BUILDINGWENDY'S RESTAURANT FAST FOOD RESTAURANT & DRIVE-THROUGH WINDOW 16200 WEST VALLEY HWY E97-0037 AFFIDAVIT 16G(2,(-1 Zet/a112_04- Li Notice of Public Hearing O Notice of Public Meeting O Board of Adjustment Agenda Packet O Board of Appeals Agenda Packet O Planning Commission Agenda Packet O Short Subdivision Agenda Packet O Notice of Application for Shoreline Management Permit 0 Shoreline Management Permit OF DISTRIBUTION hereby declare that: N]lermination of Non- significance 0 Mitigated Determination of Nonsignificance O Determination of Significance and Scoping Notice fl Notice of Action 0 Official Notice 0 Other []Other was mailed to each of the following addresses / 1 fmnia 71,11166,- Ec,locrj on 127)L-1-97 Name of Project I,Jof)r,() ) 4o7,wie6i,a Signature File Number E903'7 CITY OF TUKWILA DETERMINATION OF NONSIGNIFICANCE (DNS) DESCRIPTION OF PROPOSAL: CONSTRUCTION OF A 3.025 SO FT FAST FOOD RESTAURANT WITH A DRIVE-THROUGH WINDOW. PROPONENT: RUHL-PARR & ASSOCIATE LOCATION OF PROPOSAL, INCLUDING ADDRESS: PARCEL NO: SEC/TWN/RNG: 1 h20.0, WEST.3 V;AL'LE 064.5.80-00.8 • STREET ADDRESS': .ANY: LEAD AGENCY: :;y�;„CITY OF--:TUt,WILA; ?S FILE NO: 'E0-.0037 � The City h.as `de:termined`'thatM e sproposa,1 does not `hatve a.. Drobah,l e sionitican't"'adve'r-:e impact.o`n }the environment. An en•vironniental' impact statement (EIS) is riot recj,u.,iced under RCW 4.3.21c.03.0(2) (c) , This, deci_:ion'wa.v made atter revi;ee; of Ma:completed environmental c'heckl istand,,.other�' inforinatitinr•�on tile= with the lead agency; Thi infor•mati.on is avai lathe" tci''the 'ciubl icon• r1equest. :l•*-,l*;i•**:t•*t**k**.**-0.4`k*-*,kk*�**,**k*i�*.***;41,.****:k*******:l•.**•kkk.**:�:l•*' .****b•** � a -. k' \ ti... ,--2q1Tpi= detemincticn, istinatan•dsigned till's day Of EC, 44' Z L 1991. .. :,, , ' ,,, b t , ., a, Steve Lancia.ter; Respc ns. i o l e Off i c i& 1 4 City of Tuk.W4,1a, .(20631-3670 /0 6300 Southcen'ter 136(4.Jevard Tukwila, WA818e Copies of the p.r ci lures for SEPJA 4u.p;eal s' are ava i 1 ab l.e-:w•i th the Department of Comniun ,tv,_ Deve l opm:en.t :# :?. • City of Tukwila John W. Rants, Mayor Department of Community Development Steve Lancaster, Director MEMORANDUM TO: Steve Lancaster FROM: Michael Jenkins DATE: December 22, 1997 RE: E97-0037, Wendy's Restaurant Project Description: The proposal is to construct a 3,025 square foot Wendy's Restaurant at 16200 West Valley Highway. The proposal includes the building with a drive through window and a 42 space parking lot. Background: The project is located on the same parcel as a previously approved project for a BP gas station with a carwash at the same address. A determination of non- significance for the gas station and carwash was issued on March 12, 1997, under file E96-0035. Under W.A.C. and local codes, buildings less than 4,000 square feet do not trigger SEPA review. The only portion of this development that triggers SEPA review is the 42 on-site parking spaces. The applicant has submitted a Traffic Report related to on-site traffic impacts. The project must also comply with Tukwila's Concurrency ordinances concerning traffic (TMC 9.48) and sewer, water and storm drainage issues(TMC 14.36). A permit from WSDOT is required for access to the parcel from West Valley Highway. Approval by the Board of Architectural Review is required prior to the issuance of a Development Permit (TMC 18.60). Approval by the Director of Community Development is also required for applicant's request for shared parking with the BP station, under TMC 18.56. Recommendation: DNS 6300 Southcenter Boulevard Suite #100 • Tukwila, Washington 98188 • (206) 431-3670 • Fax (206) 431-3665 • City of Tukwila John W. Rants, Mayor Department of Community Development Steve Lancaster, Director December 16, 1997 Jim Anderson Ruhl-Parr and Associates 3625 - 132nd Ave S.E., Suite 100 Bellevue, WA 98006-1399 Re: Wendy's, 1620dWest Valley Hwy. (L97-0074 / E97-0037) Dear Mr. Anderson: To confirm our recent conversation regarding this case, we are looking to stay on schedule for a January 22, 1998 hearing before the Board of Architectural Review (BAR). To ensure this date is maintained, the issues concerning on-site circulation, shared parking and improved design solutions that we discussed should be addressed before December 29, 1997. To address the issues outlined above, we would appreciate solutions presented in a schematic format. By reviewing your solutions in this manner, we can discuss the issues and your solutions prior to committing to final plans. Please contact me as soon as possible if you can not submit schematics by December 29, 1997. I understand that Michael discussed the shared parking approval process with you. This request is a Type 2 decision under TMC 18.104. I have enclosed a copy of the Parking Code section that addresses the application materials needed for this review. The request may be made, with supporting documentation, in a letter format. I would like this process to be completed prior to the BAR hearing, so your application materials should be submitted as soon as possible. Sincerely, ck Pace Planning Manager c:\msoffice...97letter\9774issu.doc 6300 Southcenter Boulevard, Suite 11100 0 Tukwila, Washington 98188 s (206) 431-3670 0 Fax (206) 431-3665 • TITLE 18 — ZONING Loading Space Requirements Square Feet of Gross Floor Area (Except Basement Area) Number of Spaces Office Buildings, Hotels, Hospitals, and Institutions 1 • 1 3,000 , to 100,000 3 2 100,000 to 335,000 155,000 3 335,000 to 625,000 235,000 to 4 625,000 to 945,000 8 5 945,000 to 1,300,000 655,000 6 1,300,000 to 1,695,000 . 7 1,695,000 to 2,130,000 8 2,130,000 to 2,605,000 9 2,605,000 to 3,120,000 10 3;120,000 to 3,675,000 ' Number of Spaces Other Commercial and Industrial Buildings (30% minimum large spaces) 1 • Under 10,000 2 10,000 to 25,000 3 25,000 to 85,000 4 85,000 to 155,000 5 .155,000 to 235,000 6 235,000 to 325,000 7 325,000 to 425,000 8 425,000 to 535,000 9 535,000 to 655,000 10 - 655,000 to 775,000 11 775,000 to 925,000 These requirements may be modified as a Type 4 decision, where the Planning Commission or, on appeal, the City Council finds that such reduction will not result in, injury to neighboring property or obstruction of fire lanes or traffic and will be in harmony with the purposes and intent of this chapter. (Ord. 1795 §2(part), 1997; Ord. 1770 §33, 1996; Ord. 1758 §1(part), 1995) 18.56.070 Cooperative parking facility. A. Shared Parking: When two or more property owners agree to enter into a shared parking agreement, the. setbacks and landscaping requirements on their common property line(s) may be waived with that land used for parking, driveway and/or building. ' B. Covenant Parking: When off-site parking is' provided on a lot other' than the lot of the use to which it is accessory, the following conditions shall apply: 1. A covenant between the owner or opera- tor of the principal use, the owner of the parking spaces and the City stating the responsibilities of the parties shall be executed. This covenant and accompanying legal descriptions of the principal use and the lot upon which the spaces are to be located shall be recorded with King County, and a copy with the recording number and parking layouts shall be submitted as part of any permit application for development. 2. The covenant lot must be within 800 feet of the primary commercial use or a shuttle service to the use must be provided with its route, service and operations approved by the Director. C. When any Shared or Covenant parking agree - ment between .parties, as referenced above, is modified or terminated, the owner of the parking spaces shall be responsible for notifying the Director. In this event, all affected parties shall provide documentation that a minimum of 50% of the required minimum parking will be available within 90 days following termination of the agreement, with the remainder to be available 365 days following termination of the original agreement. If a variance is sought, the application must be submitted within 14 days of the .signed agreement to terminate and the reduction in parking spaces will only be allowed if the variance is approved. D. Complementary Parking: A complementary use is a portion of the development that functions differently than the primary use but is designed to serve or enhance the primary land use without creat- ing additional parking needs for the primary traffic gen- erator. Up to 10% of the useable floor area of a building or facility may be occupied by a complementary use without providing parking spaces in addition to the number of spaces for the principal use. Examples of complementary uses include pharmacies in hospitals or medical offices, food courts or restaurants in a shop- ping center or retail establishments. E. Applications for shared, covenant or comple- mentary parking shall be processed . as Type 2 decisions, pursuant to TMC 18.108.020. (Ord. 1795 §2(part), 1997; Ord. 1758 §1(part), 1995) 18.56.080 Parking for the handicapped. All parking provided for the handicapped, or others meeting definitions of the 1991 Americans with Disabilities Act (ADA), shall: -meet requirements of the Chapter 11 of the 1994 Uniform Building Code, as amended by Washington Administrative Code, section 51.30, et seq. (See Figure 18-8.) (Ord. 1795 §2(part), 1997; Ord. 1758 §1(part), 1995) 18.56.090 Compact car allowance. A. A, maximum of 30% of the total off-street parking stalls may be permitted and designated for compact cars. B. Each compact stall shall be designated as such, with the word COMPACT printed onto the stall, in a minimum of eight -inch letters and maintained as such over the life of the use of both the space and the adjacent structure,it serves. C. Dimensions of compact parking stalls shall conform to the standards as depicted in Figure 18-6 of this chapter. Printed November 3, 1997 • CONVERSATION RECORD DATE: / 1-, / Z— 17 MON TUE WED THU SAT SUN TIME:A. //'OCJ .M. TYPE: ,Visit 0 Conference ❑ Telephone— 0Incoming °Outgoing Name of�erson(s) contacted or in contact with you: ,k? 4 A, -)n e12 *VV Organization (office, dept., bureau, etc.) FOR OFFICE USE ONLY Telephone No.: Location of Visit/Conference: SUBJECT: 1.„97 .0 0711 ,.b -/o T2 yr SUMMARY: /22-4 zw z -Cf — d�% ccs'.. c/ 7Z(46e,/ cc -14 cl.,/15 o A-) Gill -6 e /e•ON r7`/tl24E LD /Z-/ v e't)/ /TE 2Q c -4l e/E� ,t/ i �i /L% .K -P7/2 -Pa "WA -60.-g- J . LO C Pa) gLe, Cx-f'.c., fig_ (?3 /ZC -1A S B 1 a l�t�zGc G*czGL,c� (2 Signature: Title: Date: City of Tukwila John W. Rants, Mayor Department of Community Development Steve Lancaster, Director NOTICE OF COMPLETE APPLICATION December 5, 1997 Jim Anderson Ruhl-Parr and Associates .3625 - 132nd Ave SE, Suite 100 Bellevue, WA 98006 RE: Application for Design Review (L97-0074) and SEPA checklist (E97-0037), Wendy's Restaurant, 16200 West Valley Highway Dear Mr. Anderson: Your applications, for. Design Review and a SEPA checklist to develop a 3,075 square foot Wendy's Restaurant with Drive-through, has been found to be complete on December 5, 1997 for the purposes of meeting state mandated time requirements. The project has been assigned to Michael Jenkins and is tentatively scheduled fora public hearing before the Planning Commission on January 22, 1997 at 7:00 p.m. To assist in our review, the following materials must also be submitted within 14 days of this letter: o A colorboard, with material samples • A conceptual utility plan, with Water, Sewer, Storm Drainage ,and existing/proposed easements indicated The next step is for you to install the notice board on the site within 14 days of the date of this letter. You received information on how to install the sign with your application packet. If you need another set of those instructions, you may obtain them at the Department of Community Development (DCD). Also, you must obtain a laminated copy of the Notice of Application to post on the board. This notice is also available at DCD. After installing the sign, you need to return the signed Affidavit of Posting to the our office. This determination of complete .application does not preclude the ability of the City to require that you submit additional plans or information, if in our estimation such information is necessary to ensure the project meets the substantive requirements of the City or to complete the review process. I will be contacting you soon to discuss this project. If you need to contact me, my direct line is 431-3685. Sincerely, Michael Jenkins Assistant Planner c:\ nsofficc...lctter\9774comp.doc 6300 Southcenter Boulevard, Suite 11100 • Tukwila, Washington 98188 • 12061431-3670 • Fax 1206) 4 1 -.?66S CITY G0TUKWILA • Department of Community Development 6300 Southcenter Boulevard, Tukwila, WA 98188 Telephone: (206) 431-3670 ENVIRONMENTAL REVIEW (SEPA) APPLICATION SUBMITTAL REQUIREMENTS To submit for SEPA review, provide the items listed above to the Planning Division at 6300 Southcenter Boulevard, Room 100. ❑ 6 copies of the completed and signed environmental checklist. You may use the City's pre-printed form or you may re -type the questions on your computer. If you choose to re -type the form into your computer, be sure to do so accurately. Mistakes or omissions will increase the review time. ❑ 6 sets of the full size plans needed to clearly describe the proposed action. ❑ One set of plans reduced to 8.5" x 11". RECEIVED CITY OF TUKVWILA ❑ Four copies of supporting studies. N 0 V 1 2 1997 ❑ One copy of the checklist application. ❑ One set of mailing labels for all properties 500' from the subject property. (See address label worksheet.) PERMIT CENTER ❑ $325 filing fee. COMPLETING THE CHECKLIST The checklist contains several pages of questions which you are asked to answer. It covers a comprehensive set of topics. As a result, several of the questions may not apply to your project. If a particular question does not apply, simply write N/A underneath. HOWEVER, be aware that many questions apply despite appearing not to. Care needs to be taken in reading and answering the questions to ensure the appropriate response is provided. It is important that accurate and clear information be provided. You may not know all of the answers. Answer each question to the best of your ability. If we find an answer to be insufficient, the City may contact you to ask for more information. Sometimes, after reviewing the checklist, the City will ask you provide additional studies or information. Commonly requested information includes traffic analysis, site topography, soils studies and tree surveys. CITY OF - JKWILA 1 Departmen1116f Community Development • 6300 Southcenter Boulevard, Tukwila, WA 98188 Telephone: (206) 431-3670 SEPA APPLICATION CHECKLIST FOR STAFF USE ONLY: Planner: File Number:. e 7 7 06 Receipt Number: Cross-reference files: Applicant notified of incomplete application: Applicant notified: of complete application: Notice of application issued: RECE�VEfl CITY:: OFTUKWILA NOS 12.1997 A. NAME OF PROJECT/DEVELOPMENT: WENDY'S RESTAURANT B. LOCATION OF PROJECT/DEVELOPMENT: (address and accessors parcel number(s)) 16200 West Valley Highway Tax # 000580-0038-04 Quarter: NW Section: 25 Township: 23N Range: 4F (This information may be found on your tax statement) C. PROJECT DESCRIPTION: Build a 3,075 square foot fast food restaurant with two drive-through windows. Exterior to be wood frame with brick veneer and a built-up roof. There will also be a CMU trash enclosure. D. APPLICANT: NAME: Wendy's International ADDRESS: 555 South Renton Village Place, Suite 200, Renton, WA 98055 PHONE: 425-235-8570 FAX: 42 -226-7240 SIGNATUR DATE: /r' /0 17 Wendy's International Tukwila, Washington TECHNICAL INFORMATION REPORT IEXPIRES: 5 / 22 / Prepared by: Washington Land Design 10700 Meridian Avenue North, Suite 503 Seattle, Washington 98133 Contact: Bill Dunning, P.E. Phone: (206) 365-9510 FAX: (206) 365-0225 November 10, 1997 /40 ?(#040, CITyRECEIVED OF TUKWILA NOV 1G1997 PERMIT CENTER TABLE OF CONTENTS I. Project Overview II. Preliminary Conditions Summary III. Off -Site Analysis IV. Retention/Detention Analysis and Design and Biofiltration Swale Calculations V. Conveyance Systems Analysis and Design VI. Special Reports and Studies VII. Basin and Community Planning Areas VIII.Other. Permits IX. Erosion/Sedimentation Control Design X. Bond Quantities Worksheet, Retention/Detention Facility Summary Sheet and Declaration of Covenant XI. Maintenance and Operations Manual LIST OF FIGURES Figure 1 Technical Information Worksheet Figure 2 Vicinity Map Figure 3 Existing Condition of Site Figure 4 Developed Condition of Site King County Building and Land Development Division TECHNICAL INFORMATION REPORT (TIR) WORKSHEET PART 1 . PROJECT OWNER AND PROJECT ENGINEER Project Owner WENo?s TutEluntwiwg, iuc. AESSoR, Address SSS' Soyµ RI urn(' v ► Lt..04g PLA -LE * Zoe k&&' b,J , wek 58053 Phone Project Engineer Company W4S41N61Z9n. L4Nrr DF_.S1bA) D��wvn /6 Address Phone 0 I' 98 zp 1 0 PART 3 TYPE OF PERMIT APPLICATION El Subdivision Short Subdivision = Grading Commercial Other [1 [x1 Page 1 of 2 PART 2 PROJECT LOCATION AND DESCRIPTION Project Name Wr:NO11$ FE 5 r RA Ali Location Township Z3 4). Range 4 E. Section Z S Project Size O.7 3 AC Upstream Drainage Basin Size N/A AC PART 4 OTHER PERMITS DOF/G HPA 0 COE 404 DOE Dam Safety FEMA Floodplain COE Wetlands 71 Shoreline Management —1 Rockery Structural Vaults 0 Other DHPA PART 5 SITE COMMUNITY AND DRAINAGE BASIN Community ciTy of TOKwi LA Drainage Basin Glege iu RtUER. £AsiAi PART 6 SITE CHARACTERISTICS n River Stream E1 Critical Stream Reach I I Depressions/Swales ij Lake = Steep Slopes Lakeside/Erosion Hazard Floodplain Wetlands 71 Seeps/Springs High Groundwater Table Groundwater Recharge P1 Other • PART 7 .SOILS Soil Type URBAN Slopes 1ESS TAL41V Z%a Additional Sheets Attatched Erosion Potential Sc,/ GM771-01✓ Erosive Velocities /,46H 1/90 Page 2 of 2 King County Building and Land Development Division TECHNICAL INFORMATION REPORT (TIR) WORKSHEET PART 8 DEVELOPMENT LIMITATIONS 0001110011 REFERENCE Ch. 4 - Downstream Analysis Additional Sheets Attatched LIMITATION/SITE CONSTRAINT PART 9 ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION Sedimentation Facilities Stabilized Construction Entrance Perimeter Runoff Control Clearing and Grading Restrictions Cover Practices Construction Sequence Other MINIMUM ESC REQUIREMENTS FOLLOWING CONSTRUCTION Stabilize Exposed Surface Remove and Restore Temporary ESC Facilities Clean and Remove All Silt and Debris Ensure Operation of Permanent Facilities Flag Limits of NGPES Other PART 10. SURFACE WATER SYSTEM I5 I Grass Lined Channel Pipe System i l Open Channel n Dry Pond Wet Pond Brief Description of System Operation Tank Infiltration Vault Q Depression Energy Dissapator Q Flow Dispersal Wetland Waiver Stream Regional Detention SVsrgm Method of Analysis Compensation/Mitigation of Eliminated Site Storage 11 Com PoSEn aF c44-2.4 LQbs«vS Amt. c.o_,s1li._YaoucE" � t F . W #r -Y -SWEET PLo LA" 7-o (. PA-itpi /24•J .us 1.ci1}E,eF i i IS Go ALV F YF_Li 70 0►5S.MAR6L- (kw/0; Facility Related Site Limitations 4N-6're D6rENri.d.v mor REs.oc-6.4• Additional Sheets Attatched Reference Facility Limitation PART 11 STRUCTURAL ANALYSIS (May require special structural review) fl Cast in Place Vault Q Other j Q Retaining Wall ! I Rockery > 4' High Structural on Steep Slope Ti Drainage Easement Access Easement Native Growth Protection Easement n Tract Other PART 14 SIGNATURE OF PROFESSIONAL ENGINEER 1 or a civil engineer under my supervision have visited the site. Actual site conditions as observed were incorporated into this worksheet and the attatchments. To the best of my knowledge the information provided here is accurate. syr.rc.e. SECTION I Project Overview Project Overview The proposed project will consist of the construction of a Wendy's restaurant approximately 3,500 square feet in size, with associated parking, landscaping and on-site infrastructure. The project site is located along West Valley Highway, in the Green River Basin, Section 25, Township 23 North, Range 4 East (See Figure 2), adjacent to a proposed BP Gas Station/convenience store. The parcel is approximately 0.73 acre and is relatively flat, sloping gently to the northeast. Existing Conditions The existing site consists of an asphalt paved parking area, with landscaped planters, which provided parking for the former Andy's Diner. The existing site collects storrnwater runoff from two catch basins, one located near the middle of the parking lot, and the other located to the east. The overall site topography slopes from the southwest portion of the property to the northeast portion. Existing elevations vary between 24 and 22 feet. V CI\ T VA D \OT TO SCALE SECTION II Preliminary Conditions Summary Preliminary Conditions Summary This section will address the requirements set forth by the King County Surface Water Management Design Manual Core and Special Requirements listed in Chapter 1. King County Surface Water Management Design Manual Core Requirements 1. Discharge at a natural location (1.2.1): Flow from the site currently discharges to the east via conveyance pipes. The developed site will discharge to the northeast via a proposed 12" stub -out to be provided by the proposed BP station development. 2. Off-site Analysis (1.2.2): A level 1 downstream analysis for the downstream tributary was performed by others. Please refer to the attached Surface Water Technical Information Report by David Evans and Associates, Inc., dated December, 1996. 3. Runoff Control (1.2.3): A. Peak Rate Runoff Control: No detention will be provided as this project does not increase stormwater runoff flows, since the site is currently paved, and the developed condition will not increase impervious area. B. Biofiltration: Biofiltration facilities have been designed to meet DOE water quality requirements for site impervious surfaces subject to traffic through the use of a swale. 4. Conveyance Facilities (1.2.4): Closed pipe systems used to convey on-site runoff will be designed to carry the 25 -year event flow and provide a minimum of 0.5 feet of freeboard between the hydraulic grade line and the top of the structure. 5. Erosion/Sedimentation Control Plan (1.2.5): Erosion control measures are outlined in Section IX. 6. Maintenance and Operation (1.2.6): Maintenance and Operations are covered in Section X. No special maintenance will be necessary. 7. Bonds and Liability (1.2.7): This issue is covered in Section XI. King County Surface Water Management Design Manual Special Requirements 1. Critical Drainage Areas (1.3.1): This project does not lie within a critical drainage area. 2. Compliance with an Existing Master Drainage Plan (1.3.2): The project is located within the Tukwila Nelson Place/Longacres Way Sub -basin which lies within the Green River Basin. This project complies with improvements identified in the Tukwila Nelson Place/McLeod/Boeing CSTC Storm Drainage Study Technical Report. 3. Conditions. Requiring a Master Drainage Plan (1.3.3): The project does not require a master drainage plan. 4. Adopted Basin or Community Plans (1.3.4): The project drainage report and plans were prepared in conformance with the. City of Tukwila Surface Water Standards Ordinance No. 1755 and King County Green River Basin Plan. 5. Special Water Quality Controls (1.3.5): The project will decrease the impervious area which is subject to vehicular traffic. Therefore, no special water quality controls are required. 6. Coalescing Plate Oil/Water Separators (1.3.6): The project will not increase impervious area subject to vehicular use by five acres or more within a given drainage basin. Therefore, no coalescing plate oil/water separators are required. 7. Closed Depressions (1.3.7): The project is not tributary to a closed depression. 8. Use of Lakes, Wetlands or Closed Depressions for Peak Rate Runoff Control (1.3.8): The project will not use a lake, wetland or closed depression for peak runoff control. 9. Delineation of 100 -Year Floodplain (1.3.9): The project is not located within any FEMA designated floodplain. 10. Flood Protection Facilities for Class 1 and 2 Streams (1.3.10): There are no Class 1 or 2 streams within the project area, therefore, no flood protection facilities are proposed. 11. Geotechnical Analysis and Report (1.3.11): The Geotechnical Analysis for the site was prepared by Mayes Testing Engineers, dated September, 1997. 12. Soils analysis and report (1.3.12): The soils underlying this project have been mapped by the United States Department of Agriculture Soil Conservation Service. The maps, issued in November, 1973, identify the soils as "Urban," which is classified as a variable soil type. Sensitive Areas Ordinance Requirements According to the Sensitive Areas Map Folio, there are not sensitive areas located within or adjacent to this project. Project: %O KW 1 LA, Description: Washington Land Design Planning • Engineering w(A,o r`s Date: Job -R/17 By: [:SS FXI,ST)AJ Gr) A)1Oi 7.7 ofUS Torte rE i4RSA 31 � 80 16 ,SF . (0, 73 ,4c.) PERvtovs ,S4 -S7 35- -sF (0. 13 4 (-) IMPEp.vloos AREA = 2.61 3z3 .24 SF (O,Lo 4c.) CN :(PER.vLws) GN (iintoR2vtau� 85 cl Z Y2:srortw4 Z.O „v �o Y t. z 4 42 sro,Z4t -=- Z. 9' i Nfoo Y2 i4- )+R- ,STo2r11 PROPOS' En C'oivn, T1 CVUS PE viovs A-&4 — 6,300 .SP (a. 14. A.c.) T M PEkv sous A 2EA - Z j, 3-45 , - f (O, 5-9 i4c.� MO-.SW/4LE % ma. S7 R. Jt'l (P E& D,O, E,) Pf4v►ovs A2E4 = 6, 30 0 s F (o. H. Ac) I M PER_vtovs r1 ,4- = Z 2 , 43 5 P (O . S1 ) 6 .Mo. 2.4 N2 -sib Awl = 1,33 ,ni. 10700 Meridian Avenue North, Suite 503, Seattle, Washington 98133 (206) 365-9510 Fax: (206) 365-0225 11/4/97 - page TUKWILA WENDY'S BASIN SUMMARY BASIN ID: 100YR-EX NAME: 100 -YEAR EXISTING SBUH METHODOLOGY TOTAL AREA 0.73 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE TYPE1A PERV IMP PRECIPITATION 3.90 inches AREA..: 0.13 Acres 0.60 Acres TIME INTERVAL 10.00 min CN 85.00 98.00 TC 5.00 min 5.00 min ABSTRACTION COEFF: 0.20. PEAK RATE: 0.56 cfs VOL: 0.21 Ac -ft TIME: 480 min BASIN ID: 10YR-EX NAME: 10 -YEAR EXISTING SBUH METHODOLOGY TOTAL AREA 0.73 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE TYPE1A PERV IMP PRECIPITATION 2.90 inches AREA..: 0.13 Acres 0.60 Acres TIME INTERVAL 10.00 min CN 85.00 98.00 TC 5.00 min 5.00 min ABSTRACTION COEFF: 0.20 PEAK RATE: 0.40 cfs VOL: 0.15 Ac -ft TIME: 480 min BASIN ID: 2YR-EX NAME: 2 -YEAR EXISTING SBUH METHODOLOGY TOTAL AREA 0.73 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE TYPE1A PERV IMP PRECIPITATION 2.00 inches AREA..: 0.13 Acres 0.60 Acres TIME INTERVAL 10.00 min CN • 85.00 98.00 TC 5.00 min 5.00 min ABSTRACTION COEFF: 0.20 PEAK RATE: 0.26 cfs VOL: 0.10 Ac -ft TIME: 480 min 11/4/97 _ page 1 TUKWILA WENDY'S BASIN SUMMARY BASIN ID: 100YR-DV NAME: 100 -YEAR DEVELOPED SBUH METHODOLOGY TOTAL AREA 0.73 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE TYPE1A PERV IMP PRECIPITATION 3.90 inches AREA..: 0.14 Acres 0.59 Acres TIME INTERVAL 10.00 min CN 85.00 98.00 TC 5.00 min 5.00 min ABSTRACTION COEFF': 0.20 PEAK RATE: 0.56, cfs VOL: 0.21 Ac -ft TIME: 480 min BASIN ID: 10YR-DV NAME: 10 -YEAR DEVELOPED SBUH METHODOLOGY TOTAL AREA 0.73 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE TYPE1A PERV IMP PRECIPITATION 2.90 inches AREA..: 0.14 Acres 0.59 Acres TIME INTERVAL 10.00 min CN 85.00 98.00 TC 5.00 min 5.00 min ABSTRACTION COEFF: 0.20 PEAK RATE: 0.40 cfs VOL: 0.15 Ac -ft TIME: 480 min BASIN ID: 2YR-DV NAME: 2 -YEAR DEVELOPED SBUH METHODOLOGY TOTAL AREA 0.73 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE TYPE1A PERV IMP PRECIPITATION 2.00 inches AREA..: 0.14 Acres 0.59 Acres TIME INTERVAL 10.00 min CN 85.00 98.00 TC 5.00 min 5.00 min ABSTRACTION COEFF: 0.20 PEAK RATE: 0.26 cfs VOL: 0.10 Ac -ft TIME: 480 min • 1 EXISTING CONDITION WENDY'S FEE = .25.00 DEVELOPED CONDITION SECTION 111 Off -Site Analysis Off -Site Analysis Please refer to the attached Surface Water Technical Information Report by David Evans and Associates, Inc., dated December, 1996. SECTION IV Retention/Detention Analysis and Design Retention/Detention Analysis and Design No retention/detention analysis or design is required nor was performed for this project. In accordance with Core Requirement #3 in the King County Surface Water Design Manual, this project proposes Tess than 5,000 Sf of new impervious surface and therefore, is not obligated to provide detention facilities. Biofiltration Swale Calculations Due to the fact that the impervious area on the site that is subject to vehicular use is proposed to decrease, this site is not subject to standard requirements for water quality. However, the proposal calls for the installation of a biofiltration swale for the parking lot and circulation area. Sizing of this facility is based on the 6 -month storm event meeting the Department of Ecology design requirements. See attached sheet for sizing calculation for this facility. 11/4/97 page 1 TUKWILA WENDY'S BASIN SUMMARY BASIN ID: 6-MODV NAME: 6 MO. DEVELOPED SBUH METHODOLOGY TOTAL AREA 0.65 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE TYPE1A PERV IMP PRECIPITATION 1.33 inches AREA..: 0.14 Acres 0.51 Acres TIME INTERVAL 10.00 min CN 85.00 98.00 TC 5.00 min 5.00 min ABSTRACTION COEFF: 0.20 PEAK RATE: 0.14 cfs VOL: 0.05 Ac -ft TIME: 480 min Washington Land Design Planning • Engineering Project: Tu kto1-4 , 1,JE/'3V'S Description: Date: 10/2.9/47 By: SSS /Do F1Lir°A'rLOnJ suiAt-ELEL4rlory • Eiv6T'H OF Sw4-E — 76 FT • Q fon. 7-4E..4 - wo, Z4 i+ STt) O, 14 PS 54oPE 1.0 ° (604/6 1 .rueimi4Z. St o)sE) • f31#NrvlMG's caEr-F,c,E,ti1 = h ; Oro7 • S pr S to,°E - Z = 3 , AJf 1 ,w6Pk/ 0.0.E. IZEc.osiksti,v,oi4-r,ov5: • DEPTH oP w4rER = 0.z-5 Fr •-r- • • Z.ab FT sw,4LL.. c' r Qvl vr4LC•/7 tura-F.4cC n-0_64. MA,VNiv6's f -4v A-no4) J°RopvcFs Lrivoof WA4.r-R sv,tF,4cE i o row wt erg of slA./A G E. = L.wS /, 7 S' 13 _ O•Z t.ws `3 Y/ 1-8—'1 8011brv1 J F o E d r- A FaR, ZOOL. F -5 %A/ SA — so -SF F'►vp ThE G. a u S •• F41•0E 4-12-E4 fort = L.76- SA- z 6 SA.z SO = 7$3 �= 0,67 Ust Q- 1.0 10700 Meridian Avenue North, Suite 503, Seattle, Washington 98133 (206) 365-9510 Fax: (206) 365-0225 SECTION V Conveyance System Analysis and Design Conveyance System Analysis and Design The proposed on-site conveyance system has been designed using the Santa Barbara Urban Hydrograph as implemented in Waterworks software by Engenious Systems, Inc. The following calculations show that the proposed conveyance system is designed to convey. the 100 -year design storm. The calculations are provided on the following page. 11/4/97 _ page 1 TUKWILA WENDY'S BASIN ID: 100YR-DV SBUH METHODOLOGY TOTAL AREA RAINFALL TYPE PRECIPITATION TIME INTERVAL BASIN SUMMARY NAME: 100 -YEAR DEVELOPED 0.73 Acres TYPE1A 3.90 inches 10.00 min ABSTRACTION COEFF: 0.20 PEAK RATE: 0.56 cfs VOL: BASEFLOWS: 0.00 cfs PERV IMP AREA..: 0.14 Acres 0.59 Acres CN 85.00 98.00 TC 5.00 min 5.00 min 0.21 Ac -ft TIME: 480 min Washington Land Design Planning • Engineering Project: TUku/t L,4 1 W E un p's Description: Date: 11 /1'11'7 By: 065 Co N vr4itiGE CA-C.cS, DE ELDio1 /oo YR a - o.56 cPs Zq 1/4 S To,Z Ii^ (stE ATT. *chtEO .sivEET A SS Li m E S A - -1- ST o/i - S1 T,E DSA. _ /O" SGoPB = o 5 c A D,ofi vS/,vG Aivfv j rvc 1-S FQ - Q = /, 75_ c 'YA-X Q THE b" PIPE c,4,v /toLO) x.75 o,s6 /0" Pi PE �. 10700 Meridian Avenue North, Suite 503, Seattle, Washington 98133 (206) 365-9510 Fax: (206) 365-0225 SECTION VI Special Reports and Studies SEP 19 1997 SUBSURFACE EXPLORATION AND GEOTECHNICAL ENGINEERING REPORT WENDY'S RESTAURANT Tukwila, Washington PREPARED FOR Wendy's International, Inc. MTE Project No. 25997 September 1997 MAYES TESTING ENGINEERS MAYES TESTING ENGINEERS, INC. SUBSURFACE EXPLORATION AND GEOTECHNICAL ENGINEERING REPORT WENDY'S RESTAURANT 16200 WEST VALLEY HIGHWAY (SR 181) TUKWILA, WASHLNGTON September 17, 1997 Project No. 25997 L PROJECT AND SITE CONDITIONS 1.0 INTRODUCTION This report presents the results of our subsurface exploration and geotechnical engineering study for the proposed Wendy's Restaurant in Tukwila, Washington. The proposed building location and approximate locations of the explorations accomplished for this study are presented on the Site and Exploration Plan, Figure 1. In the event that any changes in the nature, design, or location of the structure are planned, the conclusions and recommendations contained in this report should be reviewed and modified, or verified as necessary. 1.1 Purpose and Scope The purpose of this study was to provide subsurface data to be used in the design and development of the subject project. Our study included a review of available geologic literature, drilling exploration borings and performing geologic studies to assess the type, thickness, distribution and physical properties of the subsurface sediments and shallow ground water conditions. Geotechnical engineering studies were also conducted to determine suitable foundation types, allowable soil bearing pressures, anticipated settlements, liquefaction potential, floor support recommendations, drainage considerations, and pavement recommendations. This report summarizes our current field work and offers development recommendations based on our present understanding, of the project. 1 917 - 134th St. S.W., Suite A-1 • Everett, WA 98204 • (425) 742-9360 • FAX (425) 745-1737 1.2 Authorization Authorization to proceed with this study was granted by Mr. Garry Gracey as an agent for Wendy's International, Inc. This report has been prepared for the exclusive use of Wendy's International, Inc. and their agents, for specific application to this project. Within the limitations of scope, schedule and budget, our services have been performed in accordance with generally accepted geotechnical engineering and engineering geology practices in effect in this area at the time our report was prepared. No other warranty, expressed or implied is made. 2.0 PROTECT AND SITE DESCRIPTION This report was completed with an understanding of the project based on an undated site plan with proposed building location provided by Ruhl-Parr & Associates. Present plans call for the single -story structure to use conventional wood -frame construction with a slab -on -grade floor. The restaurant will be located in roughly the central portion of the Phase 2 development area of the property. Site development will also include construction of asphalt paved parking areas, a concrete drive-thru lane, and a garbage dumpster enclosure. Finish floor and parking grades were not available at the time of this report. However, based on a telephone conversation with Mr. Jim Anderson at Ruhl-Parr & Associates, no cutting or filling is planned on the site. The property was situated at 16260 West Valley Highway (SR 181) in Tukwila, Washington. The subject area for this study consisted of only the Phase 2 development area for the Wendy's restaurant. The 230 foot east -west by 130 foot north -south, rectangular parcel was generally level and was approximately lfz to 1 foot below the surrounding street grades. It should be noted that 6 to 8 inches of standing surface water was present within the proposed building location 3 days prior to the time of our field exploration. This water was apparently caused by a plugged drain on the site. Remnants of past development included asphalt pavement with overgrown parking islands, and buried electrical and storm= water utilities. On the parcel to the north, a restaurant was recently demolished. An operating fast food restaurant was located to the south. 3.0 SUBSURFACE EXPLORATION Our field study included drilling a series of exploration borings to gain subsurface sediment and shallow ground water information about the site. The various types of sediments, as well as the depths where characteristics of the sediments changed, are indicated on the exploration logs presented in the Appendix. The depths indicated on the logs where conditions changed may represent gradational variations between sediment types in the field. If changes occurred between 2 MAYES TESTING ENGINEERS sample intervals in our borings, they were interpreted. .Our explorations were approximately located in the field by measuring from known site features shown on the aforementioned site plan. The conclusions and recommendations presented in this report are based on the 4 exploration borings completed for this study. Because of the nature of exploratory work below ground, interpolation of subsurface conditions between and beyond field explorations is necessary. It should be noted that differing subsurface conditions may sometimes be present due to the random nature of deposition and the alteration of topography by past grading and/or filling. The nature and extent of any variations between the field explorations may not become fully evident until construction. If variations are observed at that time, it may be necessary to re-evaluate specific recommendations in this report and make appropriate changes. 3.1 Exploration Borings The exploration borings. were completed by advancing a 4-1/4 inch inside -diameter, hollow -stem auger. During the drilling process, samples were obtained at generally 2.5 or 5.0 foot depth intervals. The borings were continuously observed and logged by a geotechnical engineer from our fu -m. The exploration logs presented in the Appendix are based on the field logs, drilling action,, and inspection of the samples secured. Disturbed but representative samples were obtained by using the Standard Penetration Test procedure in accordance with ASTIVI:D 1536. This test and sampling method consists of driving a standard 2 inch outside -diameter, split barrel sampler a distance of 18 inches into the soil with a 140 pound hammer free -falling a distance of 30 inches. The number of blows for each 6 inch interval is recorded and the number of blows required to drive the sampler the final 12 inches is known as the Standard Penetration Resistance ("N") or blow count. If a total of 50 is recorded within one 6 inch interval, the blow count is recorded as 50 blows for the number of inches of penetration. The resistance, or N -value, provides a measure of the relative density of granular soils or the relative consistency of cohesive soils; these values are plotted on the attached boring logs. The samples obtained from the split barrel sampler were classified in the field and representative portions placed in water -tight containers. The samples were then transported to our laboratory for further visual classification and laboratory testing, as necessary. 4.0 SUBSURFACE CONDITIONS Subsurface conditions on the parcel were inferred from the field explorations accomplished for this study, visual reconnaissance of the site and review of applicable geologic literature. As shown on the field logs, the exploration holes generally encountered silty sand fill overlying natural silt 3 MAYES TESTING ENGINEERS and sand alluvium. The following section presents more detailed subsurface information organized from the upper (youngest) to the lower (oldest) sediment types. 4.1 Stratigraphy Eill Fill soils (those not naturally placed) were encountered in all of the borings. The fill ranged in thickness from approximately 3 feet in EB -3 and EB -4 to 8 feet in EB -2. As noted on the exploration logs, the fill generally consisted of loose, moist to saturated, brown, silt and sand with some gravel. These materials appear to vary in both quality and depth across the site. Since the quality, thickness and compaction of the fill materials is low or variable, the fill is considered unsuitable for support of the new building. ALIT/ulna_ Beneath the fill soils, we encountered a zone of softlloose, wet becoming saturated, dark brown to black interbedded silt, sand and clay. These soils extended below the termination depth of 11' feet in EB -3 and EB -4. In EB -1 and EB -2 these softlloose soils extended to 30 feet and 35 feet respectively. These soft/loose soils were interpreted as alluvial flood plain deposits from the Green River. At a depth of 30 feet (EB -1) and 35 feet (EB -2) a medium dense, saturated, black, fine to medium sand was encountered. This sediment was also interpreted to be alluvium that was deposited by the Green River. Borings EB -1 and EB -2 were terminated in this material at 411/2 and 5E1/2 feet respectively. 4.2 Hvdrologv Ground water was encountered in all our exploration borings below a depth of about 10 feet while drilling and is likely a seasonal, regional, water table. This water table will likely persist year round and experience seasonal fluctuations in elevation with changes in precipitation and river levels. We expect the observed water table to be a seasonal low and that the water level may rise to near surface elevation during wetter times of the year. As previously noted herein, a large area of standing water was observed covering the approximate building footprint 3 days prior to our field work. This information was provided to the architect, Ruhl-Parr & Associates. 4 MAYES TESTING ENGINEERS September 17, 1997 Project No. 25997 II.. DESIGN RECOMMENDATIONS 5.0 INTRODUCTION Our exploration indicates that, from a geotechnical standpoint, the parcel is suitable for the proposed development provided the recommendations contained herein are properly implemented. Due to the thick sequence of soft/loose alluvial soils, the foundation bearing stratum on the site is relatively deep. Foundation alternatives that were evaluated for building support include preloading of the site to pre -consolidate the loose/compressible material followed by construction of shallow spread Footings, construction of a raft slab, and the installation of a deep foundation system (piles). Up to 35 feet of soft/loose interbedded silt, sand and clay soils were encountered on the site. Underlying the soft/loose silt, sand and clay, medium dense sand soils were found to extend to beyond the termination depth of 411/2 feet (EB -1) and 561/2 feet (EB -2) of the deep exploration borings. Within the loose soils, zones with high liquefaction potential were identified at depths ranging from approximately 10 to 30 feet. During periods of higher ground water elevations the saturated portions of the shallower, loose sand sediments would also have a- high . risk of liquefaction. In general, the liquefaction risk and damage potential can be mitigated by use of a pile foundation that extends through liquefaction -prone soils, ground densification or improvement to reduce the liquefaction potential, or use of a shallow raft slab/grade beam foundation supported on structural fill. Preloading has a minimal reduction of the liquefaction risk, would not meet the current construction schedule, and therefore will not be considered further in this study. Pavements can be supported by recompacted existing fill or structural fill that is placed atop recompacted exiting fill. Recommendations for preparation of the subgrade are discussed in the Site Preparation section of this report. Since the near surface soils are variable in quality and compaction, there is an increased risk of future settlement and cracking of the new pavement; therefore, the owner should anticipate potentially higher maintenance requirements associated with pavements on this site. Details of our analysis and recommendations for foundation support are outlined in the following sections of this report. It should be noted that the recommendations contained in this report are based on the assumption that no fill (6 inches or less) will be placed on the site. If the planned site elevation differs from this assumption, we should be notified so that we may review our recommendations and make appropriate changes, if necessary. 5 MAYES TESTING ENGINEERS 6.0 LIQUEFACTION The liquefaction potential of the soils at the site was evaluated using the simplified procedure by Seed and Idriss (1971). This procedure uses the Standard Penetration Resistance values obtained from the borings to predict the likelihood of liquefaction at various depths, ground water levels, and maximum ground surface accelerations. For this project, the liquefaction potential for sands with ground water depth of about 10 feet and maximum ground surface acceleration of approximately 0.20g was used. For these conditions, liquefaction potential below the ground water level to a depth of about 30 feet is high. Below about 30 feet, liquefaction is unlikely. Since soil liquefaction can cause large ground deformations and severe damage to structures with conventional shallow foundations, an alternate foundation type is recommended. A deep pile - supported foundation would be a suitable mitigation of the seismic liquefaction potential. A raft slab foundation would not mitigate the liquefaction potential, but would remain intact if liquefaction occurred beneath the site. A raft slab may experience liquefaction induced differential settlement that would require corrective maintenance. 7.0 SITE PREPARATION Site preparation of planned building and road/parking areas should include removal of all existing debris atop the asphalt. In building, concrete pavement and utility areas, the existing asphalt pavement must be removed. If construction is to occur during Wetter times of the year (October 1S` to May 1s`) the existing asphalt surface should be left in place for construction accessand equipment staging areas. In other areas, at the client's discretion, the existing asphalt pavement may either be left in place or removed. If the existing asphalt pavement is left in place, it would then form the base for new asphalt pavement. If it is removed, the following recommendations would apply. Following removal of the existing asphalt pavement, the exposed subgrade should be compacted to a dense, unyielding condition with a minimum 10 ton, smooth drum, vibratory roller, under the observation of a representative of the geotechnical engineer. If the subgrade contains areas where soft/loose surficial soils exist, or are created by construction activities, they should be overexcavated and replaced with structural fill, as described below, or with crushed quarry rock. If soft areas are too extensive to economically excavate, an engineering stabilization fabric may be placed over the subgrade before filling. Specific recommendations for fabric type and placement can be made by the field engineer during construction, as needed, to address subgrade conditions encountered at the time. Near surface soils at the site contain a high percentage of fine-grained material which makes them moisture -sensitive and subject to softening and disturbance when wet. The contractor must use care during site preparation and excavation operations so that the underlying soils are not softened during excavation or compaction. 6 MAYES TESTING ENGINEERS B.0 STRUCTURAL FILL It is our understanding that less than 6 inches of structural fill will be placed to establish desired grades at the site. Structural fill will also be necessary in any overexcavated areas and in utility trenches. All references to structural fill in this report refer to subgrade preparation, fill type, placement and compaction of materials as discussed in this section. After the exposed ground is recompacted and approved, structural fill will be placed to attain desired grades. Structural fill is defined as non-organic soil, acceptable to the field engineer, placed in maximum 8 inch loose lifts, with each lift being compacted to at least .95 percent of the modified Proctor maximum density (ASTM:D 1557). The top of the compacted fill should extend horizontally outward a minimum distance of 5 feet beyond the building foundation or 3 feet beyond pavement edges before sloping down at an angle of 2H: 1V (Horizontal:Vertical). The contractor should note that any proposed fill soils must be evaluated, approved and laboratory tested prior to their use in fills. This would require that we have a sample of the material 48 hours in advance to perform a Proctor test and determine its field compaction standard. Soils in which the amount of fine-grained material (smaller than No. 200 sieve) is greater than approximately 5 percent (measured on the minus No. 4 sieve size) should be considered moisture -sensitive. Use of moisture -sensitive soil in structural fills should be limited to favorable dry weather and dry subgrade conditions. The near surface, on-site soils generally contained significant amounts of silt and are considered moisture -sensitive. At the time of our field work, the on-site, near surface soils, were too wet to use as structural fill. Construction equipment traversing the site when the soils are wet can cause considerable disturbance. If fill is placed during wet weather, or if proper compaction cannot be obtained, a select fill material consisting of a clean, free -draining gravel and/or sand should be used. Free - draining fill consists of non-organic soil with the amount of fine-grained material limited to 5 percent by weight when measured on the minus No. 4 sieve fraction. A representative from our firm should inspect the stripped subgrade and be present during placement of structural fill to observe the work and perform a representative number of in-place density tests. In this way, the adequacy of the earthwork may be evaluated as filling progresses and any problem areas may be corrected at that time. It is important to understand that taking. random compaction tests on a part -tiny: basis will not assure uniformity or acceptable performance of a fill. As such, we are available to aid the owner in developing a suitable monitoring and testing program. 7 MAYES TESTING ENGINEERS 9.0 FOUNDATION RECOMMENDATIONS As discussed in the first half of this report, the proposed building and road/parking areas are underlain by fill and soft/loose soils which are up to 35 feet thick. The depth of these sediments and their soft/loose condition would likely result in excessive total and differential settlement of a conventional, shallow foundation. In addition, the underlying soils, to a depth of about 30 feet, have a high risk of liquefaction during a strong earthquake. Driven timber or auger cast -in-place piling are recommended to mitigate the settlement risks caused by these conditions. A raft slab foundation atop approved structural fill would also be suitable but would be subject to an estimated 2 to 4 inches of uniform settlement during non -seismic (static) conditions. 'Soil liquefaction during a strong seismic event may result in differential settlement and tilting of the raft slab. 9.1 Pile Foundations 9.1.1 Timber Piles Driven timber piles may be used for support of the proposed structure. An advantage of driven piles is that the energy imparted during driving tends to densify adjacent granular soils thus improving subsurface conditions immediately adjacent to the pile tip and shaft. Full -depth treated, timber piles, conforming to ASTM:D-25, driven to a depth of approximately 40 to 45 feet below existing ground surface, should be capable of supporting loads on the order of 16 tons each. Pile lengths must be adjusted if site grades are changed from the elevations at the time of our exploration. The piles should have a tip diameter of at least 8 inches. Pile tips and butts should be banded to reduce damage while driving. Driving can be performed with an air or diesel hammer developing a minimum of 15,000 foot-pounds of energy per blow. Allowable design loads may be increased by one-third for short-term wind or seismic loading. Anticipated settlement of the pile -supported structure is less than one inch. A potential concern that always exists when driving piles in developed areas is the fact that vibrations induced into the subsurface soils can cause settlement of nearby foundations or cracking of walls. If this option is chosen we recommend that adjacent buildings be monitored for vibration and settlement during pile -driving. A photo/video survey of the adjacent structures prior to pile driving would also be appropriate. 9.I.2 Au=ercast Piles Cast -in-place concrete piles (augercast) may also be used for foundation support. We recommend that the placement of all piles be accomplished by a contractor experienced in their installation. We estimate pile lengths will be on the order of 41 to 46 feet for an 18 inch diameter pile with an allowable 15 ton vertical capacity, and an embedment of 11 feet into the bearing strata. Pile length estimates are relative to site grades at the time of our exploration and should be adjusted accordingly if the site is graded prior to pile installation. 8 MAYES TESTING ENGINEERS Allowable design loads may be increased by one-third for short-term wind or seismic loading. Anticipated settlements of augercast pile -supported structures will generally be less than one inch. 9.1.3 Lateral Pile Capacity The majority of lateral resistance to wind and seismic loading will be generated by passive soil pressure against the grade beams. However, timber piles and suitably reinforced augercast piles will provide an additional capacity. The recommended allowable lateral capacity of timber piles installed as discussed above is 2.5 tons each (applied at the pile top), assuming a fixed head condition. The recommended allowable lateral capacity of augercast piles (applied at the pile top), assuming a fixed head condition, is 6 tons each. The lateral capacities above were determined assuming 0.5 inch of deflection at the pile top with the pile tops fixed to prevent rotation. A factor of safety of 2 was applied to the allowable lateral capacities. 9.1.4 Pile Inspections The actual total length of each pile may be adjusted in the field based on required capacity and conditions encountered during driving or drilling. Since completion of the piles takes place below ground, the judgment and experience of the geotechnical engineer or his field representative must be used as a basis for determining the required penetration and acceptability of each pile. Consequently, use of the presented pile capacities in the design requires that all piles be inspected by a qualified representative from our firm who can interpret and collect the installation data and observe the contractors operations. The geotechnical engineer, acting as the owner's field representative, would determine the required lengths of the piles and keep records of pertinent installation data. A final summary report would then be distributed, following completion of pile installation. 9.2 Raft Slab Foundation A raft slab foundation (structurally connected grade beam and floor slab) may be used for building support when founded on structural fill or recompacted, non-organic fill sediments. Site preparation for the raft foundation should include excavating the entire building footprint, plus a minimum of 5 feet outside the footprint in all directions, to a minimum of 3 feet below the planned grade beam subgrade elevation. Any exposed organic soils or debris should be further excavated as necessary. After the initial excavation is complete, the upper 12 inches of exposed subgrade should be carefully compacted to a dense, unyielding condition using a smooth drum, vibratory roller or hoepac compactor. Once the subgrade is approved, structural fill should be placed to attain the required bottom of slab grade. After filling to bottom of slab grade is completed and approved, the grade beam lines should be excavated. After the grade beam subgrade is inspected and approved by the field engineer, the 9 MAYES TESTING ENGINEERS reinforcing steel may be set and the concrete placed. After the grade beams are cast, the slab - subgrade materials should be placed, including 4 inches of washed pea gravel, a polyethylene plastic vapor barrier, and 2 inches of washed sand over the vapor barrier. The grade beams for the raft foundation should be designed using an allowable soil bearing pressure of 1000 pounds per square foot (psf), including both dead and live loads. No increase in the allowable bearing pressure for transient loading is recommended. The perimeter grade beam for the raft slab foundation should be buried at least 18 inches into the surrounding soil for frost protection. The entire foundation must bear on a minimum of 3 feet of approved structural fill as described herein. Anticipated settlement of the raft slab foundation founded on approved structural fill should be on the order of 2 inches. However, disturbed soil or soft areas not removed from the subgrades prior to grade beam placement could result in increased settlement. All raft slab subgrades should be inspected by a representative of our firm prior to placing concrete to verify that the design bearing capacity of the soils has been attained and that construction conforms with the recommendations contained in this report. Such inspections may be required by the governing municipality. It should be noted that the recommendations for a raft slab foundation, as discussed above, are based on a finish floor elevation within 6 inches of existing conditions. If proposed site grading will require the placement of fill to raise the finished floor elevations in the building area more than 6 inches above existing grade, the foundation recommendations for a raft slab foundation may require modifications. As such, we should be given an opportunity to review grading plans prior to final design work to implement any changes into our foundation recommendations. 9.3 Passive Resistance We understand that a Wendy's sign will be supported by a steel column and founded on an augercast pile. The augercast pile may be designed for passive resistance against lateral translation using an equivalent fluid equal to 165 pounds per cubic foot (pcf). This value only applies to the augercast pile where concrete is placed directly against natural undisturbed soil. The passive resistance value includes a factor of safety equal to 3. in order to reduce the amount of movement necessary to generate passfve resistance. 10,0 FLOOR SUPPORT If the building is to be pile -supported, we recommend that the slab -on -grade floor should also be supported by piles. If the floor slab will not be pile -supported it should not be structurally connected to the pile -supported foundation but should be free to settle independently. The floor should be cast atop a minimum of 4 inches of pea gravel to act as a capillary break. A polyethylene plastic vapor barrier should be used under floors that are likely to receive an 10 MAYES TESTING ENGINEERS impermeable floor finish or where passage of water vapor through the floor is undesirable. Based on American Concrete Institute recommendations, we suggest placing a two.to three inch layer of clean sand over the vapor barrier to protect the vapor barrier and to allow some moisture loss through the bottom of the slab to aid in the curing process. Sand should be used to aid in the fine grading process of the subgrade to provide uniform support under the slab. 11.0 DRAINAGE CONSIDERATIONS At the site, the near surface soil is moisture -sensitive and will be difficult to work on if it becomes wet. Construction traffic on the wet soil will disturb the relatively firm surface; therefore, prior to site work and construction, the contractor should be prepared to provide drainage and subgrade protection as necessary. If possible, construction should be timed to take advantage of seasonally dry weather. If construction is to proceed between October 1 and May 1, existing asphalt surfaces should be left in place until removal is required for construction. All perimeter walls should be provided with a drain at the footing/grade beam elevation. Drains should consist of rigid, perforated, PVC pipe surrounded by washed drain rock. The diameter of the drain rock must be larger than the pipe perforations. The level of the perforations in the pipe should be set approximately 2 inches below the bottom of the footing/grade beam and the drains should be constructed with sufficient gradient to allow gravity discharge away from the building. All drains should discharge into an approved storm water drainage facility. Roof and surface runoff should not discharge into the perimeter drain system but should be handled by a separate, rigid, tightline drain. In planning, exterior grades adjacent to walls should be sloped downward away from the structure to achieve surface drainage. 12.0 PAVEMENT RECOMMENDATIONS As previously stated in this report, the on-site, upper, 30 feet of soil is in a soft/loose condition. As such, some remedial action to improve the subgrade will likely be necessary prior to paving. This will include replacement of soft soils with structural fill, use of stabilization geotextile fabric or other measures as warranted by subgrade conditions at the time of construction. Increased maintenance should also be anticipated for pavement for this site. It is our understanding that the site will have two types of pavement sections. The drive-thru lane and trash enclosure areas are to be covered with rigid (concrete) pavement, and the remaining traffic lanes and parking areas are to be surfaced with a flexible, asphalt concrete pavement (ACP). The estimated traffic lane volumes are approximately equal to an equivalent single axle loading (ESAL) of 50,000 over the 20 year design life. Our pavement design recommendations are based on this estimated ESAL value and a firm, unyielding subgrade recompacted to a minimum of 90 percent of the modified Proctor maximum density using ASTM:D 1557 as the standard. 11 MAYES TESTING ENGINEERS Subgrade preparation should consist of grading the rigid and flexible pavement areas to at least 11 inches below the top of the finished surface elevation. The subgrade surface should be slightly crowned to drain to the edges of the paved areas. Next, the surface of the exposed soils should be recompacted with a vibratory roller to a minimum of 90 percent of their maximum density as • defined by ASTM:D 1557. After recompaction, the subgrade should be proofrolled with a fully loaded, tandem axle dump truck to identify any soft or "pumping" areas. Proofrolling should be observed by a representative of our firm. If soft areas are observed, they should be overexcavated and backfilled with compacted, free -draining, granular, structural fill. If the excavation depth of soft areas becomes too deep, engineering stabilization fabric should be placed. Fabric should consist of Amoco 2002, or equivalent, installed in accordance with the manufacturer's guidelines and the field engineer's recommendations. 12.1 Flexible Pavement Design Upon completion of the subgrade preparation as described above, the crushed base course, the leveling course and surface pavement may be placed. The recommended flexible pavement section for this site is as follows: 3 inches - Washington State Class "B" Asphalt Concrete Pavement 3 inches - Compacted, 5/8 inch minus crushed surfacing top course 4 inches - Compacted, 1-1/4 inch minus crushed surfacing base course The leveling course and base course materials should be compacted to a minimum of 95 percent of maximum dry density as defined by ASTM:D 1557. If the client decides to leave the existing asphalt pavement in place, we recommend a minimum 11/2 inch thick layer of Washington State Class "B" Asphalt Concrete Pavement be placed as a topping layer. Areas where existing pavement is cracked should have a geotextile placed to mitigate reflective cracking. If it is necessary to fill above the existing pavement to attain desired grade, 5/8 inch minus, crushed surface top course should be utilized. The fill should be compacted as described above. A minimum of 3 inches of asphalt concrete pavement should be placed in any fill areas above existing pavement. 12.2 Rigid Pavement Design Upon completion of the subgrade preparation as described above, the recommend rigid pavement section for the drive-thru lane and trash enclosure areas would be as follows: 12 MAYES TESTING ENGINEERS 5 inches - Portland Cement Concrete (PCC) 5 inches - Compacted, 5/8 inch minus crushed surfacing top course The leveling course material should be compacted to a minimum of 95 percent of maximum dry density as defined by ASTM:D 1557. All concrete should have a minimum of 6 sacks of cement per cubic yard and a minimum of 28 day compressive strength of 4000 pounds per square inch (psi). The concrete should be properly cured a minimum of 7 days immediately after placement. We further recommend that all concrete contain 5 percent entrained air for freeze -thaw protection and be placed at a maximum 2.5 inch slump. The wear surface should be textured with a coarse metal broom or rake finish to provide skid resistance. To allow for an orderly arrangement of the cracking that concrete naturally undergoes during curing, we recommend placement of contraction joints. The depth of the joints should be sawed into the hardened concrete, formed by plastic strips, or tooled into the concrete during placement. Contraction joints should be placed at a maximum of 20 foot intervals. If rigid pavement is- to be used for covering broad expanses, contraction joints should be placed on a maximum 20 foot grid pattern. Expansion joints should be installed at 60 foot intervals along the drive-thru lane: These joints will also function as contraction joints. The expansion joints should. be 3/4 inch wide. All expansion and contraction joints should be filled with suitable filler material. Load transfer dowels should be installed perpendicular to all pavement contraction and expansion joints. These dowels should be 3/4 inch diameter (#6), smooth bars, 18 inches in length, thus allowing 9 inches of penetration on each side of the joint. Load transfer dowels should be spaced 12 inches on -center and be set 3 inches below the concrete surface. Suitable wire mesh reinforcement, properly placed in the upper 1/3 of the slab, should also be provided for all concrete pavement. 13.0 UTILITY CONNECTIONS Due to the soft/loose nature of the soils underlying the site, it would be prudent to provide flexible connectors for all utilities. These connectors should be designed to provide a suitable connection when 2 to 4 inches of settlement may occur. 13 MAYES TESTING ENGINEERS • 1 '1•J •y D :d1P • E: 11 U•di •:1 At the time of this report,_site grading, structural plans, and construction methods have not been finalized. We are available to provide additional geotechnical consultation as the project design develops and possibly changes from that upon which this report is based. We recommend that we perform a geotechnical review of the plans prior to final design completion. In this way, our earthwork and foundation recommendations may be properly interpreted and implemented in the design. We are also available to provide geotechnical engineering and monitoring services during construction. The integrity of the foundation depends on proper site preparation and construction procedures. In addition, engineering decisions may have to be made in the field in the event that variations in subsurface conditions become apparent. We have enjoyed working with you on this study and are confident that these recommendations will aid in the successful completion of your project. If you should have any questions, or require further assistance, please do not hesitate to call. Sincerely, MAYES TESTING ENGINEERS, INC. oseph B. Clare, Geotechnical Consultant 3997 9/1/97 Id - WP7 14 46 OPIAES S /y 95 t Michael J. Mayes, P.E. Principal MAYES TESTING ENGINEERS utn iVattlh Girt WA. V.II grain 143$12. t • 1/2 • • • • •;) 1. • le. C.1\;!; IV °"• :.1}4 4 41 4 1 • (Ail Maw fa OS • .60 LULLi! COMMiCHLi 610/4 MO, • 1410 ANS, L Anal ana fam Iat ..;11.7aZa io • • 6-5 •-(Ji . "a. - J swot - .j.10111. 41. Pa% 1111 t. 00(4'4 e..•.•“0 • r...11f • ••• • : ' I tie EB -31 :re- .••••*? • • •• , nri • 1 ' .... . • . . WV I , I, I I • 1... • i i •4:11.4 OW • % . . .... . il \ . • . ..I ' ' .... 1 ' "." • Ye A , : • _.... ... ....... '. I ,,;. • - . . • • • -7- ` -." - - frrl - ..... .... ... ..... pct..; +1. . , -•-• INIA5E 2 forVb..OFVENI LEGEND Approxknato location EB -1 w or osiploratIon borkni • "'" • Pr7 te.1 _L._ - - • SITE AND EXPLORATION PLAN REFERENCE: RUNL-PARR & ASSOCIATES DRAWING 'WENDY'S SITE PLAN', UNDATED 0 50 100 SCALE Iti FEE r • WENDY'S RESTAURANT TUKWILA, WASHINGTON 25997 • 9/97 FIGURE 1 EXPLORATION BORING LOG Number EB -1 Page 1 of 2 . SEDIMENT DESCRIPTION DEPTH SAMPLE GROUND WATER STANDARD PENETRATION RESISTANCE ooc 10 20 30 40 Surface: 3-1/T asphalt. Wet to saturated, brown SILT. (Fill) — — 5 1 1 1 I T I1 2.. WD 1 • I r A I I T 1 T 1 1 �1 Wet to saturated, brown SILT. Wet, black, fine to medium SAND, trace silt. Saturated, dark brown to black, fine to medium SAND, trace silt. Saturated, dark brown, fine SAND with silt, organics. Saturated, gray, silt y CLAY, trace organics. Saturated, dark brown, fine SAND, trace to some silt. Saturated, gray to dark brown, fine sandy SILT with clay. Saturated, dark brown, clayey SILT wtih trace fine sand. Saturated, gray with some black CLAY with silt, organics, roots. Saturated, dark brown to black, fine to medium SAND; gray silt/clay Tense at top of sample. Saturated, black, fine to medium SAND. - _ . 1 -- 10 — 15 6 — — �Z �2 — 20 0 �- 25 — .2 2 — 30 — 18 , 20 Subsurface conditions depicted represent our observation at the time and 'condos d this aspdoratxy hole. modeled by geologic Interpretations. ef+gineefing erniysis..nd judgment They arts not n.oss arb repre..i v. d otter times and locations. W. we not _ accept responeboty for Its use or Interpretation by others d me0 kttaoe presented on lids log. Reviewed By MAYES TESTING ENGINEERS, INC. Wendy's Restaurant Tukwila, Washington Project No. 25997 August 1997 EXPLORATION BORING LOG Number EB -1 Page 2 of 2 SEDIMENT DESCRIPTION • . = a W 0 SAMPLE GROUND WATER STANDARD PENETRATION RESISTANCE Mown/Foot 10 40 30 40 Saturated. black, fine to medium SAND. : (Alluvium) — 1 15 A — 19- BOH Q41.1/Z WD = while drilling • • — 45 50 — — 55 — 60 65 — Suburbans conditmhs depicted represent eta' obeenratons at the dm* and loceden of thin exploratory hole. meddled by peob* Interpratedone. enpb+.erinp welled. andJudgment Tey are not n.cesserfy repress w. of other tines and loaadona. We we not t� accept raspon.8ilr+or the we or kyerprwton by others of rdormaifon presented en this ba Reviewed By mill - MAYES TESTING ENGINEERS, INC. Wendy's Restaurant Tukwila, Washington Project No. 25997 August 1997 EXPLORATION BORING LOG Number EB -2 Page 1 of 2 SEDIMENT DESCRIPTION DEPTH SAMPLE GROUND WATER STANDARD PENETRATION RESISTANCE act 10 20 30 40 Surface: 3-1/2" asphalt Wet, brown, fine sandy SILT. (Fill) (Fan ? – 1 1 I SZ .WD A0 T 1 — 5 - A 3 s Wet to saturated, brown, silty, fine to medium SAND. Saturated, gray, silty CLAY. Saturated, gray with brown, clayey SILT to sitty CLAY with trace organics (roots). Saturated, gray, silty CLAY with trace organics (roots). Saturated, dark brown, silty, fine SAND. — 10 – 15 A 3 — — 20 – 0 – 25 • 0 — 30 – .2 Subsuzace mentions depicted represent our observations at the time and location of this exploratory hob. modIfisd by psobpb kterPtW.dons. engknrktg snares. rd judgment. They are not n.assry repnauntrdve et other levies and baadora We via not accept onsib$y for the as or ktirptetsdon by others ad ktronnedon presentee on cello log Reviewed By - MAYES TESTING ENGINEERS, INC. Wendy's Restaurant Tukwila, Washington Project. No. 25997 August 1997 EXPLORATION BORING LOG Number EB -2 Page 2 of 2 SEDIMENT DESCRIPTION DEPTH SAMPLE GROUND WATER STANDARD PENETRATION RESISTANCE 10 20 30 40 Saturated, black, fine to medium SAND, trace sfit. Saturated, black, fine to medium SAND. trace silt thin sift lenses. (avium) – i___ 40 1 I I25 I. I• 18 A -4 50 — - £22 - 55 - BOH a 56-1/2' WD = while drilling - 60 — 65 Wasarfacm nonagons depicted represent our observslione at this time and location of this aaploraay hob. moaned by geologic Interpretations. Mglneedng analysis. and Ilk ate not n.easearfy representative of oew Ines and iocettons. We roil not soma responsibility for the tae or r+esrpreladoo by others d rdonnetion presented on tNs log. Reviewed By MAYES TESTING ENGINEERS, INC. Wendy's Restaurant Tukwila, Washington Project No. 25997 August 1997 EXPLORATION BORING LOG Number EB -3 SEDIMENT DESCRIPTION I_. w CI SAMPLE GROUND WATER STANDARD PENETRATION RESISTANCE Blows/Foot 10 20 30 40 Surface: 3-1/2" asphalt. Moist, brown, fine to coarse SAND with occasional gravel (crushed rock). (Fill) (fl) _ T 1 1 1 I A4 A 31 Moist, brown, fine SAND, trace sift.. Moist, brown, silty, fine SAND. - Wet, brown, silty, fine SAND. Saturated, brown silty, fine SAND.(Alluvium) — - 5 A2 - 10 15 WD 2 BOHc11-1/2' WD = while drilling — — 20 — 25 30 — Sub.ertaos oondttlons depicted represent our oh..rvadorw st the drew and tocedon of this expbralory hole. modified by OsctoOk mow. trOlniorina woi. aMIi.cluntent. They -- net neoe.sarly noceseentatIve d other tines and boadoeti We ell not accept reap«wbiny tor thew or Yta.rpn.t don by oiler. of Mbmwtlon prewe>•d on Mk log. Reviewed By MAYES TESTING ENGINEERS, INC. Wendy's Restaurant Kent, Washington Project No. 25997 August 1997 EXPLORATION BORING LOG Number EB -4 . SEDIMENT DESCRIPTION DEPTH SAMPLE GROUND WATER STANDARD PENETRATION RESISTANCE Blows/Foot 10 20 30 40 Surface: 3-1/2' asphalt. Moist, brown, fine SAND with some silt. (Fill) _ _ 1 1 T 11 I 1 7� Wet, brown SILT with some fine sand. Wet, dark brown, fine to medium SAND. Saturated, brown, silty, fine to medium SAND to fine sandy SILT. (Alluvium) _ _ 5 A .4 — 10 – – _ — 15 WD �2 BOH Q 11-1/2' WD = while drilling — 20 — 25 30 — Subsurface oondldons depicted represent our observations at itis time and location of this exploratory hobs, modified by geologic engineering his, and judgment They an not neos+wriy represertzthe of other timed and location. We wi not accept nepa+ebily for the use or ts.rpn adon by others d Momradon presented on this log. Reviewed By , MAYES TESTING ENGINEERS, INC. Wendy's Restaurant Kent, Washington Project No. 25997 August 1997 r SECTION VII Basin and Community Plan Areas Basin and Community Plan Areas Basin Plan (1.3.4-1) The project lies within the City of Tukwila South CBD Basin Plan. The drainage report and plans were prepared in conformance with the basin plan and the requirements outlined in the City of Tukwila Storm Drainage Ordinance No. 1755. Community Plan (1.3.4-1) The project does not lie within an identified Community Planning Area. The plans were prepared in conformance with the City of Tukwila development standards. Master Drainage Plan (1.3.2-1) This project does not require a Master Drainage Plan. Critical Drainage Areas (1.3.1-1) This project does not lie within an identified Critical Drainage Basin. SECTION Vlll Other Permits Other Permits To our knowledge, this project will not require any of the specialized permits or approvals listed on Page 1.1.2-1 in the King County Surface Water Design Manual. SECTION IX Erosion/Sedimentation Control Design Erosion/Sedimentation Control Design The temporary erosion and sedimentation control plan has been designed in accordance with Core Requirement #5 in the King County Surface Water Design Manual. The following is a summary of the way in which we have addressed each of the 11 minimum requirements: 1. Clearing limits. The clearing limits have been clearly delineated on the Temporary Erosion and Sedimentation Control Plan. This area includes any part of the project site that is subject to disturbance as a result of construction activities. 2. Cover measures. Temporary and permanent cover measures shall be provided to protect disturbed areas in accordance with Section 5.4.2 of the King County Surface Water Design Manual. Temporary cover shall be installed if an area is to remain unworked for more than 7 days during the dry season (April 1 to September 30) or for more than 2 days during the wet season (October 1 to March 31). The seed mix that has been specified on the Temporary Erosion and Sedimentation Control Plan is that of the temporary erosion control seed mix. 3. Perimeter protection. Perimeter protection to filter sediment from sheet wash has been located downslope of all disturbed areas and will be installed prior to upslope grading in accordance with Section 5.4.3 in the King County Surface Water Design Manual. Because of the low erosion potential for this site, perimeter protection consists only of silt fences. The Temporary Erosion and Sedimentation Control Plan specifies that 50.linear feet of silt fence (and the necessary stakes) per acre of disturbed area must be stockpiled on-site. 4. Traffic area stabilization. A stabilized construction entrance will be installed as the first step in clearing and grading. 5. Sediment retention. Because of the relatively small size of the site, short flow path length, and shallow slopes across the site, the perimeter silt fence will be utilized for sediment retention. 6. Surface water control. As noted in Item 5 above, the size, length of flow path, and average slope across the site precludes this project from providing surface water control during construction. 7. Dust control. Preventative measures to minimize the wind transport of soil will be taken if a traffic hazard may be created or when sediment transported by wind is likely to be deposited in water resources. 8; Wet season construction. If this project site has exposed soils during the wet season (October 1 to March 31), it shall be subject to the special provisions in Section 5,4.8 in the King County Surface Water Design Manual. 9. Construction within sensitive areas and buffers. To our knowledge, this project does not fall within any sensitive areas or buffers. 10. Maintenance. All temporary erosion and siltation control measures will be maintained and reviewed on a regular basis as prescribed in the Maintenance Requirements for each Best Management Practice in Section 5.4.10 of the King County Surface Water Design Manual. A temporary erosion and siltation control supervisor will be designated by the applicant, and will be responsible for maintenance and review of the temporary erosion and siltation control and for compliance with all permit conditions relating thereto. The name, address and phone number of the supervisor will be supplied to the County prior to the start of construction. The site will be reviewed by the supervisor at least once a month during the dry season, weekly during the wet season, and within 24 hours of significant storms. 11. Final stabilization. Prior to obtaining final construction approval, the site will be stabilized and all of the temporary erosion and siltation control measures will be removed. - SECTION X Bond Quantities Worksheet, Retention/Detention Facilities Summary Sheet and Declaration of Covenant Bond Quantities Worksheet The bond quantities worksheet for this project has been included in the following pages. The quantities in this worksheet have been totaled based on the amounts of the unit prices listed on the form. Retention/Detention Facilities Summary Sheet and Sketch No new retention/detention facilities have been proposed for this project. Declaration of Covenant (privately Maintained Commercial Retention/Detention Facilities Only) No new retention/detention facilities have been proposed for this project. Big City Dapsrtmed et Desdopmmt and Eariroomental Service 3600 !Nab r.©. Sesda.as ii.0...., Wa itypoe 98006-1400 SITE IMPROVEMENT BOND ; QUANTITY WORKSHEET Project Name: W E AMY 5 RES -M. Llie,4W7— Location: W VEST V 14&LEV F} 1 G 14 .M' Y SIERRA Project No.: Sierra Activity No. ENOSIDNA®MEIIT CONTROL FON V Tn1 P OJECT Ottindty ►doe Fence, .It f 1.30 LY 160 #�B NYdro•s•dle0 .40 SY Jute Mash 1.00 SY Much, by hand. straw, 2' deep .35 SY 1 tL c 14zo Mulch, by rnaNirr, strew. 1' deep .40 SY Reck Cane Entrance, SO' x 15' x 1' 1,030.00 Each 1 0,30 Rook Cartr Entrance. 100' x 15' x 1' 1,800.00 Each Seeding.. by Mrd .35 SY 2130 1-20 ESC SUBTOTAL ./O Date: lio/g7 Pdos U&t • EXISTING :. RIGHTOFWAY pant►' ►rbc rutuRE nmlc ROAD M�ROVENENT�: ousnthy. Mo PRIVATE IMPROVEMENTS ' owndty. Hort.. RID FACILITIES AND CONVEYANCE SYSTEIUB'..: .: Ouandty Pde. Ouandty Complete PM Oman*, Complete Fria Ouatdty Complete OMR/a It9AS CMalRarara Brush. by had .24 SY SUBTOTAL FOR PAGE Cwa-411a16- tznra. Pana 1 Sierra Project No. GENERAL ITEMS (Can't.) EXISTING,i:::' `. RIGHT -0F -WAY FUTUitt Hrstic, MVIWVEMENTtj.: �'. PRIVATE <.:, IMPROVEMENTS R/D FACILITIES AND CONVEYANCE SYSTEMS 1 BOND REDUCTIONS 2 . ..... 3 Link Ousnthy Prlw Quantity Polos Qum Price . Quantity Price Quantity Complete Prise Quantity Complete Prior Quantity Complete Price Clasring/Gn/bbing/Removat, trees Excavation - bulk 6,150.00 Acre 0,7 43 5 - 1.10 cY Excavation - trench 3.00 cY /3 39 d B.ckR & Compaction - embankment 8ackrd & Compaction - trench 3.60 cY 5.70 cY 1i0 627 Fif & Compact - damson barrow Fill & Compact - gravel base F U & Compact - screened topsail Grading, Mme, with grader 11.10 cY 15.60 CY 200 15.40 .70 CY SY 4c9 3,000 17.0 616 ZV00 Grading, lire, by had 1.30 SY Fencing, cedar, 6' high 25.00 LF Fencing, chairs hit, 6' high 9.20 LF Fencing, chain felt, gate, 20' 880.00 Each Fencing, temporary (NGPE) Sod 1.10 IF 4.82 SY Monuments, r log 84.00 Each Surveying, tet Ioc.donAines 630.00 Acre Surveying,fne & grade 510.00 Day 5/0 Trail, 4• crushed cinder Trail, 4• top course 6.50 SY 6.00 SY Gabbs, 3' thick, no earthwork 97.00 SY Wag, retaking, rockery w/earthwork 21.00 SF SUBTOTAL won PAOI CA4J7e3e• 12A4114 Page 2 63© 13,230 • Sierra Project No. ROAD t.1PROVEMENTS EXISTING .:..:: . RIOHT-0FWAY'' FUTURE PUOLIC ROAD MAPROVEMENTt,>.;. PRIVATE :;;'.: IMPROVEMENTS RiD FACILITIES AND • CONVEYANCE SYSTEMS . .--.. 3 Unit - Price Unit Ownthy Pri Quantity_ Pdos Qum On Price Quantity Complete Quantity Complete Price Quantity Complete Price AC Grinding, 4' machine 7.00 SY AC Removal/Disposal/Repair Barricade, type 1R Berrtcade, type 1 MKS, extruded asphalt 80.00 SY 30.00 LF 20.00 LF 1.80 IF Curb, extruded concrete Curb i Gutter, rolled Curb & Gutter vertical 1.80 LF 9.30 LF 6.80 Oeme8tlen101epwal, curb & gutter Dem lition/Disposel, sidewalk Saweut, asphalt, 3' depth Sawcut, concrete, per 1' depth Sealant 10.30 IF LF ?SD ZO 630 22.50 SY 470 ( zs6 So47 1.30 IF 1.10 IF .70 IF 2_40 Ibs Shoulder, AC, see AC Road Shoulder, gravel SY 6.40 SY Sidewalk, 4' thick, vertical curb Sidewalk, S' thick, roiled curb Striping, 4' nRectorized line Striping, per parking sten 20.80 SY 40 Thickened Edge 23.80 .20 2.90 4.70 SY 416 LF Each 39 LF ROAD SURFACING 14' rook . 2.5 bees li 1.5" top course) AC OveAey, 1.5' AC AC averts* 2' AC 5.40 6.50 SY SY SUBTOTAL F00 Mae CM4:413e • 13MM Page 3 \--7-,z0.16 iierre I Io. SUBTOTAL FO PAot C/e44ielfe • 12/eM Page 4 EXISTING RIOHT.OF.WAY FUTURE PUBLIC ROAD IMPROVEMENTS PRIVATE IMPROVEMENTS RID FACILITIES AND CONVEYANCE SYSTEMS 1 BOND REDUCTIONS 2 3 Unit Priam Unit Ouen8tf Prim Quantity. Priam Quantity Prism Quantity I Price Ouantlty Complete Priam Quantity Complete Prlos Ouendty Complete hoe ROAD SURFACING Won't.) AC Road, 2', 4' rock, First 2500 SY 13.70 SY AC Road, 2', 4' rock, Oty. over 2500 SY 9.10 SY AC Road, 3', 4' rock, First 2500 SY 18.50 SY , -, . s_ AC Road, 3', 4' rock, Qty. over 2500 SY 11.00 SY AC Road, 5', First 2500 SY 16.30 SY AC Rood, 5', Oty. over 2500 SY 10.80 SY AC Road, S', Ant 2500 SY 19.10 SY I AC Rood, 8', Oty. ova, 2500 SY 12.70 SY Asphalt Treated Base (ATB) (Assume 2.05 ton/cyd) 30.00 Ton Gravel Road, 4' rock, First 2500 SY 7.20 SY Gravel Rood, 4' rock, Oty. over 2500 SY 4.70 SY PCC Road, 5', no bese 14.30 SY PCC Road, 6', no base 16.60 SY DRAINAGE (CPP - Corrugated Plastic Pipe, N-12 or equivalent) Access Road, R/D 9.30 SY Bollards - fixed 290.00 Eech Bollards - removable 475.00 Each (CBs Inehrde frame end lid) CB Type 1 850.00 Eech S +7.50 CB Typal!. 1,000.00 Eech CB Type B, 48' diameter 1,300.00 4' deep for additional depth over 4' +320.00 r I' depth SUBTOTAL FO PAot C/e44ielfe • 12/eM Page 4 Sierra Project No. onsnao RKIKT-GF-WAY Cw�dtp Pdoe: teMROVEtiEfty�. Ou.nthy :. •.PiWATE MPROVEMENTS ". MOO RID FAcIUTIES AND CONVEYANCE.':• SYSTEMS Own Complete: PAM ciumety camp's,. Price Ouandty Complete' Moe DRAINAGE (Can't.) CB Type N, 54' diameter 1,450.00 4' deep for additional depth over 4' +370.00 +1' depth CB Type N. 60' diameter 1,600.00 4' deep for additional depth over 4' +410.00 +1' depth CS Type N, 72' diameter 2,200.00 4' depth for additional depth over 4' +520.00 +1' depth Through -curb Met Framework (Add) 225.00 Each Cleanout, PVC, 4' 86.00 Each Marmot. PVC, 6• 115.00 Each Cleanout. PVC, S' 142.00 Each 3 Culvert. PVC, 4' 4.50 LF Culvert, CPP, 6• 9.30 LF Culvert, PVC, 6' 6.40 LF Culvert, CMP, 8' 9.50 LF Culvert, concrete, 8' 12.90 LF Culvert, CM, B• 10.00 LF Culvert, PVC, 8' 8.00 LF Culvert, CMP. 1r 14.60 LF 7', 4)9 Culvert, concrete, 12' 17.90 LF Culvert. CM, 12' 16.50 LF Z3( 41214.9 Culvert, CUP 15' 18.70 LF Culvert, concrete. 15' 22.50 IF Culvert, CPI". 15' 16.50 LF Culvert. CMP, 1S• 21.90 LF SUBTOTAL FOR Meg CI 44:MMMe • t2A/N Pape 5 55Ba.cto Sierre , ,..,... No. SUBTOTAL FOR PA" barer latae - 1 =AM Page 6 EXISTING : RIGHT -O WAY FUTURE PUBLIC .. ROAD IMPROVEME1FTt.: .. NATE IMPROVEMENTS R/D FACILITIES AND CONVEYANCE SYSTEMS 1 BOND REDUCTIONS 2 .,, :._ 3 Unit Price Unit : Ousnthy Pries (Blandly Price Quantity" . ... ..Price Ouenthy Price Quantity' Complete Mos Ouentlry Complete Price Quantity Complete Moa DRAINAGE (Can't.) Culvert, concrete, 18' 27.60 IF Culvert, CPP, 18' 22.00 LF Culvert, CMP, 24' 30.30 LE Culvert, concrete, 24' 39.80 LF Culvert, CPP, 24' 29.00 LF Culvert. CMP, 30' 38.60 LF Culvert, concrete, 30' 64.70 LF Culvert, CMP, 36' 62.80 LF CuIwrt, concrete, 36' 83.20 LF Culvert. CPP, 36' 39.00 LF Culvert, concrete, 42' 101.80 LF Culvert, CMP, 48' 80.60 LF Culvert, concrete, 48' 113.00 LF Culvert, CMP, 60' 112.00 LF Culvert, concrete, 60' 164.00 LF Ditching, bare, roadside 5.40 CY Row Dispersal Trench 1,100 base + 15.00 LF French Drain 12.30 IF Mid -tank Access Riser, 36' 700.00 Each Pond Overflow Spillway 4.70 SY Restrictot/08 Separator, 12' 785.00 Each Restricta/08 Separator, 15' 885.00 Each Restr ctor/08 Separator, 18' 1,035.00 Each SUBTOTAL FOR PA" barer latae - 1 =AM Page 6 RID FACILITIES AND `. CONVEYANCE:.;..::. SYSTEMS ...:.:.; :..• Sierra Project No. SONO REDUCTIONS Ounnahs Coa.plete DRAINAGE (Con't.l Biprap. placed Tank End Reducer Trash Rack 12' Trash Rack, 15' Trash Rade, 118' Trash Rack, 21' 400.00 Each 180.00 Each 185.00 210.00 240.00 Each Each PARKING LOT SURFACING t.. counts rock & 2.5- base course 4' ,elect borrow W ITE4N ITEMS 1.75 sY .111F..•M PO .- IMMr SUBTOTAL (SUM ALL PAGES): 30% CONTINGENCY & MOBILIZATION: TOTAL Page 7 154.j 9i8.10 ,43 3.5� 10)3)3,10 ,0 31095.0 13414.57(A) (8) ICI Sierra .. _,__. No. Quantities above were completed by: Signature: Date: PE Registration Number: Telephone Number: (z(4) -gef S ?570 Firm Name: WAStt)FXTart) 1.AWIO 19ES/6 4.1 Address: /0300 NtiEr_'t0/kr-) 4-VE_ /l.1• 4 it 3 .56 4-rn E w,q 98/ 33 This section to be completed by King County BONG COMPUTATIONS: • Stabilization/Erosion Sediment Control (ESC) Existing Right -of -Way Improvements Future Public Road I--,provements Private Improvements R/D Facilities and Conveyance Systems TOTAL PERFORMANCE BOND AMOUNT RIGHT-OF-WAY & SITE RESTORATION BOND (First 57,500 of bond shall be cash.) PERFORMANCE BOND TOTAL AFTER BOND REDUCTIONS (T -A,8 OR C) PER ORMANCE BOND AMOUNTS (D) Zi O 7 (E) (F) 8 —793. S3 l3; */ 4.57 mOlet.Z.860 (D+E) 01 02 '3 2,078 MAINTENANCE BOND AMOUNT (E+F)x0.25 = DEFECT BOND AMOUNT x0.15 - NOTE: The word 'bond' is used to represent Original bond computations Signature of Person Preparing Bond Reduction any financial guarantee acceptable to prepared by: Date: King County. IY.......eU - :nolo . Page 8 01 02 /3 Date Date Date NOTE: Total bond amounts remaining after reduction shell not be cess then 30% of the original amount or the sum of the maintenance and defect amounts shown above. whichever 1s greater. SECTION XI Maintenance and Operations Manual Maintenance and Operations Manual A maintenance and operations manual will be provided prior to occupancy. APPENDIX BP SERVICE STATION RETAIL DEVELOPMENT SURFACE WATER TECHNICAL INFORMATION REPORT Tukwila, Washington Prepared for: Roger 011enburg/Architect 515 116th Avenue NE, Suite 202 Bellevue, VA 98004 Prepared by: David Evans and Associates, Inc. 415 -118th Ave SE Bellevue, WA 98005 OEVT-0005 December, 1996 ), DAVID EVANS AND ASSOCIATES, ADDENDUM BP SERVICE STATION RETAIL DEVELOPMENT SURFACE WATER TECHNICAL INFORMATION REPORT Tukwila, Washington Prepared by: David Evans and Associates 3209 Rockefeller Avenue Everett, WA 98201 Date: March 24, 1997 Section II1 Downstream Analysis has been amended with the following information 1. The existing outfall from the site via a 6" pipe at the northeast corner of the site was found not to discharge to the existing ditch along the west side of the Union Pacific railroad embankment. Site Runoff is discharged to a 4" perforated pipe which is failing. Existing surface patterns naturally flow to the east and to the existing ditch along the railroad embankment. 2. Runoff from the site will be discharged via a 12" pipe connecting to catch basin no. B-3 of the Northwest Expo Center and conveyed to the north by the construction of a new piped system and ditch improvements. Plans for this new system have been previously approved by the City of Tukwila Public Works for the Northwest Expo Center as shown on sheets S-14 and S-15. ththtdwlmg till jests mals ... Ont.tdnJinl (h3iility INC. 3209 Rockefeller Avenue Everett, Washington 982oi Tel: 206.259.4099 Fax: 206.259.3230 ,AEN B FR SITIAI■ �'" BP SERVICE STATION RETAIL DEVELOPMENT DRAFT SURFACE WATER TECHNICAL INFORMATION REPORT Tukwila, Washington Prepared for: Roger 011enburg/Architect 515 116th Avenue NE, Suite 202 Bellevue, WA 98004 Prepared by: David Evans and Associates, Inc. 415 -118th Ave SE Bellevue, WA 98005 OEVT-0005 December, 1996 TABLE OF CONTENTS Page # SECTION I Overview 1 SECTION II Preliminary Conditions Summary 5 Core Requirements 5 Special Requirements 5 Sensitive Areas Ordinance Requirements 6 SECTION III Off Site Analysis 9 DOWNSTREAM ANALYSIS 9 SECTION IV Water Quantity and Quality Control 11 SECTION V Conveyance System Analysis and Design 13 SECTION VI Special Reports and Studies 15 SECTION VII Basin and Community Plan Areas 16 SECTION VIII Other Permits 17 SECTION VIII Other Permits 17 SECTION IX Erosion and Sedimentation Control Design 21 SECTION X Bonds 19 SECTION XI Maintenance and Operations Manual 20 Conventions and Abbreviations 21 Definitions 22 Tables and Figures Figure 1 - Technical Information Report Worksheet 2 Figure 2 - Vicinity Map 4 Figure 3 - Drainage Basins and Site Characteristic's 7 Figure 4 - Soils Map 8 Precipitation values 11 Site Subbasin and Hydrologic Data 11 Figure 5 - Site Pian, Facility Improvement Map 14 . SECTION I Overview This Storm Water Technical Report (TIR) provides storm water requirements and design calculations for the new BP Service Station Retail Development in Tukwila, Washington. The project is located at 16200 West Valley Highway, in the Green River Basin, Section 25, Township 23 North, Range 4 East (see Figure 2). The project consists of developing a new service station with underground tanks and overhead canopy, a convenience store building, a conveyor system car wash,. paved circulation and parking areas, and landscape planters. Proposed frontage improvements along West Valley Highway include curb, gutter and a 6' sidewalk and a storm drain system. The area is primarily commercial. The site is bordered by a hotel to the north, a restaurant to the south, the Union Pacific Railroad to the east, and West Valley Highway to the west., The site is relatively flat, sloping gently to the northeast. EXISTING DRAINAGE SYSTEM AND PROBLEMS The existing site consists of a restaurant building and asphalt paved parking area with landscaped planters. Existing site runoff is collected in two catch basins located near the middle of the parking lot. Flow is conveyed via a 6" pipe and an 8" pipe to the west edge of the property where it is • discharged. Off-site flow along the West Valley Highway sheet flows to the large vegetated depression located near the northwest corner of the site. PROPOSED DRAINAGE SYSTEM The drainage system will consist of catch basins and a closed pipe system that discharges on-site flows to a biofiltration swale that will discharge to the existing catch basin and pipe at the northeast corner of the site. This pipe discharges flow to the existing ditch on the east edge of the property. Runoff from frontage improvements to West Valley Highway will be collected in catch basins and conveyed via a pipe system to the depression at the northwest corner of the site. VARIANCES and EXCEPTIONS The proposed drainage system is designed to meet the 1990 Surface Water Design Manual and no variances are necessary. Overview 1 VICINITY MAP FIGURE 2 SECTION II Preliminary Conditions Summary This section will address the requirements set forth by the King County Surface Water Management Design Manual Core and Special Requirements listed in Chapter 1. King County Surface Water Management Design Manual Core Requirements 1. Discharge at a natural location (1.2.1): Flow from the site currently discharges to the east via two pipes. The developed site will discharge via the catch basin at the northeast corner. 2. Off-site Analysis (1.2.2): A level 1 downstream analysis was performed for the downstream tributary. A complete summary of the off-site analysis can be found in Section III. 3. Runoff Control (1.2.3): A. Peak Rate Runoff Control: No detention will be provided as this project does not increase the flow in the 100 year event by 0.5 cfs or more. The site is currently paved, and the developed condition will not increase impervious area significantly. B: Biofiltration: Biofiltration facilities have been designed to meet DOE water quality requirements for site impervious surfaces subject to traffic through the use of a swale. 4. Conveyance Facilities (1.2.4): Closed pipe systems used to convey on-site runoff will be designed to carry the 25 -year event flow and provide a minimum of 0.5 feet of freeboard between the hydraulic grade line and the top of the structure. 5. Erosion/Sedimentation Control Plan (1.2.5): Erosion control measures are outlined in Section IX. 6. Maintenance and Operation (1.2.6): Maintenance and Operations are covered in section X. No special maintenance will be necessary. 7. Bonds and Liability (1.2.7): This issue is covered in section XI. King County Surface Water Management Design Manual Special Requirements 1. Critical Drainage Areas (1.3.1): This project does not lie within a critical drainage area. 2. Compliance with an Existing Master Drainage Plan (1.3.2): The project is located within the Tukwila Nelson Place/Longacres Way Sub -basin which lies within the Green River Basin. This project complies with improvements identified in the Tukwila Nelson Place/McLeod/Boeing CSTC Storm Drainage Study Technical Report. 3. Conditions Requiring a Master Drainage Plan (1.3.3): The project does not require a master drainage plan. Conditions Summary 5 4. Adopted Basin or Community Plans(1 .3.4): The project drainage report and plans were prepared in conformance with the City of Tukwila Surface Water Standards Ordinance No. 1755 and King County Green River Basin Plan. 5. Special Water Quality Controls (1.3.5): The project will not increase impervious area subject to vehicular use by one acre or more the drainage basin. Therefore, no special water quality controls are required. 6. Coalescing Plate OiI/Water Separators (1.3.6): The project will not increase impervious area subject to vehicular use by five acres or more within a given drainage basin. Therefore, no coalescing plate oil/water separators are required. 7. Closed Depressions (1.3.7): The project is not tributary to a closed depression. 8. Use of Lakes, Wetlands or Closed Depressions for Peak Rate Runoff Control (1.3.8): The project will not use a lake, wetland or closed depression for peak runoff control. 9. Delineation of 100 Year Floodplain (1.3.9): The project is not located within any FEMA designated floodplain. 10. Flood Protection Facilities for Class 1 and 2 Streams (1.3.10): There are no Class 1 or 2 streams within the project area, therefore, no flood protection facilities are proposed. 11. Geotechnical Analysis and Report (1.3.11): The Geotechnical Analysis for the site has not yet been completed, and will be included in the final TIR. 12. Soils analysis and report (1.3.12): The soils underlying this project have been mapped by the United States Department of Agriculture Soil Conservation Service. The maps, issued in November, 1973, identify the soils as "Urban," which is classified as a variable soil type. Sensitive Areas Ordinance Requirements According to the Sensitive Areas Map Folio, there are no sensitive areas located within or adjacent to this project. Conditions Summary 6 Figure 3 - Drainage Basins a.... Site Characteristic's - Show tributary boundaries, location of outfalls and indicate future outflow, detention and water quality facilities, show and indicate longest length of travel to R/D facility, 500 foot stationing, streams, wetlands Conditions Summary 7 O 6 MI TO IN7EPS7A7! J I •� 1BM� elAythieelc lata -d'; hommir eec v ��% _ `i;� I asr / .� ' =e. 91. � PerkEIENNielglirt � IP:447 �I sw9iiiiivalAIR J ' iii% 1� �m�' IP uR• ''_,• / 11 , AgC Substa; A, 20 '7'30" Ne ljo1�.5 MAN SECTION III Off Site Analysis This section identifies the tributary basin areas upstream of the project site, and evaluates upstream and downstream.drainage system problems. The intent of this section is to demonstrate the proposed project will neither aggravate existing problems or create new drainage problems. DOWNSTREAM ANALYSIS Standard Requirements (based on Design Manual and SAO) 1. Analysis shall extend to a point where the project site constitutes no more then 15% of the basin but in no case less then 1/4 mile (1.2.2-1). 2. Level 1 Analysis shall show on a map downstream pipe sizes, channel characteristics and a narrative of problems (1.2.2-2) 3. Level 2 Analysis is required if it is found there is a lack of capacity; overtopping, scouring, bank sloughing, or sedimentation; flooding of structures, road access, or septic fields; significant destruction of aquatic habitat. Analysis shall be performed at each problem site for the 2, 10, and 100 year events; using mannings equation and with tape and hand level measurements. Evaluate problem for existing and proposed conditions. (1.2.2-3) 4. Level 3 Analysis is require where the proposed project site constitutes 15% of the flow. Analysis must be done using licensed survey and standard step back water methods (1.2.2-2) 5. Solution of Problem - It must be shown that either the project will neither aggravate an existing problem or cause a new one. Where the project will aggravate a problem then mitigation must be provided. (1.2.2-3) 6. Discharge at Natural location is required and produce no significant impacts to the downstream property (1.2.1-11. Special Requirements (based on P -suffix, basin or community plans, and critical designations) None Upstream Analysis There are no upstream basins tributary to the site. Runoff from West Valley Highway will continue to discharge to the large vegetated depression located near the northwest comer of the site. It appears this depressed area is connected with a pipe to a depressed area directly across West Valley Highway. However, no pipe was found due to the thick vegetation. The depressed area on the west side of West Valley Highway then drains directly to the Green River. Level 1 Downstream Analysis Field Inspection A field review was performed for the subject property by David Evans and Associates, on Tuesday morning, December 24, 1996. The weather was overcast with a temperature of approximately 40 degrees. The results of the field review are noted below. No problem areas were identified that needed to be specifically looked at for assessment. Drainage System Description and Problem Screening Level 1 - Field review Runoff from the site will be discharged via the existing 6" pipe connected to the catch basin located at the northeast corner of the site. This pipe discharges to the existing ditch located Off Site Analysis 9 along the west side L. the Union Pacific railroad embankment a..a flows north for approximately 1;000 feet. The ditch has a bottom width of 3 to 4 feet, 3 feet of available depth with 3:1 side slope to the west and 2:1 side slope to the east. A 24" corrugated black plastic pipe picks up the flow from the ditch behind the.Embassy Suites parking lot and conveys it north for approximately 150 feet. An 50' long open ditch section, approximately 4' wide at the bottom, 2' high with 3:1 side slopes carries flow from the 24" pipe to another section of 24" corrugated black plastic pipe. This pipe is roughly 30 feet long and ties into a drainage structure at S 158th Street. At this point.a 4'-8" x 1'-10" high box culvert provides the east -west conveyance from S 158th Street to the BNSF Burlington Northern Railroad tracks. The analysis was terminated at the railroad tracks which is over 1/4 mile from the discharge point of the BP Service Station. The ditch along the Union Pacific Railroad did not show signs of overtopping or erosion. According to the Nelson Place/McLeod Boeing CSTC Storm Drainage Study the 24" pipe at Embassy Suites and the box culvert on S 158th Street were sized to accommodate flow from the entire sub -basin which includes the proposed BP Service Station site. There are no signs of erosion at the pipe intakes or outfalls. Level 2 and Level 3 analysis were not performed for the project, and additional review of the downstream drainage does not appear to be warranted. Mitigation Mitigation includes providing water quality treatment for the impervious surface area subject to vehicular traffic. Water quality will be provided in an on-site biofiltration swale. Off Site Analysis 10 SECTION IV Water Quantity and Quality Control SITE HYDROLOGY (parts A & B) Calculations for this section are contained in the appendix. Precipitation values used in Hydrologic Analysis (in/24-hours) • Part 2yr 10yr 25yr 100yr 2.0" 2.9" 3.4" .9" 3.9"- Part A - Existing Site Hydrology The majority of the existing site hydrology is building and pavement areas with landscaped planters. Flow from the site is collected in catch basins and discharged via a pipe system to the east side of the site. Part B - Developed Site Hydrology The developed site hydrology includes construction of a paved parking and circulation area for a service station, car wash and convenience store with landscaped areas. The roof area for the car wash, building and canopy is 11,184 SF (0.26 Ac) and is discharged to the sanitary sewer system. The developed site impervious area subject to vehicular traffic is 27,450 SF (0.63 Ac). Site Subbasin and Hydrologic Data, (Area in acres, Tc in Minutes) Existing Proposed Basin Area CN Imp. Area Tc Pery Area CN Imp. Area Tc 0.11 85 0.99 8.97 0.21 85 0.89 8.43 The new drainage system will collect surface runoff in catch basins and carry the water via underground pipes to a biofiltration swale located at the northeast corner of the site. PART C - DETENTION PERFORMANCE REQUIREMENTS Standard Requirements (based on Design Manual and SA01 2. 3. 4. 5. Flow rate must release flow at or below existing 2 and 10 year peak rates, the volume to reduce flow to these rates will be increased be 30%. The system will then be evaluated at the 100 year level and if adverse impacts occur addition mitigation may be required (1.2.3.2&3). Existing condition are those that were present in May 1979 (1.2.3-1) Detention ponds are to be open ponds unless there is no practicable alternative and may be combined with wetponds (1.2.3-3) Retention facilities must be evaluated for the 7 day 100 year event and downstream over flow path evaluated (1.2.3-4) (1.3.7-1). Wetland shall not be used for detention unless there is no alternative, it is a type 3 wetland with its only major function is storage, and the facility is regional in nature. 154(91.C)1 Flow control is not required if there is less than 5,000 s.f. of new impervious surface, flow increase is less than 0.5 cfs for the 100 year event, or discharges to the Cedar, Green, Duwamish, Sammamish, Skykomish, Quantity and Quality 11 Snoqualamie, White or Si , rivers; or Lake Sammamish or Washington; or to jet Sound (1.2.3-5). Flow control is also not required if -discharging to a lake, wetland, or closed depression if the increase of floodplain is less than 0.1 feet and permission is secured form affected property owners, water quality treatment is provided before discharge, and if there is an outlet it may need to modified to retain existing 2, 10, and 100 year flow rates (1.3.8- 1) 6. Bypasses may be permitted is discharge is to the same subbasin and flow rate is compensated for at the detention facility (1.2.3-6) 7. Off -sits flow greater than 50 percent of the 100 year on-site flow must be carried in a separate system around the detention facility (1.2.3.6) Special Requirements (based on P -suffix, basin or community p/ans, and critica/ designations) None, see preliminary conditions, section II. PART D - WATER QUANTITY CONTROL As can be seen in the calculations in the appendix, the flow from the site in the proposed condition will not increase by 0.5 cfs in any of the three major design storm events. The flow rates are as follows. Existing Flow (cfs) Developed Flow (cfs) 2yr 10yr 100yr 2yr l0yr 100yr 0.47 0.72 0.85 0.45 0.69 0.82 Based on these findings, no peak rate runoff control is proposed for the site. WATER QUALITY Standard Requirements (based on Manual) There are four levels of water quality facilities defined in the 1990 Surface Water design Manual, each level is additive and they do not overlay or replace lower level facilities. These levels are as follows: 1. OiI/Water Separation - required in all pipe conveyance systems serving paved areas. (1.2.4-3) 2. Biofiltration Facility - required in addition to Oil/Water Separation when the new impervious area subject to vehicular use•exceeds 5000 s.f. (1.2.3-1) 3. Water Quality Pond - required in addition to the biofiltration facility when the new impervious area subject to vehicular use or chemical storage exceeds one acre. (1.3.5) 4. Coalescing Plate Separators - required in addition to Water Quality Pond if there are 5 acres or more of new impervious surface subject to any of the following: 2500 ADT, chemical or petroleum storage, heavy equipment use. (1.3.6) Special Requirements (based on P -suffix, basin or community p/ans, and critica/ designations) None, see section II Due to the fact that impervious area on the site that is subject to vehicular use is being cut in half, this site is not subject to standard requirements for water quality. However, the proposal calls for the installation of a biofiltration swale for the parking lot and circulation area. Sizing of this facility is based on the 6 -month storm event. See the appendix for sizing calculations for this facility. Quantity and Quality 12 SECTION V Conveyance System Analysis and Design Standard Requirements (based on Design Manua/ and SAO) 1. Facilities must convey 100 year flow without overtopping crown of roadway, flooding buildings, and if sheet flow occurs it must pass through a drainage easement. (1.2.1-3) 2. New pipe systems and culverts must convey the 25 year flow with at (east 0.5 feet of freeboard. (1.2.4-1) 3. Bridges must convey the 100 year flow and provide a minimum of 2 feet of varying up to 6 feet of clearance based on 25% of mean channel width. (1.2.4-2)(4.3.5-6) 4. Drainage ditches must convey the 25 year flow with 0.5 fent of freeboard and the 100 year flow without overtopping. (1.2.4-2) 5. Floodplain Crossings must not increase the base flood elevation by more than 0.01 feet (41(83.C11 and shall not reduce the flood storage volume 137(82.A) 41(83.A)]. Piers shall not be constructed in the FEMA floodway. (41(83.F.1)I 6. Stream Crossings shall require a bridge for class 1 streams that does disturb the stream bed or banks. For type 2 and 3 stream open bottom culverts or other methods may be used that will not harm the stream or inhibit fish passage. 160(95.8)1 7. Discharge at Natural location is required and produce no significant impacts to the downstream property (1.2.1-1). Special Requirements (based on P -suffix, basin or community plans, and critical designations) None The Facility Improvement Map at the end of this section shows a schematic of proposed improvements. Detailed information and calculations are contained in the appendix. OFF-SITE CONVEYANCE There is no off-site conveyance. ON-SITE CONVEYANCE The design of both open channel and closed conduit systems are based on the Rational Formula Methodology. Because the SBUH hydrology method uses rainfall information developed on hourly averages, the Rational formula has been used to develop peak flow rates for conveyance facilities where the time of concentration is less than 30 minutes. Although the Rational Formula make many simplifying assumptions it's rainfall data base is more closely related to smaller times of concentration. Peak flows developed for impervious surface using the rational formula, with times of concentration less then 30 minutes are more conservative then those using the SBUH method. Calculations showing the sizing of the system are included in the Appendix. Conveyance System 13 Figure 5 - Site Plan, Facility ....provement Map - show location and siz.,.g of conveyance, crossings, R/D, and water quality facilities. Conveyance System 14 SECTION VI Special Reports and Studies Sensitive areas within, adjacent, or significantly affected by a project shall require a special study unless there is a substantial showing that the project will not affect the area contrary to the goals of the Sensitive Area Ordinance 9614 18(511. There are no special reports or studies for this project. Special Reports 15 SECTION VH Basin and Community Plan Areas BASIN PLAN (1.3.4-1) The project lies within the City of Tukwila South CBD Basin Plan. The drainage report and plans were prepared in conformance with the basin plan and the requirements outlined in the City of Tukwila Storm Drainage Ordinance No. 1755. COMMUNITY PLAN (1.3.4-1) The project does not lie within an identified Community Planning Area. The plans were prepared in conformance with the City of Tukwila development standards. MASTER DRAINAGE PLAN (1.3.2-1) This project does not require a Master Drainage Plan. CRITICAL DRAINAGE AREAS (1.3.1-1) This project does not lie within an identified Critical Drainage Basin. Basin and Community Plan 16 SECTION VIII Other Permits Permits required for this project include: CLEARING AND GRADING PERMIT, City of Tukwila Other Permits 17 SECTION IX Erosion and Sedimentation Control Design Standard Requirements (based on Design Manua/ and SAO) Erosion/Sediment Control Plan shall include the following: 1. Facilities required include; rock quarry pad construction access, sedimentation pond, and filter fabric fencing in smaller areas (1.2.5-1) 2. Timing - For the period between November 1 through March 1 disturbed areas greater than 5,000 s.f. left undisturbed for more than 12 hours must be covered with mulch, sodding or plastic covering. A construction phasing plan shall be provided to ensure that control measures are installed prior clearing and grading (1.2.5-1). 3. Planning - Plan shall limit tributary drainage to an area to be cleared and graded. Delineate dimension, stake, and flag clearing limits (1.2.5-1). 4. Revegetation - Revegitate areas to be cleared as soon as practicable after grading. (1.2.5-1) Special Requirements (based on P -suffix, basin or community plans, and critical designations) DRAFT Erosion control measures will include silt fences, straw check dams, catch basin inlet protection and ground cover practices. Silt fences will be placed at the downstream edges of all disturbed areas. The plans ill include details and notes for the use and maintenance of straw check dams, catch basin protection and ground cover. practices. DRAFT Erosion and Sediment Control 18 SECTION X Bonds The bond quantity worksheet will be included in the appendix of the final TIR. Bonds 19 SECTION XI Maintenance and Operations Manual DRAFT, NOT INCLUDED AT THIS TIME STANDARD MAINTENANCE Facilities will be maintained by standards set forth in the King County Surface Water Design Manual. SPECIAL MAINTENANCE None Maintenance and Operations 20 Conventions and Abbreviations Reference Conventions Use of brackets (1 indicates reference to the Sensitive Areas Ordinance; (page#(section#)) Use of () indicates reference to the Surface Water Design Manual; (section# -page#) Abbreviations Ac - Acres CF - Cubic feet CFS - Cubic feet per second COE - United States Army Corp of Engineers DDES - King County Department of Development and Environmental Services DOE - Washington Department of Ecology EPA - United States Environmental Protection Agency FEMA - Federal Emergency Management Agency FIRM - Flood Insurance Rate Map FPS - Feet per second SF - Square feet SWM - King County Surface Water Management TIR - Technical information report Tc - Time of concentration WDF - Washington Department of Fisheries WDW - Washington Department of Wildlife Conventions and Abbreviations 21 Definitions Base flood - 100 year event, 1% chance of occurring in a given year. (17(21)] Compensating Storage - equivalent storage, providing equal volume at 1 foot increments. [19(29)1 Flood Hazard Area - Areas flooded during base flood associated with streams, rivers, lakes, wetlands, and closed depressions.(21(37)1 Landslide Hazard Area - 15% slope with silt or clay soils and have ground water seepage; or areas showing movement since the Holocene epoch (10,000 year ago); or unstable area adjacent to rapid stream incision or erosion; area on an alluvial fan that may inundated by debris flow. 144(47)1 Steep Slope Hazard Area - inclination of 40% within a vertical change of 10 feet or more. 129(68)1 Stream - (30(69)1 Class 1, inventoried as shorelines of the State; Class 2, streams that flow year around or are used by salmonids; Class 3, intermittent or ephemeral during years of normal rainfall. Drainage and irrigation ditches shall not be considered streams unless the are used by salmonids. Wetlands - (32(75)1 Class 1, Unique and Outstanding rating #1, supports endangered or threatened species, 40% open water with two classes of vegetation, greater then 10 acres with 3 classes of wetland including open water, presence of infrequent plant associations; Class 2, Significant rating #2, greater than 1 acre, less than 1 acre with 3 or more wetland classes or classified as forested wetland, contains heron rookeries or raptor nesting sites; Class 3, Lesser concern rating #3, less than 1 acre with up to 2 wetland classes; Where vegetation has been removed an area may be classified as a wetland if there is presence of hydric soil with documentation of previous existence of a wetland. Zero Rise Floodway - Floodway necessary to contain base flood without causing a rise of greater than 0.01 feet. Boundary of floodplain on Flood Insurance studies shall be considered as boundaries of zero rise floodway. [22(37.D)] Definitions 22 EXISTING AND PROPOSED HYDROLOGY iPOc, Oil (.,6�,j /9-.-6/4 . 8, SuvthCfnfei ,� X/ S%int C on(i.A./of7 OE yr GYXJS C Rose. l z/, 8/96 r0tGl S, tc /i.;. = 47, 998 sF /./G AG.) • (163YT) * (/-6)05)+(/2'X/g') * (1)(200) (m)(115) t (35 .)(6).)* 0 po')(s ") = ¢BG3 SF (O / i Atc ) �m��iv Jus /4 '4A - / /0 - D // 44. = 0.99 fie.- • /`a 0//Crov ▪ f%/cit. dt� ,Sov//,C!, =,!i OEVT DOG C /L//8/ 9c Pio/) arc/ (ond, �/7 Apra. ' ( �Z (202 5 + /95'),`( l'z(2/6 . 2e,9')) = 998 .SF (/./o /4c) Per, ov1 - L ./• is<<,.0 e flus 9'/ 3 2 Sf (0. 2/ /1-G • "14 — 0. 2 / ft4. = D..5 9 , . Roo' N.•A f7/ /on�.� 19n✓rni.nu lfy/• An el Cai w4SA is ':un Jv% Or ,i►lp cpv, UVJ ami`. /o i-4/ k, WG 4/4 li yPJ /(61G/7-771.$ (� Canopy - (45)C40j) .' (92 '.143 ) rGn i (, c( 5 rc (52./ 41') CU/ 144,17' (30'X8o') f (1'% o.) • 5,75( (o /3 f}4..) • 1,288 (0.05 flc.) /9C (0.0 7- 4-c.) //1 / 3-9 (o. Z Ac) -Tan �si.r:v� pi�A Sa..r ILO r/oi hsa/.,� D• 3 ? �k - 0.26 A -c = 0 Gs ft G • ,12/23/96 3:18:3. )m David Evans & Associate. Inc - Bellevue page ]_ .BP SERVICE STATION RETAIL DEVELOPMENT WATER QUANTITY CALCULATIONS BASIN SUMMARY BASIN ID: Al NAME: 2 -YEAR EXISTING SBUH METHODOLOGY TOTAL AREA 1.10 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE KC24HR PERV IMP PRECIPITATION 2.00 inches AREA..: 0.11 Acres 0.99 Acres TIME INTERVAL 10.00 min CN 85.00. 98.00 TC 5.00 min 8.97 min ABSTRACTION COEFF: 0.20 impTcReach -Sheet L: 180.00 ns:0.0110 p2yr: 2.00 s:0.0100 impTcReach - Channel L: 155.00 kc:42.00 s:0.0070 PEAK RATE: 0.47 cfs VOL: 0.15 Ac -ft TIME: 480 min BASIN ID: A2 NAME: 10 -YEAR EXISTING SBUH METHODOLOGY TOTAL AREA 1.10 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE KC24HR PERV IMP PRECIPITATION 2.90 inches AREA..: 0.11 Acres 0.99 Acres TIME INTERVAL 10.00 min CN • 85.00 98.00 TC 5.00 min 8.97 min ABSTRACTION COEFF: 0.20 impTcReach - Sheet L: 180.00 ns:0.0110 p2yr: 2.00 s:0.0100 impTcReach - Channel L: 155.00 kc:42.00 s:0.0070 PEAK RATE: 0.72 cfs VOL: 0.23 Ac -ft TIME: 480 min BASIN ID: A3 NAME: 100 -YEAR EXISTING SBUH METHODOLOGY TOTAL AREA 1.10 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE KC24HR PERV IMP PRECIPITATION 3.90 inches AREA..: 0.11 Acres 0.99 Acres TIME INTERVAL 10.00 min CN 85.00 98.00 TC 5.00 min 8.97 min ABSTRACTION COEFF: 0.20 impTcReach - Sheet L: 180.00 ns:0.0110 p2yr: 2.00 s:0.0100 impTcReach - Channel L: 155.00 kc:42.00 s:0.0070 PEAK RATE: 0.99 cfs VOL: 0.32 Ac -ft TIME: 480 min 12/23/96 3:184-34 pm David Evans & Associates Inc - Bellevue page 2 BP SERVICE STATION RETAIL DEVELOPMENT • WATER QUANTITY CALCULATIONS BASIN SUMMARY BASIN ID: A4 NAME: 2 -YEAR DEVELOPED SBUH METHODOLOGY TOTAL AREA 1.10 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE KC24HR ' PERV IMP PRECIPITATION 2.00 inches AREA..: 0.21 Acres 0.89 Acres TIME INTERVAL.....: 10.00 min CN 85.00 98.00 TC 5.00 min 8.43 min ABSTRACTION COEFF: 0.20 impTcReach - Sheet L: 150.00 ns:0.0110 p2yr: 2.00 s:0.0080 impTcReach - Channel L: 100.00 kc:42.00 s:0.0070 PEAK RATE: 0.45 cfs VOL: 0.15 Ac -ft TIME: 480 min BASIN ID: A5 NAME: 10 -YEAR DEVELOPED SBUH METHODOLOGY TOTAL AREA 1.10 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE KC24HR PERV IMP PRECIPITATION 2.90 inches AREA..: 0.21 Acres 0.89 Acres TIME INTERVAL 10.00 min CN 85.00 98.00 TC 5.00 min 8.43 min ABSTRACTION COEFF: 0.20 impTcReach - Sheet L: 150.00 ns:0.0110 p2yr: 2.00 s:0.0080 impTcReach - Channel L: 100.00 kc:42.00 s:0.0070 PEAK RATE: 0.69 cfs VOL: 0.22 Ac -ft TIME: 480 min BASIN ID: A6 NAME: 100 -YEAR DEVELOPED SBUH METHODOLOGY TOTAL AREA 1.10 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE KC24HR PERV IMP PRECIPITATION 3.90 inches AREA..: 0.21 Acres 0.89 Acres TIME INTERVAL 10.00 min CN • 85.00 98.00 TC 5.00 min 8.43 min ABSTRACTION COEFF: 0.20 impTcReach - Sheet L: 150.00 ns:0.0110 p2yr: 2.00 s:0.0080 impTcReach - Channel L: 100.00 kc:42.00 s:0.0070 PEAK RATE: 0.96 cfs VOL: 0.31 Ac -ft TIME: 480 min .,12/20/96 2:47:4_ dm David Evans & Associate Inc - Bellevue page 1 -BP SERVICE STATION RETAIL DEVELOPMENT WATER QUALITY CALCULATIONS _ BASIN SUMMARY BASIN ID: Al NAME: 6 -MONTH EVENT SBUH METHODOLOGY TOTAL AREA 0.84 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE KC24HR PERV IMP PRECIPITATION.,...: 1.33 inches AREA..: 0.21 Acres 0.63 Acres TIME INTERVAL 10.00 min CN 85.00 98.00 TC 5.00 min 8.43 min ABSTRACTION COEFF: 0.20 impTcReach - Sheet L: 150.00 ns:0.0110 p2yr: 2.00 s:0.0080 impTcReach - Channel L: 100.00 kc:42.00 s:0.0070 PEAK RATE: 0.20 cfs VOL: 0.06 Ac -ft TIME: 480 min BASIN ID: A7 NAME: 100 -YEAR EVENT SBUH METHODOLOGY TOTAL AREA 0.84 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE KC24HR PERV IMP PRECIPITATION 3.90 inches AREA..: 0.21 Acres 0.63 Acres TIME INTERVAL 10.00 min CN 85.00 98.00 TC 5.00 min 8.43 min ABSTRACTION COEFF: 0.20 impTcReach - Sheet L: 150.00 ns:0.0110 p2yr: 2.00 s:0.0080 impTcReach - Channel L: 100.00 kc:42.00 s:0.0070 PEAK RATE: 0.72 cfs VOL: 0.23 Ac -ft TIME: 480 min PROJECT: DESCRIPTION: BEGIN LOCATION: END LOCATION: LENGTH CHANNEL DESIGN FORM BP Southcenter Biofiltration Swale 200 LF I FREEBOARD DEPTH (FT) WATER DEPTH (FT) (SIDE SLOPE 1 = (1/H) SIDE SLOPE 2 = (1/H) BOTTOM WIDTH IN FEET IMANNINGS VALUE 'LOPE OF CHANNEL FT/FT Input Output f = Y = H1 = H2 = b = n = s = 1 0.33 3 3 1.7 0.35 0.02 Velocity = Flow, CFS = Top Width = 0.23 0.20 9.68 The above indicates the design for biofiltration function for the 6 -month event. r DCS i jr WGte r Svr `CCG 1I.7'.. z (s )1 (Zoo) 1.o 5F viv6'ltnf MFcr Jv��aCG loo' O 54' So J 7 ZS FrcE x ci 0.7ih:0.3 fi .7 7 TYPICAL SECTION PROJECT: CHANNEL DESIGN FORM BP Southcenter DESCRIPTION: Biofiltration Swale BEGIN LOCATION: END LOCATION: LENGTH 200 LF 'FREEBOARD DEPTH (FT) WATER DEPTH (FT)• 'SIDE SLOPE 1 = (1/H) SIDE SLOPE 2 = (1 /H) BOTTOM WIDTH IN FEET I MANNINGS VALUE "LOPE OF CHANNEL FT/FT Input Output f = 1 Y = 0.33 H1 = 3 H2 = 3 b = 1.7 n = 0.04 s = 0.005 Velocity = Flow, CFS = Top Width = 1 .00 0.89 9.68 The above indicates the swale conveyance and stability calculations. The actual swale slope and Mannings "n" value are used. The swale has the capacity to conveys the 100 -year design flow of 0.72 cfs and maintain a freeboard of 1 foot with a velocity of Tess than 1.5 ft/sec. TYPICAL SECTION CONVEYANCE CALCULATIONS DCv T coos • t'o1.-- /e0 c, O//� n /c,, S "?-cc A • / / 13P SU�fh (Cnj'c' /2/2, 3/96 (oni(UGi'(c (4. /CS _1174.7,1 G / til.thod /((4 (4 ) _ 1. / 44, cs We/4A , prp 115 = Z•/5 lice = 2.45 Qzs" c -TA f/vo ' e T i9 c _7- (0• Y.50) + (o.3 ,4X90) /./0 = 0.82 cFrom - e& fT/, - or cam, /e, � ' 5. 4. M,q • 0.'92(2•/7 ,Y/•/ 2.0/ cits 0. 82 (24;Y/./) 2. 2/ cis A.Ssc,me 5 // jt ur, J'., -r p,( � /2 " conC,e , S. = 0..c. n.. 0/3 1.49 _,92 z/, 5 ,L _ 1,49 0/3 (.7.957.z.5)Z�3005)L = 2.5( (ls A - z(591 o. 73- 2 5/ c'/s 7 2.o/ (is 2 2/ c/s sA- A .i85 /' zr, 'Z5 �►~ Transportation and Traffic Engineering PLANNING • DESIGN MEMORANDUM TO: Brian Shelton DATE: The City of Tukwila The Transpo Group November 6, 1997 RECEIVED CITY OF TUKWILA OV E 157 FROM: Tasha Leshefka TG: 97316.00 The TRANSPO Group, Inc. PERMIT CENTER SUBJECT: TRIP GENERATION ANALYSIS - PROPOSED WENDY'S RESTAURANT The purpose of this memorandum is to summarize the anticipated trip generation characteristics and potential impacts of the proposed Wendy's Restaurant on West Valley Highway in the City of Tukwila. The scope of this analysis was confirmed through conversations with City officials. The following sections will summarize the project description, project trip generation, distribution and assignment, site access operations, and conclusions. Project Description The proposed Wendy's restaurant is to be located at 16200 West Valley Highway, adjacent to and sharing access with a proposed BP gas station with a convenience store and car wash. The traffic analysis for the BP station was prepared by David Evans and Associates and is provided in Attachment 1 as reference. Andy's Restaurant: a high-tumover, sit-down restaurant serving lunch and dinner was previously located on the shared BP/Wendy's project site. This restaurant has since been demolished and removed from the site. The proposed Wendy's restaurant will include approximately 2,857 sf of useable floor space with a 180 sf cold storage unit and a drive-thru window. Access to the restaurant will be provided through two driveways located along the frontage of BP on West Valley Highway. There will be two points of access between the Wendy's restaurant and the BP station. Due to the site layout, Wendy's and BP are intended to operate as a co -brand facility, which typically has a high percentage of customers using both facilities in one visit. Figure 1 shows the proposed Wendy's site plan and the adjacent BP station. Trip Generation Trip generation for the proposed Wendy's is based on an analysis conducted for a proposed Wendy's/Texaco facility in the City of Kent. Data from the ITE Trip Generation Manual is generally used as the primary basis to estimate trip generation for a proposed facility. However, co -brand facilities are relatively new to the market, and no specific data is included in the ITE Manual for such a use. One approach to estimate trip generation characteristics of a co -brand facility using The TRANSPO Group, Inc. 14335 N.E. 24th Street, Suite 201 Bellevue, Washington 98007-3737 FAX: 425/747-3688 425/641-3881 Wendy's Tukwila The TRANSPO Group, Inc. Figure 1 Site Plan Brian Shelton November 6, 1997 Page 3 The Transpo Group ITE would be to evaluate the cumulative impacts of a gasoline station and a fast-food restaurant. However, this method requires an estimation of the number of captured, or shared trips, between the two facilites. For the purposes of this study, the trip generation analysis conducted for a Wendy's co -brand facility specifically was used based on its similarity to the proposed project. The specific trip generation analysis for the Wendy's co -brand facilities collected traffic data information data from two existing McDonalds/Chevron facilities in the Puget Sound. Daily and PM peak hour traffic volumes for each site was collected through automatic traffic counters at the site driveways. Customer surveys were conducted for a two -weekday period, between the hours of 4 and 6 pm, to determine the trip types of customers. Based on the data collected, a daily rate of 528.5 trips/1,000 sf and PM peak hour trip generation rate of 40.0 trips/1,000 sf was identified for the shared facility. A copy of the trip generation analysis is provided in Attachment 2. Table 1 summarizes the total trip generation of the shared Wendy's and BP station. Since specific trip purpose data was not collected as part of the trip generation study, an estimate of Wendy's and BP's individual share of the total trip generation was made by comparing the ITE data for a fast-food restaurant (Land Use 834) and a gas station with convenience store and car wash (Land Use 846). Using this approach, Wendy's would account for approximately 40 percent of the PM peak hour trip generation, and the BP station would account for the remaining 60 percent. The same methodology was used to estimate the daily split in trip generation, which results in Wendy's accounting for 62 percent of daily trip generation and BP accounting for the remaining 38 percent. Table 1. Summary of Wendy's/BP Total Trip Generation Land Use PM Peak Hour Trips Size (sf) Daily Trips In Out Total Wendy's/BP 5,145 2,719 103 103 206 Wendy's Only 2,857 1,686 41 41 82 BP Only 2,288 1,033 62 62 124 Less Andy's Restaurant 11,200 1,992 81 64 145 Net Difference -6,055 727 22 39 61 Project impacts to the surrounding roadway system are typically based on net new trips associated with the proposed development. The trip generation shown in Table 1 represents total trip generation, which includes three types of trips: Net new, diverted, and pass -by trips. Net new trips represent trips new to the study area and site driveways as a direct result of the proposed project. Pass -by trips represent trips that are not new to the study area roadways, and use the facility as they are passing by the site. Diverted trips represent trips that are already on the study area roadways and change their route to use the facility, as part of a series of stops. To determine the anticipated impact of the proposed Wendy's/BP facility to the adjacent West Valley Highway, the number of net new and diverted trips were compared to those associated with the former Andy's restaurant. Brian Shelton November 6, 1997 Page 4 The Transpo Group The trip generation study conducted for Wendy's/Texaco in Kent revealed an average of 19 percent new trips, 7 percent diverted trips, and 74 percent pass -by trips for existing co -brand facilities. ITE data collected for a high-tumover, sit-down restaurant reveals an average rate of 28 percent new trips, 32 percent diverted trips, and 40 percent pass -by trips. Table 2 summarizes the project trip generation for Wendy's/BP in comparison to Andy's restaurant, in terms of pass - by trips and non -pass -by trips. Table 2. Summary of Wendy's/BP Project Impacts Land Use PM Peak Hour Total Trips Pass -By Trips Non Pass -By Tripsl Wendy's/BP Andy's Restaurant2 206 152 54 145 58 87 Net Difference 61 94 -33 1 Includes New and Diverted Tnps 2 Based on Table VII -1, ITE Trip Generation Manual, Fifth Edition Update, February 1995. As shown in Table 2, the proposed Wendy's/BP shared facility is anticipated to generate fewer new PM peak hour trips than the former Andy's Restaurant. The remaining 61 trips would be categorized as pass -by trips, which would impact the site driveways only and not the adjacent roadway system. It should be noted the traffic analysis prepared by DEA, Inc. for the BP station anticipated all Andy's Restaurant trips to be new trips and applied a credit of 145 PM peak hour trips rather than 87 PM peak hour trips. Thus, it can be concluded that this methodology is conservative in comparison to previous traffic studies for this site. Project Trip Distribution and Assignment Project trips, including new, pass -by, and diverted trips were assigned to the site driveways based on existing traffic patterns on West Valley Highway. Traffic data presented in the BP traffic analysis revealed traffic volumes on West Valley Highway are equally split in the north and southbound directions during the PM peak hour. Using this distribution, Figure 2 shows the PM peak hour project trip assignment associated with Wendy's Restaurant, and the total project site including the BP station. It was assumed that 80 percent of Wendy's traffic and 20 percent of BP traffic would use the south driveway, and the remaining 20 percent of Wendy's traffic and 80 percent of BP traffic would use the north driveway. Site Access Operations The level of service was calculated for the site access driveway intersections on West Valley Highway, using methodology consistent with the Highway Capacity Manual., 1994 Edition. The 21 52 97316.00 REV 11i6/97 M19T973161CAD1GRAPHIC (A) 21 52 17 23 17 23 16 22 16 22 20 51. 20 51 BP SITE WENDY'S SITE 20 51 LEGEND - WENDY'S TRAFFIC VOLUMES - BP TRAFFIC VOLUMES NOTE PROJECT TRAFFIC VOLUMES REPRESENT TOTAL TRIP GENERATION, INCLUDING NEW, PASS -BY, AND DIVERTED TRIPS. Wendy's Tukwila The TRANSPO Group, Inc. Figure 2 Total Project Trip Assignment Weekday PM Peak Hour Brian Shelton November 6, 1997 Page 6 The Transpo Group level of service results are shown in Table 3. The level of service calculations are provided in Attachment 3. Table 3. Site Access Level of Service Location/Movement LOS1 Delay2 North Driveway/W Valley Highway WB Left -Tum F >60.0 WB Right -Tum B 8.3 SB Left -Tum D 25.6 South Driveway/W Valley Highway WB Left -Tum F >60.0 WB Right -Tum B 8.2 SB Left -Tum D 25.1 1 Level of Service 2 Average Total Delay (sec/veh) Based on existing traffic volumes on West Valley Highway and project traffic volumes, left -turns from the site access intersections are expected to operate at LOS F. Using methodology in the Highway Capacity Manual, private driveways typically operate at LOS F when located on a roadway with high through volumes. The inbound left -tum movement at both driveways is expected to operate at LOS D. To further evaluate the operations of the site driveways, traffic queues on the driveway approaches were checked. The queuing analysis suggest driveway queues of less than 3 vehicles at each location during the weekday PM peak hour. Vehicle queues of 3 or less at the driveways suggest that queues will not adversely affect internal site circulation. Furthermore, the only form of mitigation for the LOS F condition is to restrict left -turn movements or install a traffic signal at the driveway. However, since a center, two-way, left -turn lane is provided on West Valley Highway, this provides a refuge lane for two-stage left -turn movements from the driveways, which is not explicitly accounted for in the LOS analysis. Unless a corridor improvement is made to divide West Valley Highway, no left -tum restrictions should be considered at the site access driveways. Conclusions The proposed Wendy's restaurant will not generate any new trips to the roadway system. This has been shown through an evaluation of the cumulative impacts of Wendy's and the existing BP station, in comparison with the former Andy's restaurant on-site. Site access intersections are expected to experience delay, however on an acceptable level. Thus, no new impacts as a result of the shared Wendy's/BP facility are anticipated. TL/lmm 97197316\WP\97316TG Transportation and Traffic Engineering PLANNING • DESIGN MEMORANDUM TO: FROM: SUBJECT: Kristen Langley City of Kent The Triiiiij p_ Group DATE: August 21, 1997 Bruce Haldors/Tasha Leshefka TG: 97274.00 The TRANSPO Group, Inc. WENDY'S/TEXACO—TRIP GENERATION ANALYSIS The purpose of this analysis is to identify the project trip generation characteristics for the proposed Wendy's and Texaco combined facility in the City of Kent. The trip generation characteristics were derived from data collected at a similar existing McDonalds/Chevron facilities in Tacoma and Renton. Data was collected at the Tacoma site the week of July 14th. 1997. including site traffic volumes, customer travel patterns, and site characteristics. Data for the Renton McDonalds/Chevron was provided in a Traffic Impart Analysis prepared for a proposed McDonalds/Chevron in Kent, April 22, 1997. The following sections will summarize the project description, the methodology, the data results. and the trip generation characteristics. Project Description The proposed Wendy's/Texaco facility is located on the southwest corner of 64th Avenue S and S 212th Street in Kent, Washington. The project includes a 2,559 sf Wendy's Restaurant with a drive-thru window and a 1.569 sf Texaco "Star Mart" convenience store and gas station. Access to the site is provided from both S 21216 Street and 64th Avenue S. S 212th Street is a four -lane roadway that provides access to SR 161 just east of the project site. . The Tacoma study site includes a 3,400 sf facility. shared between a McDonalds Restaurant and a Chevron convenience store and gas station. The site is located on the east side of Portland Avenue near 112th Street E. in Tacoma, Washington. Portland Avenue is three -lane roadway that provides access to SR 512 just north of the study site. The McDonalds Restaurant has a drive-through window and Chevron has four multi -product vehicle fueling pumps. Access to the site is provided from two driveways on Portland Avenue and through shared driveways with the adjacent retail center. The shared facility has been open and in operation for approximately two months. The Renton McDonalds/Chevron is located at the SW corner of NE 416 Street and Monroe Avenue NE. This site contains approximately 4.500 sf of building area that is shared between McDonalds and Chevron. The Chevron has 12 multi -product vehicle fueling pumps and the McDonalds restaurant has a drive-through window similar to the proposed Wendy's/Texaco. Ms. Kristen Langley August 21, 1997 Page 2 The Trani po Group The study site is Located on an arterial commuter route and at the.intersection of a minor road. The project traffic analysis was provided by City of Kent staff for comparison and use in this traffic analysis. Methodology Traffic data collected for the Renton McDonalds/Chevron study site was obtained from the Traffic Impact Analysis, Gibson Traffic Consultants. April 22. 1997. The PM peak hour and daily site traffic volumes and site square footage were used to determine the associated trip generation rates. Data relating to trip types was also collected by Gibson and used in this analysis. Traffic data was collected at the Tacoma McDonalds/Chevron to determine the overall daily and PM peak hour traffic volumes. In conjunction with the site square footage. the data was used to determine a daily and PM peak hour trip generation rate. The traffic data represents the total traffic generated to the study site, which was divided into three types of trips: Net newtrips. pass -by trips. and diverted trips. Net new trips represent trips new to the study area and site driveways as a direct result of the study site. Pass -by trips represent trips that are not new to the study area roadways, and use the facility as they are passing by the site. Diverted trips represent trips that are already on the study area roadways and change their route to use the facility, as part of a series of stops. These trips are usually made by drivers who have several errands in the vicinity of the site. Customer surveys were conducted to identify the travel patterns of McDonalds/Chevron patrons in terms of new, pass -by, and diverted trips. Traffic Data Traffic data was collected for a three-day. mid -week period in the form of 24-hour mechanical counts at each of the Tacoma McDonalds/Chevron site access driveways. As described previously. the site access driveways are shared with the adjacent retail center. Field observations were used to adjust the counts and separate McDonalds/Chevron traffic from traffic associated with the adjacent retail center. The adjusted volumes resulted in a three day average of 2.304 total daily trips to the McDonalds/Chevron site, with 179 occurring during the PM peak hour of 5 pm to 6 pm. PM peak hour traffic data was collected at the Renton McDonalds/Chevron for a three-day period. An average of 225 PM peak hour trips were counted at the site driveways. No daily traffic volume data was included in the analysis. Customer Survey The methodology for the customer surveys were taken from guidelines and recommendations set forth in the ITE Trip Generation Manual. The survey at the Tacoma McDonalds/Chevron was Ms. Kristen Langley August 21, 1997 Page 3 The Triqi Group conducted on Thursday. July 17th. 1997 between the hours of 4 and 6 pm. Customers were asked the following questions: 1. Where did you just arrive from? (Home, School. Work, or Shopping/Errands) 2. Are you returning to this same destination? (Yes or No) 3. Was it necessary to change your normal driving route to stop at McDonalds/Chevron? (Yes or No) 4. Did you come here to go to: McDonalds, Chevron. or both? The customer survey conducted at the Renton McDonalds/Chevron was also based on the ITE Trip Generation Manual, and was conducted for a two day period during the critical PM peak hour. The purpose of the survey questions was to determine the trip type. based on the customers' origin and next destination. The combination of Questions 1 and 2 identified new trips. Customers arriving from home, school, or work and returning to the sante location indicate a new trip. Alternative. customers arriving from home. school, work. or shopping/errands and not returning to the same location indicated a pass -by or diverted trip. question 3 segments pass -by from diverted trips by indicating if the trip was on the way to another destination, or out of their normal driving route. Question 4 was asked to get a general indication of the split between McDonalds and Chevron users, and was not a factor used to determine trip type. A total of 71 customers were surveyed at the Tacoma McDonalds/Chevron and 128 customers at the Renton McDonalds/Chevron. The results of the customer survey are summarized in Table 1. As shown, approximately 74 percent of the responses indicated a pass -by trip, 7 percent indicated a diverted trip, and 19 percent indicated a new trip. The responses to Question 4 at the Tacoma McDonalds/Chevron indicated that approximately 31 percent of the customers arrived to go to McDonalds only, 52 percent arrived to go to Chevron only, and 17 percent arrived to use both facilities. It should be noted that the survey did not include customers using the McDonalds drive-through window or Chevron's pay -at -the -pump payment method. Table 1. Trip Survey Results Trip Type Study Site Pass -By Diverted New Total Renton 104 7 17 128 Tacoma 44 7 20 71 Total 148 14 37 199 Percent 74% 7% 19% 100% Ms. Kristen Langley August 21, 1997 Page 4 Trip Generation The Triiispij Group Based on the weekday daily and PM peak hour average traffic volumes at the McDonalds/ Chevron sites, the corresponding trip generation rates were calculated. Table 2 summarizes the resulting trip generation rates for each site. Through discussions with City of Kent officials. trip generation rates were developed for the site as a whole. rather than separating trip generation characteristics for McDonalds and Chevron. Table 2. Summary of Trip Generation Study Tacoma McDonalds/Chevron Renton McDonalds/Chevron Trip Generation Study' Trip Generation Study2 Land Use Trips Rate Trips Rate Trips Rate Trips Rate Shared Gas Station and Fast Food Restaurant 2,304 677.6 179 52.6 PUD PUD 225 50.0 1 Based on 3,400 s/ shared facility. 2 Based on 4,500 sf shared facility. N1131:= Not determined. Daily PM Peak Hour Daily PM Peak Hour As shown, the trip generation studies produce an average PM peak hour trip generation rate of 51.3 PM peak hour trips/ 1,000 sf. The data collected at the study sites is comparable to data presented in the ITE manual, which is based on fast food restaurants such as McDonalds. However, McDonalds restaurants typically have higher annual sales than Wendy's restaurants. Wendy's 1996 Annual Report estimates the average sales per Wendy's restaurant, was $998,000 in 1996. In the Nation's Restaurant News article on the top 100 restaurant chains ranked by sales per unit, McDonalds was 34th with an average of $1,439,000 sales per restaurant and Wendy's was 51" with an average of $998.000 sales per restaurant. Based on these annual reports, McDonald's restaurant sales exceed Wendy's restaurants by 44 percent on a per unit basis. Independently, traffic studies conducted at local Wendy's restaurants show a trip rate up to 45 percent lower than those presented in ITE. A 22 percent reduction was applied to the trip generation rates from the study site to account . for the difference in sales trends between a McDonalds restaurant and a Wendy's restaurant. Because the study trip generation rates represent a combination of McDonald's and Chevron customers, the 44 percent difference in annual sales was applied only to the McDonald's portion of the project The McDonald's restaurant represents approximately 50 percent of the study site; thus, approximately half of the 44 percent sales difference, or a 22 percent, was identified as the trip generation reduction. The resulting project trip generation rates for the proposed Wendy's/Texaco, including the 22 percent reduction, equates to 528.5 daily trips per 1,000 sf and 40.0 PM peak hour trips per 1,000 sf. The daily and PM peak hour trip generation in terms of new, pass -by, and diverted trips is shown in Table 3. Ms. Kristen Langley August 21, 1997 Page 5 Table 3. Project Trip Generation - Wendy's/Texaco (4,128 sf) The !aijspo Group PM Peak Hour Trip Type Percent Daily In Out total Total Trips 100% 2,182 82 83 165 Pass -By Trips 74% 1,615 61 61 122 Diverted Trips 7% 153 6 6 12 Net New Trips 19% 414 15 16 31 As shown in Table 3, the proposed Wendy's/Texaco is anticipated to generate a total of 2.182 daily trips with 165 trips occurring during the PM peak hour. Of these trips, approximately 26 percent would be new and/or diverted trips. which equates to 567 daily trips and 43 PM peak hour trips. Mitigation The City of Kent has requested the developer participate in the S 224th/228th Street corridor project to mitigate potential project traffic impacts. The proposed project is located in a rezone area. formally zoned as M-1 and currently zoned as M1 -C. Participation to the corridor project includes $980 per PM peak trip allocated under the former M-1 zoning. and $1960 per PM peak trip for those above the number allocated under the M-1 zoning and included in the MI- C zoning. These corridor participation rates are applied to the net new and diverted trips generated by the project to calculate the overall developer participation. Based on the trip generation rates and trip type percentages identified in this study, the proposed Wendy's/Texaco must mitigate 43 PM peak hour trips. Of the 43 PM peak hour trips, seven (7) trips are applicable towards the M-1 zoning rate and the remaining 36 trips are required to pay the current M1 -C zoning rate. The equivalent developer contribution is $77.420 (in 1986 dollars) towards the S 224th/228th Street corridor project. The City has indicated that the current inflation factor is 1.45, which would equate the 1986 estimate to $112,259 in 1997 dollars. CITY OF TUKWILA • DEPARTMENT OF COMMUNITY DEVELOPMENT Telephone: (206) 431-3670 6300 Southcenter Boulevard, Tukwila, WA 98188 ADDRESS LABEL REQUIREMENTS The City of Tukwila requires that neighboring residents, businesses and property owners be notified of certain types of pending applications in order to encourage citizen participation in the land use process. Applicants are therefore required to submit the following materials: • Mailing labels listing the owners of record for all property within 500 feet of the boundaries (not the center) of the applicant's site (2 sets or 3 sets if SEPA review is.required). • Mailing labels listing the residents or businesses of any property within 500 feet of the property if they are different from the land owners (2 sets or 3 sets if SEPA review is required). • One copy of an assessor's map(s) showing the boundaries of the subject property and the 500 foot radius. 122ND ST ~y �. • -'•. 7' -I23NDST. Property owner names and addresses can be obtained from the King County Department of Assessment located on the 7th floor of the King County Administration Building, Room 700, 500 Fourth Avenue, Seattle. To compile the information required: • Obtain the assessor's map(s) which contain(s) your property and all neighboring properties within 500 feet (See example diagram). You may use the maps on file in the Assessor's Office or purchase a set from the King County Department of Public Works Map Counter on the 9th floor of the Administration Building. Purchased maps must be ordered several hours in advance of the time you would like to pick them up. • After securing the assessor's maps, obtain a "Real Estate Inquiry Batch Request Sheet" from the Department of Assessment. On this form provide the tax account number for each affected property as shown on the assessor's map(s) and submit the completed form to the Department of Assessment with the appropriate fee. Applicants can request that the information be printed in mailing label form or on standard paper. To obtain occupants/resident/business names and addresses, consult the Kroll maps located in the Tukwila Department of Community Development and then visit the site to determine resident names and unit numbers. The information on the mailing labels may refer to "Resident" or "Tenant", with the proper mailing address, if the specific name is unknown. • • ENVIRONMENTAL CHECKLIST Purpose of Checklist: The State Environmental Policy Act (SEPA), chapter 43.21C RCW, requires all governmental agencies to consider the environmental impacts of a proposal before making decisions. An environmental impact statement (EIS) must be prepared for all proposals with probable significant adverse impacts on the quality of the environment. The purpose of this checklist is to provide information to help you and the agency identify impacts from your proposal (and to reduce or avoid impacts from the proposal, if it can be done) and to help the agency decide whether an EIS is required. Instruction for Applicants: This environmental checklist .asks you to describe some basic information about your proposal. The City uses this checklist to determine whether the environmental impacts of your proposal are significant, requiring preparation of an EIS. Answer the questions briefly, with the most precise information known, or give the best description you can. You must answer each question accurately and carefully, to the best of your knowledge. In most cases, you should be able to answer the questions from your own observations or project plans without the need to hire experts. If you really do not know the answer, or if a question does not apply to your proposal, write "do not know" or "does not apply". Complete answers to the questions now may avoid unnecessary delays later. Some. questions ask about governmental regulations, such as zoning, shoreline, and landmark designations. Answer these questions if you can. If you have problems, the City staff can assist you. The checklist questions apply to all parts of your proposal, even if you plan to do them over a period of time or on different parcels of land. Attached any additional information that will help describe your proposal or its environmental effects. The City may ask you to explain your answers or provide additional information reasonably related to determining if there may be significant adverse impact. Use of checklist for nonproject proposals: Nonproject proposals refer to actions which are different or broader than a single site specific development project, such as plans, policies and programs. Complete this checklist for nonproject proposals, even though questions may be answered "does not apply". In addition, complete the supplemental sheet for nonproject actions (part D). For nonproject actions, the references in the checklist to the words "project", "applicant", and "property or site" should read as "proposal", "proposer", and "affected geographic area", respectively. • A. BACKGROUND ENVIRONMENTAL CHECKLIST Cont.No. Epic File No. Fee $ 325 Receipt No. 1. Name of proposed project, if applicable: WENDY'S RESTAURANT 2. Name of applicant: Wendy's Tnternatinnal 3. Address and phone number of applicant and contact person: Jim Anderson, Ruhl-Parr & Associates, 3625 -132nd Ave. SE, Suite 100, Bellevue, WA 98006 Phone 425-644-4000 Fax: 425-643-4115 4. Date checklist prepared: 11/3/97 5. Agency requesting Checklist: City of Tukwila 6. Proposed timing or schedule (including phasing, if applicable): Begin construction 5/1/98. end construction 9/1/98 7. Do you have any plans for future additions, expansion, or further activity related to or connected with this proposal? If yes, explain. No 8. List any environmental information you know about that has been prepared, or will be prepared, directly related to this proposal. BP station to_Ibe north and adjacent to our property has already filed for permit and had an environmental review checklist attached, presumably. 9. Do you know whether applications are pending for governmental approvals of other proposals directly affecting the property covered by your proposal? If yes, explain. RP statinn adjarent to the nnrth of roar property. Building permit aalrPady applied fnr -2- • • 10. List any government approvals or permits that will be needed for your proposal. Tukwila Building Permit, Seattle/King County _Health Permit- Tukwila Parking Lot Permit, Sign Permit. Mechanical Permit. and State Electrical - Permit. 11. Give brief, complete description of your proposal, including the proposed uses and the size of the project and site. There are several questions later in this checklist that ask you to describe certain aspects of your proposal. You do not need to repeat those answers on this page. Section E requires a complete description of the objectives and alternatives of your proposal and should not be summarized here. 12. Location of the proposal. Give sufficient information for a person to understand the precise location of your proposed project, including a street address, if any, and section, township, and range, if known. If a proposal would occur over a range of area, provide the range or boundaries of the site(s). Provide a legal description, site plan, vicinity map, and topographic map, if reasonably available. While you should submit any plans required by the agency, you are not required to duplicate maps or detailed plans submitted with any permit applica- tions related to this checklist. 16200 West Valley Highway in Tukwila. Washington. Site is to the__nnrth and adjacent to an existing Taco Bell and to the south and nrljaci-nt to a new BP gas station and carwash. The sit1s the south Portion of -the former Andy's Diner. 13. Does the proposal lie within an area designated on the City's Comprehensive Land Use Policy Plan Map as environmentally sensitive? -3- TO BE COMPLETED BY APPLICAA B. ENVIRONMENTAL ELEMENTS • 1. Earth a. General description of the site (circle one): Flat, rolling, hilly, steep slopes, mountainous, other b. What is the steepest slope on the site (approximate percent slope)? 5% c. What general types of soils are found on the site (for example, clay, sand, gravel, peat, muck)? If you know the classification of agricultural soils, specify them and note any prime farmland. Silty sand fill ovelaying natural silt and sand allyi um. d. Are there surface indications or history of unstable soils in the immediate vicinity? If so, describe. No e. Describe the purpose, type, and approximate quanti- ties of any filling or grading proposed. Indicate source of fill. There may be some modest amounts of fill, but only as necessary to bring the areas around the building into conformance with ADA regarding accessibility and site slopes to join the parking area to the building on piles. f. Could erosion occur as a result of clearing, construction, or use? If so, generally describe. No g. About what percent of the site will be covered with impervious surfaces after project construction (for example, asphalt or buildings)? -4- Evaluation for Agency Use Only • • h. Proposed measures to reduce or control erosion, or other impacts to the earth; if any: The civil drawings indicate erosion control measures 2. Air a. What types of emissions to the air would result from the proposal (i.e., dust, automobile odors, industrial wood smoke) during construction and when the project is completed? If any, generally describe and give approximate quantities if known. Construction: typical construction equipment diesel engines. etc. Typical operation: Customer automobile exhaustt and air from the grill hoed b. Are there any off-site sources of emissions or odor that may affect your proposal? If so, generally describe. No c. Proposed measures to reduce or control emissions or other impacts to air, if any: Two drive-through windows which are designed to minimize wait time while the engine is idling. 3. Water a. Surface: 1) Is there any surface water body on or in the immediate vicinity of the site (including year- roundand seasonal streams, saltwater, lakes, ponds, wetlands)? If yes, describe type and provide names. If appropriate, state what stream or river it flows into. Nn -5- Evaluation for Agency Use Only • • 2) Will the project require any work over, in, or adjacent to (within 200 feet) the described waters? If yes, please describe and attach available plans. No 3) Estimate the amount of fill and dredge material that would be placed in or removed from surface water or wetlands and indicate the area of the site that would be affected. Indicate the source of fill material. None 4) Will the proposal require surface water withdrawals or diversions? Give general description, purpose, and approximate quan- tities, if known. No 5) Does the proposal lie within a 100 -year floodplain? If so, note location on the site plan. No 6) Does the proposal involve any discharges of waste materials to surface waters? If so, describe the type of waste and anticipated volume of discharge. No -6- Evaluation for Agency Use Only • • b. Ground: 1) Will ground water be withdrawn, or will water be discharged to ground water? Give general description, purpose, and approximate quan- tities, if known. No 2) Describe waste materials that will be discharged into the ground from septic tanks or other sour- ces, if any (for example: Domestic sewage; industrial, containing the following chemicals...; agricultural; etc.) Describe the general size of the system, the number of such systems, the number of houses to be served (if applicable), or the number of animals or humans "the system(s) are expected to serve. None All wastes will he delivered to the Tukwila Sanitary Sewage System with a grease interruptor to collect cooking greases The stnrm water runoff will be diverted to rhe Tukwila storm sewer system and will include a hinswale c. Water Runoff (including storm water): Evaluation for Agency Use Only 1) Describe the source of runoff (including storm water) and method of collection and disposal, if any (include quantities, if known). Where will this water flow? Will this water flow into other waters? If so, describe. The storm dater will be from rains falling on on-site impervious surfaces. It will be drained through a bioswale and a controlled outlet. See Civil drawings. -7- • • 2) Could waste materials enter ground or surface waters? If so, generally describe. No d. Proposed measures to reduce or control surface, ground, and runoff water impacts, if any: CnntrollPd rP1P,aSe SeP Civil drawings 4. Plants a. Check or circle types of vegetation found on the site: deciduous tree: alder, maple, aspen, other y evergreen tree: fir, cedar, pine, other x shrubs x grass pasture crop or grain wet soil plants: cattail, buttercup, bullrush, skunk cabbage, other water plants: water lily, eelgrass, milfoil, other other types of vegetation b. What kind and amount of vegetation will be removed or altered? Shrubs in existing landscape areas in the existing parking lot will be replaced by other shrubs in the new landscape areas within the reworked parking area. c. List threatened or endangered species known to be on or near the site. None Evaluation for Agency Use Only • • d. Proposed landscaping, use of native plants, or other measures to preserve or enhance vegetation on the site, if any See land 5. Animals a. Circle any birds and animals which havebeen observed on or near the site or are known to be on or near the site: birds: hawk, heron, eagle, songbirds, other: Starling crow rohinc mammals: deer, bear, elk, beaver, other: None fish: bass, salmon, trout, herring, shellfish, other: None b. List any threatened or endangered species known to be on or near the site. None c. Is the site part of a migration route? If so, explain. None d. Proposed measures to preserve or enhance wildlife, if any: New landscaping -9- Evaluation for Agency Use Only • 6.- Energy and Natural Resources a. What kinds of energy (electric, natural gas, oil, wood stove, color) will be used to meet the completed project's energy needs? Describe whether it will be used for heating, manufacturing, etc. Gas heat and cooking. Electric lighting,. b. Would your project affect the potential use of solar energy by adjacent properties? If so, generally describe. No c. What kinds of energy conservation' features are included in the plans of this proposal? List other proposed measures to reduce or control energy impacts, if any: The project will meet the Washington State Energy Code. 7. Environmental Health a. Are there any environmental health hazards, including exposure to toxic chemicals, risk of fire and explosion, spill, or hazardous waste, that could occur as a result of this proposal? If so, describe. None 1) Describe special emergency services that might be required. Police, Fire, Medic 1 2) Proposed measures to reduce or control environ- mental health hazards, if any: N/A -10- Evaluation for Agency Use Only • • b. Noise 1) What types of noise exist in the area which may affect your project (for example: traffic, equipment, operation, other)? The West Valley Highway is a high-volume traffic corridor. but it should not affect our project. The railroad tracks to the east are frequently used, but should not affect Wendy's. 2) What types and levels of noise would be created by or associated with the project on a short- term or a long-term basis (for example: traf- fic, construction, operation, other)? Indicate what hours noise would come from the site. Only typical construction noises would be generated during the months of construction. There will be an auger machine to drill for piling for the first 2-4 weeds of construction. 3) Proposed measures to reduce or control noise impacts, if any: Nnne 8. Land and Shoreline Use a. What is the current use of the site and adjacent properties? The site used to hay. an Andy's Diner. but the buildings have heen removed within the last year. b. Has the site been used for agriculture? If so, describe. Unknown. Not for at least 20 years. if ever. c. Describe any structures on the site. None. The Andy's Diner buildings have been removed. -11- Evaluation for Agency Use Only • d. Will any structures be demolished? If so, what? No e. What is the current zoning classification of the site? Tukwila Urban Center f. What is the current comprehensive plan designation of the site? Tukwila Urban Center g. If applicable, what is the current shoreline master program designation of the site? N/A h. Has any part of the site been classified as an "environmentally sensitive" area? If so, specify. No i. Approximately how many people would reside or work in the completed project? j maximum shift would he ahnut 17 -I. • -- • .'•. Y. -re will be no residents. - j. Approximately -how many people would the completed project displace? None k. Proposed measures to avoid or reduce displacement impacts, if any: N/A 1. Proposed measures to ensure the proposal is com- patible with existing and projected land uses and plans, if any: It conforms to Tul�il_a Urban Center -12- Evaluation for Agency Use Only • • 9. Housing a. Approximately how many units would be provided; if any? Indicate whether high, middle, or low-income housing? N/A b. Approximately how many units, if any, would be eli- minated? Indicate whether high, middle, or low- income housing. N/A c. Proposed measures to reduce or control housing impacts, if any: N/A 10. Aesthetics a. What is the tallest height of any proposed structure(s), not including antennas; what is the principal exterior building material(s) proposed? 18'0" ,-'.1 - • • •- • -•-- ' L.__ formedmetal fascia b. What views in the immediate vicinity would be altered or obstructed? None c. Proposed measures to reduce or control aesthetic impacts, if any: Use of earth tone brick tQ. minimize° impact. -13- Evaluation for Agency Use Only • 11. Light and Glare a. What type of light or glare will the proposal produce? What time of day would it mainly occur? The parking area will hp lit at night b. Could light or glare from the finished project be a safety hazard or interfere with views? No c. What existing off-site sources of light or glare may affect your proposal? None d. Proposed measures to reduce or control light and glare impacts, if any: Maintain parking lot lighting oriented to illuminate parking and pedestrian walkway, not the neighboring properties. 12. Recreation a. What designed and informal recreational oppor- tunities are in the immediate vicinity? Tukwila Centennial Park within a mile and a pedestrian trail paralleling the railroad tracks to the east. b. Would the proposed project displace any existing recreational uses? If so, describe. Na c. Proposed measures to reduce or control impacts on recreation, including recreation opportunities to be provided by the project or applicant, if any: None -14- Evaluation for Agency Use Only • 13. Historic and Cultural Preservation a. Are there any places or objects listed on, or pro- posed for, national, state, or local preservation registers known to be on or next to the site? If so, generally describe. Nn b. Generally describe any landmarks or evidence of historic, archaeological, scientific, or cultural importance known to be on or next to the site. None c. Proposed measures to reduce or control impacts, if any: N/A 14. Transportation a. Identify public streets and highways serving the site, and describe proposed accss to the existing street system. Show on site plans, if any. The site is adjacent to West Valley Highway. A new access will be developed and shared with the new BP station to the north. b. Is the site currently served by public transit? If not, what is the approximate distance to the nearest transit stop? Ye c. How many parking spaces would the completed project have? How many would the project eliminate? 42 new, The Andy's Diner had narking which has been abandoned. -15- Evaluation for Agency Use Only • • d. Will the proposal require. any new roads or streets, or improvements to existing roads or streets, not including driveways? If so, generally describe (indicate whether public or private). No e. Will the project use (or occur in the immediate vicinity of) water, rail, or air transportation? If so, generally describe. No f. How many vehicular trips per day would be generated by the completed project? If known, indicate when peak volumes would occur. Approximately 300 trips would be generated, but it is assumed a high percentage of these trips would be from people already passing by and there would be few trips initiated because of the new Wendy's. g. Proposed measures to reduce or control transpor- tation impacts, if any: None 15. Public Services a. Would the project result in an increased need for public services (for example: fire protection, police protection, health care, schools, other)? If so, generally describe. No b. Proposed measures to reduce or control direct impacts on public services, if any. None -16- Evaluation for Agency Use Only • • 16. Utilities a. Circle utilities currently available at the site: electricity, natural gas, water, refuse service, telephone, sanitary sewer, septic system, other. b. Describe the utilities that are proposed for the project, the utility providing the service, and the general construction activities on the site or in the immediate vicinity which might be needed. Gas & 6lectricity - Puget Sound Energy Sewer & Water - Tukwila Utilities Phone - US West Refuse - Waste Management C. Signature The above answers are true and complete to the best of my knowledge. I understand that the lead agency is relying on them to make its decision. Signature: Date Submitted: PLEASE CONTINUE TO THE NEXT PAGE. -17- Evaluation for Agency Use Only • TO BE COMPLETED BY APPLICANT Evaluation for Agency Use Only D. SUPPLEMENTAL SHEET FOR NONPROJECT ACTIONS (do not use this sheet for project actions) Because these questions are very general, it may be helpful to read them in conjunction with the list of the elements of the environment. When answering these questions, be aware of the extent the proposal, or the types of activities likely to result from the proposal, would affect the item at a greater intensity or at a faster rate than if the proposal were not imple- mented. Respond briefly and in general terms. 1. How would the proposal be likely to increase discharge to water; emissions to air; production, storage, or release of toxic or hazardous substances; or production of noise? Proposed measures to avoid or reduce such increases are: 2. How would the proposal be likely to affect plants, ani- mals, fish, or marine life? ' Proposed measures to protect or conserve plants, ani- mals, fish, or marine life are: -18- • • 3. How would -the proposal be likely to deplete energy or natural resources? Proposed measures to protect or conserve energy and natural resourses are: 4. How would the proposal be likely to use or affect environmentally sensitive areas or areas designated (or eligible or under study) for governmental protection; such as parks, wilderness, wild and scenic rivers, threatened or endangered species habitat, historic or cultural sites, wetlands, floodplains, or prime farmlands? Proposed measures to protect such resources or to avoid or reduce impacts are: 5. How would the proposal be likely to affect land and shoreline use, inclduing whether it would allow or encourage land or shoreline uses incompatible with existing plans? -19- Evaluation for Agency Use Only • • Proposed measures to avoid or reduce shoreline and land use impacts area: How does the proposal conform to the Tukwila Shoreline Master Plan? 6. How would the proposal be likely to increase demands on transportation or public services and utilities? Proposed measures to reduce or respond to such demand(s) are: 7. Identify, if possible, whether the proposal may conflict with local, state, or federal laws or requirements for the protection of the environment. -20- Evaluation for Agency Use Only • • 8. Does the proposal conflict with policies of the Tukwila Comprehensive Land Use Policy Plan? If:so, what poli- cies of the Plan? Proposed measures to avoid or reduce the conflict(s) are: -21- Evaluation for Agency Use Only TO BE COMPLETED BY APPLIC• • E. SUPPLEMENTAL SHEET FOR ALL PROJECT AND NON PROJECT PROPOSALS The objectives and the alternative means of reaching the objectives for a proposal will be helpful in reviewing the aforegoing items of the Environmental Checklist. This information provides a general overall perspective of the proposed action in the context of the environmental infor- mation provided and the submitted plans, documents, suppor- tive information, studies, etc. 1. What are the objective(s) of the proposal? 2. What are the alternative means of accomplishing these objectives? 3. Please_compare the alternative means and indicate the preferred course of action: -22- Evaluation for Agency Use Only January 22, 1997 Mr. Roger 011enberg Roger 011enberg/Architect 515 - 116th Avenue NE, Suite 202 Bellevue, WA 98004 DAVID EVANS AND ASSOCIATES,. gga INC.... 415 -118th Avenue S.F.- Bellevue. Washington 98005 Tel: 206.455.3571 Fax: 206.455.3061 SUBJECT: SOUTHCENTER BP SERVICE STATION TRAFFIC STUDY Dear Mr. 011enberg: This letter report summarizes the trip generation estimate, trip distribution, and traffic assignment for the proposed BP service station located at 16200 West Valley Highway in the City of Tukwila. It also compares the trip generation resulting from the proposed BP service station with that of the previous land use - Andy's Restaurant. The City has requested that this analysis be prepared to address traffic -related impacts associated with the proposed gas station. Project trip generation is also compared with the impacts of restaurant trip generation. The specific scope of this study was determined in coordination with the City of Tukwila Public Works Department. Project Description The new service station would include 12 vehicle fueling positions, a 2,288 square foot convenience store with a drive -up window, and a conveyor system car wash. Two 35 -foot -wide driveways would provide access to the station from West Valley Highway (SR 181). At some point in the future, there is a possibility that the southern driveway would be shared with the site to the south. The project would be completed by 1997. Trip Generation - Proposed BP Service Station Daily, AM, and PM peak hour trip generation estimates for the project were based on the trip rates for Gasoline/Service Station with Convenience Market and Car Wash (Land Use 846), as described in Trip Generation: Update to the 5th Edition (Institute of Transportation Engineers, February 1995). Total daily, AM peak hour, and PM peak hour trip generation estimates are summarized in Table 1. Table 1: .Service Station Trip Generation (Total Trips) Tine Period .In AM Peak Hour 66 vph 65 vph PM Peak Hour 74 vph 75 vph Daily 874 vpd 874 vpd . ....Total . • 131vph 149 vph 1,748 vpd Trip generation estimates for the project should reflect the effects of pass -by trips. Pass -by trips are those trips that are already located on the street that abuts the site, and rather than passing the site as they did before the development was in place, they turn into the site. These trips are not new to the street system. However, the trips are new at the project driveways. It is estimated that 54 percent of the AM peak hour site -generated trips Outstanding Professionals: ::.:Outstandin.. •uali E 11 B r DAVID EVANS AND. ASSOCIATES, Mr. Roger 011enberg January 22, 1997 Page 2 of 4 ggpa INC.. and 58 percent of the PM peak hour site -generated trips would be pass -by trips'. A pass -by rate of 54 percent is a conservative estimate of the daily pass -by trip rate. Net new trips are those trips that are new to the street system, in other words, the difference between the total trips as pass -by trips. Table 2 summarizes the net new daily, AM peak hour, and PM peak hour trip generation estimates. Table 2: Service Station Trip Generation. iine Period '; Total :Trips Minus. Pass.byTrips = Net New Trips AM Peak Hour 131 vph 76 vph 55 vph PM Peak Hour 149 vph 86 vph 63 vph Daily 1,748 vpd 1014 vpd 734 vpd Trip Generation - Previous Land Use (Andy's Restaurant) This property was previously the site of Andy's Restaurant. From the Boundary and Topography Survey of the site, done in 1995, it was determined that the size of the restaurant was approximately 11,200 square feet. Daily, AM and PM peak hour trip generation estimates have been made for the restaurant, based on the trip rates for High Turnover (Sit -Down) Restaurants (Land Use 832), as described in Trip Generation: Update to the 5th Edition. The total daily, AM and PM peak hour trip generation estimates for the restaurant are shown in Table 3. The number of pass -by trips generated by restaurants is considered to be negligible. Table 3, therefore, represents the total new traffic which would have used SR 181 to access the restaurant. Table 3: Restaurant Trip Generation Time Period ';. :In::: ;:;Out... ?:To AM Peak Hour 85 vph 81 vph 166 vph PM Peak Hour 81 vph 64 vph 145 vph Daily - 996 vpd 996 vpd 1,992 vpd Table 4 provides a comparison between the trips generated by the previous and proposed uses of the site. As shown in Table 4, the restaurant generated more traffic than is expected to be generated by the proposed service station. The amount of traffic which is expected to be added to SR 181 due to the service station should therefore not be any greater than the amount of traffic which used SR 181 to access the restaurant. t Institute of Transportation Engineers, Trip Generation, An Informational Report 56 Ed (Washington, D.C.): 1365 Outstanding Professionals ... Outstanding Quality 1A EMBER Mr. Roger 011enberg January 22, 1997 Page 3 of 4 Table 4: Trip Generation Comparison (Net New Trips) INC. Timc.Pcriod.: :: <.. 'Previous:Use :: 'Proposed;Use.... : %:Change. (Andy's. Restaurant) (BP. Service Station) AM Peak Hour 166 vph 55 vph PM Peak Hour 145 vph 63 vph Daily 1,992 vpd 734 vpd -67% - 57 % - 63 % Trip Distribution and Traffic Assignment The distribution of project -generated trips was based on traffic volumes on the adjacent roadway, SR 181. These traffic volumes are shown in Figure 1. In the AM peak hour, approximately 42 percent of the traffic is northbound, while approximately 51 percent of the traffic is northbound during the PM peak hour. It is assumed that the site generated trips will follow this same distribution: i.e., 42 percent of the generated traffic will come from the south in the AM peak hour, and 51 percent will come from the south in the PM peak hour. Future improvements to SR 181 may result in restrictions to permitted turning movements at the site driveways. Therefore, both divided (restricted access) and undivided (full access) scenarios were examined. Figure 2 shows the expected distribution of traffic, assuming the highway remains undivided. Figure 3 shows the distribution in the event that the highway becomes divided, which would result in right in/right out access only. It is assumed for both distributions, that 80% of the traffic will use the northern driveway, which allows sole access to the service station. The remaining 20% is expected to use the southern driveway, which provides joint access to the northern (potential BP Service Station) and southern (potential restaurant) portions of this site. Figures 2 and 3 show the expected new trips, pass -by trips, and the total project generated trips. It is assumed that both the new and pass -by trips will have similar travel patterns, and therefore are distributed and assigned as described above. INC. Mr. Roger 011enberg January 22, 1997 Page 4 of 4 Thank you for this opportunity to provide you with transportation engineering services. We look forward to working with you again in the future. Please feel free to share this letter with agencies from whom you are seeking permits. We are available to further discuss project trip generation and other issues if you or the permitting agencies have any questions. Sincerely, DAVID EVANS AND ASSOCIATES, INC. Kerensa L. Swanson Transportation n: eer oris Transportation Engineer FJV:KLSW:dml Enclosure p:\o\oevt0005\t-t\cloc\ltr_rpt.cloc OEVT0005 I -22-R7 (EXPIRES 1 / 21 / 7/ 0 J 0 NI z 0 1 0 N 0 0 0 W 0 0 z BigCo INC. SOUTHCENTER BP 1996 EXISTING TRAFFIC VOLUMES FIGURE 1 0 J . O T1 rl _d 0 1 U 0 I) 0 0 0 w 0 0 INC. SITE Tot en al v 10 v N M N1 a J l� 9 (13) 13 (18) a . North MOT TO SCALE SR 181 West Valley Highway - eM �p MJ 2(3) 3(3) a a AM PEAK HOUR LEGEND New Trips (Pass -By Trips) 1 1 Total Trips SOUTHCENTER BP PROJECT GENERATED DRIVEWAY VOLUMES (No Tum Restrictions) FIGURE 2 0 -J - O •O.OEvT0005'.TT••.Ov,0G INC. LEGEND New Trips (Pass -By Trips) ® Total Trips SOUTHCENTER BP PROJECT GENERATED DRIVEWAY VOLUMES (With Left Tum Restrictions) FIGURE 3 Attachment 2 Wendy's/Texaco Trip Generation Analysis HCS: Unsignalized Intersections Release 2.1d WVHNDYWP.HCO Page 1 ====== ac=== ===========================---= The TRANSPO Group 14335 NE 24th Street Suite 201 Bellevue, WA 98007-3737 Ph: (425) 641-3881 Streets: (N -S) W VALLEY HIGHWAY (E -W) NORTH DRIVEWAY Major Street DirectionNS Length of Time Analyzed15 (min) Analyst TL Date of Analysis 11/5/97 Other Information WITH PROJECT CONDITIONS Two-way Stop -controlled Intersection No. Lanes Stop/Yield Volumes PHF Grade MC's (%) SU/RV's (%) CV's (%) PCE's Northbound Southbound L T R L T R O 2< 0 1 2 0 N 1729 29 29 1657 .95 .95 .95 .95 0 0 1.10 N Eastbound L T R O 0 0 Westbound L T R 1 0 1 29 29 .95 .95 0 1.10 1.10 Adjustment Factors Vehicle Critical Follow-up Maneuver Gap (tg) Time (tf) Left Turn Major Road Right Turn Minor Road Through Traffic Minor Road Left Turn Minor Road 5.50 5.50 6.50 7.00 2.10 2.60 3.30 3.40 o HCS: Unsignalized Intersections Release 2.1d WVHNDYWP.HCO Page 2 Worksheet for TWSC Intersection Step 1: RT from Minor Street WB EB Conflicting Flows: (vph) 926 Potential Capacity: (pcph) 470 Movement Capacity: (pcph) 470 Prob. of Queue -Free State: 0.93 Step 2: LT from Major Street SB NB Conflicting Flows: (vph) 1851 Potential Capacity: (pcph) 174 Movement Capacity: (pcph) 174 Prob. of Queue -Free State: 0.80 Step 4: LT from Minor Street WB EB Conflicting Flows: (vph) Potential Capacity: (pcph) Major LT, Minor TH Impedance Factor: Adjusted Impedance Factor: Capacity Adjustment Factor due to Impeding Movements Movement Capacity: (pcph) 3610 5 0.80 0.80 0.80 4 Intersection Performance Summary Avg. 95% Flow Move Shared Total Queue Approach Rate Cap Cap Delay Length LOS Delay Movement (pcph) (pcph) (pcph)(sec/veh) (veh) (sec/veh) WB L 34 4 * 4.0 F WB R 34 470 8.3 0.1 B SB L 34 174 25.6 0.7 D Intersection Delay = 42.5 sec/veh * The calculated value was greater than 999.9. * 0.4 HCS: Unsignalized Intersections Release 2.1d WVHSDYWP.HCO. Page 1 The TRANSPO Group 14335 NE 24th Street Suite 201 Bellevue, WA 98007-3737 Ph: (425) 641-3881 Streets: (N -S) W VALLEY HIGHWAY Major Street DirectionNS Length of Time Analyzed15 (min) Analyst TL Date of Analysis 11/5/97 Other Information WITH PROJECT CONDITIONS Two-way Stop -controlled Intersection (E -W) SOUTH DRIVEWAY No. Lanes Stop/Yield Volumes PHF Grade MC's (a) SU/RV's (o) CV's (°s) PCE's Northbound L T R O 2 < 0 N 1758 22 .95 .95 0 Southbound L T R 1 2 0 23 1634 .95 .95 0 1.10 N Eastbound L T R O 0 0 Westbound L T R 1 0 1 22 23 .95 .95 0 1.10 1.10 Adjustment Factors Vehicle Critical Follow-up Maneuver Gap (tg) Time (tf) Left Turn Major Road Right Turn Minor Road Through Traffic Minor Road Left Turn Minor Road 5.50 5.50 6.50 7.00 2.10 2.60 3.30 3.40 HCS: Unsignalized Intersections Release 2.1d WVHSDYWP.HCO Page 2 Worksheet for TWSC Intersection Step 1: RT from Minor Street WB EB Conflicting Flows: (vph) 937 Potential Capacity: (pcph) 464 Movement Capacity: (pcph) 464 Prob. of Queue -Free State: 0.94 Step 2: LT from Major Street SB NB Conflicting Flows: (vph) 1874 Potential Capacity: (pcph) 169 Movement Capacity: (pcph) 169 Prob. of Queue -Free State: 0.85 Step 4: LT from Minor Street WB EB Conflicting Flows: (vph) Potential Capacity: (pcph) Major LT, Minor TH Impedance Factor: Adjusted Impedance Factor: Capacity Adjustment Factor due to Impeding Movements Movement Capacity: (pcph) 3606 5 0.85 0.85 0.85 4 Intersection Performance Summary Avg. 95% Flow Move Shared Total Queue Approach Rate Cap Cap Delay Length LOS Delay Movement (pcph) (pcph) (pcph)(sec/veh) (veh) (sec/veh) WB L 25 4 * 2.9 F WB R 26 464 8.2 0.0 B SB L 26 169 25.1 0.5 D Intersection Delay = 25.9 sec/veh * The calculated value was greater than 999.9. * 0.3 • o w r p di. MR ,wart[ nvmntM t i-1 I :(LL ---'1"" 1 77-7,,w,-11.71,7,..,:::"...11..:.... ' . - - - - - ---• : 1. ' . . . . \ \--" di ‘ . " II to ,i' vrillrca.ALS. )J� i� `r.'t yEST JI.LLEY'N16��•Y l5R ID1) RECEIVED CITY OF TUKWILA N 0 V 1 2 1997 PERMIT CENTER 11 F'IELFIMnRY BIDD TR O eQ11R1CTom = AWL FLAN No. • c9-3480 YEcr Ne. 14 �,•NS VICINITY MAP NOT TO SCALE LEGEND ---BE BE WANED ELECTRIC BP BP___ BOWED POMR ---Bf BI--- BURIED TELEPHONE • FL___ FOG UM G•5 MEGAN LIME 5* SD SD___ STORM MAN SANITARY SARK AMER BOLLARD C. CEDAR C.B. CATCH BASH 0. DECIDUOUS. H.N. HIRE HYDRANT ND HONE ILLLMNARE M.N OLE POWER POLE T.S. CENTRIy 00(17C SEM RR VALVE mal ELEVATION NOW: ME LIMITE5 SHORN HEREON, UNLESS SHOWN PIM SURFACE APPURTENANCES. ARE PER PUBIC RI RECORD ONLY. PRIOR TO ANY CONSTRUCTION AND/OR EXCAVATION. THEIR EXACT LOCATION 4NOAD BE DETERMINED BY CALLING ONE -CALL LOG•TE AT 1 -Boo -LLL -SSSS. ZONING — T.U.C. DE PROPERTY AND ADJACENT PROPERTY IS ZONED TUKWILA URBAN CENTER. SEIOACNS FRONT: 1S SIVE: ID REM: 10' HEIGHT RESTRICTIONS: 115' IVO If ELLER nos FAN NO. ,? XMNI N 0127 _W ---t------- P.S.P. & L. CO. RIGHT OF WAY TUKWILA SHORT PLAT NO LOT 1 7UNMLA STATM0 LLC. BOO OESTL•KE A SEATTLE, NA 98109 BENCHMARK SET CH191ED SOUS50 ON SV CORNER CF CMC. BASE. ELEV. 2198 DATUM - OTT a TI NFALA 0122'22 W NrAX. RATE EN NEEL TRATIsewpm NNE WANEAD PON* LEGATE./ or XL.. INNER UMLPROVED AREA PAM. A NT LEGAL DESCRIPTION L07 2 0Fa TUKML• 91107 NAT No. ___ , •5 RE,;13 O 0x0(0 Nlxc HOMO 1(0020 Ixc No __--_-_-' RECIAN9 a KING cMH1r, WASHINGTON. NOTES: 1' n1100210RT:IDortUUSR.1997"0401Co.ORT NO es. D AUGUST e, 2. ME PARCEL 41000 15 NOTA LEGALLY SEGREGATED PARCEL. BUT R•THCR THAT OE A PARCEL MACH PILL RESULT FROM A PROPOSED SNORT PLAT. J. ME LEGAL OE5CNPTIM SPOw IS NOT 711E RECORD LEGAL OESCMPTION, WI RATHER NAT Or A PARCEL PHICH MU RESULT FIRM A A PROPOSED SHORT 0.01, CERTIFICATE I HEREBY CERTIFY TO WEHDYS w1ERNATIMAL NC. AND COMPANY AND TO CHICAGO TITLE INSURANCE CO. THAT THIS SURVEY HAS BEEN [CATERED TROM A 91RTEv ACTUALLY MADE M I' GROUND ORM5I DER MY SUPERON ON AUGUST 13. 1997; 1 IS CORRECT; AND MAT IT COMMIES MM THE REOUNEHEN TS OF KNOT'S INTERNATIONAL. NC. DAM: SEPTEMBER 3, 1997 CERTIFICATE H0. 10003 R[AxP�S �aIMN! 9T�404 ,. art t 1, BENCHMARK 1 RR NINE IM EAST FACE OF PoMER POLE 1 REV. 26.53 1 0,7•4_11-'9=2—';"••-0 ••., 57, 1_ eL 6 • r �V LLEY HIGHWAY (S.R. 181)• } QST � BEAIRN - N OB'S1 TT -1 - GRAPHIC SCALE IN FEET 2D' 0' ID 20' AD' 1" _ 20' ANN•L1 POADM•Y Nm 07 WM M — .PrS AREA = 31,837 SO. FT.t = 0.73 AC.t Porto. OF t•X LOT HO 0105 0-0030-00 601 92r- _� 116571 ▪ NR• .COW TAR WENDY'S INTERNATIONAL, INC. BOUNDARY AND TOPOGRAPHIC SURVEY A 1 16200' NEST VALLEY HIGHWAY. TUK'MLA, MING COUNTY, WASHINGTON TIM HANSON AND ASSOCIATES, INC. 0025 1M AVE s KRCL.AJJq WA WOW noel BT9-727 _ 20_125 23 • I 144 J AUGUST 7R7i_ = 7,77==7727- PLANT SCHEDULE SYMBOL BOTANIC NAME/ COMMON NAME SIZE AND NOTES 0 0 PLANTING PLAN soma A1PP A CRATAEOJE PMAIOICPYR161/ PIAEMOCITOPIPIAAIMORM SLAP/A SOMATA' VON VASE/ A PRIEXVIVUOA MITZIE511/ DOLMAS FIR RNOPOIPLIRON CLIINIMSNAPP6 PHIL / 0...616.51441.6 KITE RACOCOENDRON ILE% CORPLMA ROTLADAY OMAR? COMM MOLLY AZALEA PALA! 10o< 1/11,612 EVIMOREEM AZALEA MEWS'S ARMES WAAPThil KINIACESASK SEASONAL COLOR. ASIVALSCRPERM yr/ SeG17 BIOSPIALE Vf113 PIIN LOC CITY OP TWMtA STAJOAPD 2 CAI..7 6-6 FT. M. 21-24. MT. 2 SAL. 2 OAL I 6AL COM RATE CP A' POT! ALL PLAPITTe EIEDS TO Pl!CCV E A 14604.01 CP 2. BARK CR 1.000C4IIP NW. MIL RILL 0:0 M�** RENOSTORA AND •ISOCtATES um= Amnon= ==== WIT'S TURIALA ...A A.. KA/11110 KAN 6 A 6 A A A A 6 6 ••••••• 0•0•Mi. MAU .11 Ow "LOA? 1•1•,116. L-1 we., I OA • 1 FLOOR 1 1 ROOH FMISH SCHEDULE ease a 1 1 WALLS 1 1 CELE* Tp7 Doo 111 w e W I YeSTEWS MOS IOWA Mt* RCM 01110 IWO/ 11.401 AIWA ele•Aei MBA ONO AIWA • • • • 0 • • • • • • • • O • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • UM • • • eteilde 001 0.011, . • • • • • • • • • • • • • • O'a wranw Erma c• •Mae 1. seez. WOW TO We cum 0e-•• caw maw p..M • a.arsae C) cove maw 1 • • • • • • • • • • • • • • • • • • • • • rep •• 61000. D•e •su • • • • • • • • Daae w� lh• a • • • • DOOR AND HARDWARE SCHEDULE TYPE • • • • • • • • • FROM • • • • • • • • 1 • a a LIFO/E6 a • • • • LATCU-umEe 1 • • • • • • • • • • a • • • • • • • • • • • • • • • • • • RCC. 6 • • • a 0 a • a • 0 �i m cruces run w• w• •acor on 1.00,0el WV 0110. 000 000 0 r• SOWED res •m• 0a_e• TWA DR �an�..as 0 6^^ O . ,e....,.w•Me./WM 0 00 OM 0 Wee.WM 00. Ille 010011.• f011.01 OM 0 =CM, 0111. GENERAL NOTES Pe0C• 0.000 •• MY/0 011I0 WILY • etrefe• •1001.1 NW WWII MO WRAP 0 •14110, 0110110C110 110110.1.06 0.11 0•11,003 001 IV 0 10•404 00 PM. 0 1000ele 0000 •1100 0. COMO 110010. 000 W 1•01100• OP •1011W. 001•1•011,101 410,00 RAMC 1.0.0•1• COMWED DOOM OPPOO SOWN 00•0 DOOR DETAIL DO VI • 00 nalCCO Cm MP 0 &YAW IMAM 00:0 Car 11 ?MEL FRIARY o RIDDING o CGNWTRJCTICN = W INT1 VOW 14▪ .0 SAW PLAN - c -3450 S1-605 Per w. 4 IMMPTINT M. M. MN TIPMNID Ire MOT Dd.. car so NO MI.. ITT MN MI MEW Mil TY MTATIM call STMTOT IST4 1.61.40:0. MTV. MONA IT PAY. OMMT MT". INT TIMM /NO MT•4119 MO/IL UMMCTOT STri. MM. STIMPL LIT. MM. MGM WM. ECG MAIO 01.1110. ODIDO NCIVITT /MLitt, Mc.. LeXAM CMG S.001, MIM OMNI COMM 0.260•01,6 attifeLT20 non COLOR 11100910 COMICTO• MOAN MI, MTALL IMMO! NUJ Mi COMM TOM LEFT SIDE ELEVATION IMUMNITI 1.6.1 IIST.nalbo PET.. 00C. SYS{ WIC 61:0t TILMi to. cocoon ft RIGHT SIDE ELEVATION 1 - OW - •INNITM owe. from IhIRII9 re wen 000 MT TOOT 12CAIILIT 6,0101 Lellit MIME TINVIDMI MT COT TLAT TETIMMT MTMIT comm. Mb TO, REAR ELEVATION RXMO FRONT ELEVATION TOP 0 COME TT I OXII:MM OMB IM ISO 1 Mar IIII 1 q I = W J x w PPEL MART O MOMS ;T MOTS ORM M MIO.MSCLA MON. GOO MO DO • 1,10.1141112 COM .T PLM No. - cg -3480... MA IM 91-605 •ear Me 5