HomeMy WebLinkAboutSEPA EPIC-54-91 - CITY OF TUKWILA / PUBLIC WORKS - COMPREHENSIVE WATER PLAN (FIRE DISTRICT #1, FOSTER, THORNDYKE, RIVERTON AND CASCADE VIEW)Highline water district intertie
Water district 75 intertie
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COMPREHENSIVE WATER
PLAN UPDATE
(PUBLIC WORKS DEPT)
ANNEXATION AREAS, FIRE
DISTRICT N0. 1, FOSTER,
THORNDYKE, RIVERTON
AND CASCADE VIEW
EPIC 54 -91
A F F I D A V I T O F D I S T R I B U T I O N
Sylvia A. Osby hereby declare that:
fl Notice of Public Hearing
X ®Determination of Non -
significance
0 Notice of Public Meeting n Mitigated Determination of
Nonsignificance
OBoard of Adjustment Agenda
Packet and Scoping Notice
O Board of Appeals Agenda E Notice of Action
Packet
Determination of Significance
LiPlanning Commission Agenda fl Official Notice
Packet
Short Subdivision Agenda
Packet
fl Notice of Application for
Shoreline Management Permit
fl Shoreline Management Permit
Other
Other
was mailed to each of the following addresses on November 20, 1991.
Name of Project UPDATE TO COMPREHENSIVE
WATER PLAN
File Number EPIC -54 =91
Signature
r;� o f P' t 1'P�i "'a`� 'JS; a i
,�. rni i F � B IUa�QFd�we r wo, ' 'Y
CITY OF TUKWILA
6200 SOUTHCENTER BLVD.
TUKWILA, WA 98188
(206) 433 -1800
Water District # 125
P.O. Box 68147
Seattle, WA 98168
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CITY OF TUKWILA
6200 SOUTHCENTER BLVD.
TUKWILA, WA 98188
(206) 433 -1800
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I TO:
Seattle Water Department
710 Second Avenue, 10th Floor
Seattle, WA 98104
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CITY OF TUKWILA
6200 SOUTHCENTER BLVD.
TUKWILA, WA 98188
(206) 433 -1800
Washington State Dept. of Ecology
Environmental Review Section
Mail Stop PV -11
Olympia, WA 98504
t41 rd :.fir:
WAC 197 -11 -970
DETERMINATION OF NONSIGNIFICANCE
Description of Proposal An update to the Comprehensive Water Plan for base plan of the
City including the annexation areas, Fire District No. 1, Foster, Thorndyke, Riverton,
and Cascade View.
Proponent City of Tukwila Public Works Department_
Location of Proposal, including street address, if any E. annexation area: W. of Inter-
state Hwy. 5 & E. of Hwy. 599; Northern annexation area: N. of S. 112th Street. E.
Marginal Way, & Pacific Hwy. S.: Western annexation: later District No 125, District
No. 20 norther most dto of th C s de area. t
Lead Agency; Clty of [ukwila eFi1e No. tPU -54 -91
The lead agency for this proposal has determined that it does not have a probable
significant adverse impact on the environment. An environmental impact statement
(EIS) is not required under RCW 43.21C.030(2)(c). This decision was made after
review of a completed environmental checklist and other information on file with the
lead agency. This information is available to the public on request.
Q
There is no comment period for this DNS
This DNS is issued under 197 -11- 340(2). Comments must be submitted by
December 5, 1991 . The lead agency will not act on this
proposal for 15 days from the date below.
Responsible Official Rick Beeler
Position /Title Planning Director Phone 433 -1846
Address 6200 Southcenter Boulevard, Tukwila 98188
Date . , / Z-0 /' Signature
You may appeal this determination to the City Clerk at City Hall, 6200 Southcenter
Boulevard, Tukwila, WA 98188 no later than 10 days from the above date by written
appeal stating the basis of the appeal for specific factual objections. You may be
required to bear some of the expenses for an appeal.
Copies of the procedures for SEPA appeals are available with the City Clerk and
Planning Department.
FM.DNS
M E M O R A N D U M
TO: Jack Pace /Rick Beeler
th
FROM: Pat Brodin
DATE: October 16, 1991
SUBJECT: SUBMITTAL OF SEPA CHECKLIST FOR PREPARATION OF DNS
. TUKWILA WATER COMPREHENSIVE PLAN UPDATE - 88 -WTO1
•
Background - what, where, when, why
The Public Works Department is completing the update on the
1991 Comprehensive Water Plan. The plan has been prepared by
the consulting firm of Horton Dennis and Associates of
Kirkland. The proposal establishes a plan for water system im-
provements to assure adequate facilities for water consumption
and fire protection needs.
Issue Analysis - alternatives, costs, impacts
The Checklist is submitted for your review along with the plan.
This is a non - project proposal which has been through Tukwila's
interdepartmental review process.
Recommendation
The Public Works Department would like to adopt this plan be-
fore the end of 1991.
PB:PAB2:PACE MEM.doc
[T229OCT MINE
,1
CITY OF-TUKwiLA
PLANNING DEPT.
•
A. BACKGROUND
ENVIRONMENTAL CHECKLIST
1. Name of proposed project, if applicable:
Epp -69 -91
City of Tukwila
1991 Comprehensive Water System Plan, including Supplement A - Annexation Areas and
Supplement B - Technical Appendices.
2. Name of applicant:
City of Tukwila.
3. Address and phone number of applicant and contact person:
Ross Earnst, Director of Public Works
6300 Southcenter Blvd.
Tukwila, Washington 98188
(206) 433 -0179
4. Date checklist prepared:
October 14, 1991.
5. Agency requesting checklist:
City of Tukwila.
6. Proposed timing or schedule (including phasing, if applicable):
A suggested Capital Improvement Schedule is included in Chapter 5 of both the Base
Water System Plan and Supplement A - Annexation Areas. Specific timing of
improvements will depend on the availability of funding, scheduling of developer
extensions and water system demands.
7. Do you have any plans for future additions, expansion, or further activity related to or
connected with this proposal? If yes, explain.
Please refer to Chapter 5 of the plan and supplement for detailed information on future
improvements contemplated for the Tukwila water system. The water system plan does
not propose any land use expansions or changes and only considers the water system
improvements which are required to meet existing and projected water system demands.
8. List any environmental information you know about that has been prepared, or will be
prepared, directly related to this proposal.
None Known.
&INDEED
OCT 2.2 1991
CITY OF TUKwILA
PLANNING DEPT.
• •
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:
None Known.
10. List any government approvals or permits that will be needed for your proposal, if known.
State of Washington Department of Health Approval.
Depending on course of action taken in regard to service to some areas included in the
Skyway Critical Water Supply Service Area, amendment of the Skyway Coordinated Water
System Plan may be required. See Supplement A - Annexation Areas for further
discussion on this area of the City.
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. (Lead
agencies may modify this form to include additional specific information on project description.)
This proposal contemplates the adoption of the City of Tukwila 1991 Comprehensive
Water System Plan, with Supplement A - Annexation Area and Supplement B - Technical
Appendices. These documents address future water service to all areas of the existing
Tukwila city limits and propose a capital improvements schedule for system improvements
in accordance with water system demand projections developed as part of the Plan.
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 applications related to this
checklist.
The City of Tukwila is generally located south of the City of Seattle, east of the City of
Sea Tac and west of the City of Renton as indicated on Figure 1 -1 of the Plan. The City
is within all or part of the following Sections: Section 33, Township 24 North; and,
Sections 3, 4, 9, 10, 14, 15, 22, 23, 24, 25, 26, 35, and 36, Township 23 North, Range
4 East.
B. ENVIRONMENTAL ELEMENTS
1. Earth
a. General description of the site (circle one): Flat, rolling, hilly, steep slopes,
mountains, other
Topography of the area is characterized by the, flat topography of the Duwamish
River Valley floor, with slopes leading up to a plateau in the western portion of
the City.
• •
b. What is the steepest slope on the site (approximate percent slope)?
Not Applicable.
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.
The majority of the area consists of alluvial soils composed of silt, clay and some
peat with some bedrock outcroppings.
d. Are there surface indications or history of unstable soils in the immediate vicinity?
If so, describe.
Unstable soils may occur along the banks of the Duwamish River or in steep
slopes leading to the valley floor.
e. Describe the purpose, type, and approximate quantities of any filling or grading
proposed. Indicate source of fill.
Not Applicable.
f. Could erosion occur as a result of clearing, construction, or use? If so, generally
describe.
Not Applicable.
g. About what percent of the site will be covered with impervious surfaces after project
construction (for example, asphalt or buildings)?
Not Applicable.
h. Proposed measures to reduce or control erosion, or other impacts to the earth, if any:
Not Applicable.
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.
Not Applicable.
b. Are there any off -site sources of emissions or odor that may effect your proposal?
If so, generally describe.
Not Applicable.
c. Proposed measures to reduce or control emissions or other impacts to air, if any:
Not Applicable.
•
3. WATER
a. Surface:
1) Is there any surface water body on or in the immediate vicinity of the site
(including year -round and seasonal streams, saltwater, lakes, ponds, wetlands)?
If yes, describe type and provide names. If appropriate, state what stream or
river it flows into.
The Green- Duwamish River flows through the City of Tukwila as indicated on the
maps included in the Plan. Other small streams are within the city limits. This
proposal does not impact any surface waters.
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 to wetlands and indicate the area of the site that
would be affected. Indicate the source of fill material.
Not Applicable.
4) Will the proposal require surface water withdrawals or diversions? Give
general description, purpose, and approximate quantities if known.
No.
5) Does the proposal lie within a 100 -year floodplain? If so, note location on
the site plan.
Not Applicable. This proposal does not contemplate any activity relating to
floodplains.
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.
b. Ground
1) Will ground water be withdrawn, or will water be discharged to ground
water? Give general description, purpose, and approximate quantities if known.
No.
2) Describe waste material that will be discharged into the ground from septic
tanks or other sources, 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.
• •
c. Water Runoff (including storm water):
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.
Not Applicable.
2) Could waste materials enter ground or surface waters? If so, generally
describe.
Not Applicable.
d. Proposed measures to reduce or control surface, ground, and runoff water impacts,
if any:
Not Applicable.
4. PLANTS
a. Check or circle types of vegetation found on the site:
X deciduous tree: alder, maple, aspen, other
X evergreen tree: fir, cedar, pine, other:
X shrubs,
X grass
X pasture
crop or grain
X wet soil plants: cattail, buttercup, bulrush, 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?
None.
c. List threatened or endangered species known to be on or near the site.
None Known.
d. Proposed landscaping, use of native plants, or other measures to preserve or enhance
vegetation on the site, if any:
Not Applicable.
5. ANIMALS
a. Circle any birds and animals which have been observed on or near the site or are
known to be on or near the site:
birds: hawk, heron, eagle, songbirds, other:
mammals: deer, bear, elk, beaver, other:
fish: bass, salmon, trout, herring, shellfish, other:
• •
b. List any threatened or endangered species known to be on or near the site.
None Known.
c. Is the site part of a migration route? If so, explain.
Puget Sound Flyway.
d. Proposed measures to preserve or enhance wildlife, if any:
Not Applicable.
6. ENERGY AND NATURAL RESOURCES
a. What kinds of energy (electric„ natural gas, oil, wood stove, solar) will be used to
meet the completed project's energy needs? Describe whether it will be used for heating,
manufacturing, etc.
Operation of the Tukwila water system requires the use of electricity and water.
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:
Recommendations for development of water conservation program have been
included in the Plan.
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.
No.
1) Describe special emergency services that might be required.
None Required.
2) Proposed measures to reduce or control environmental health hazards, if any:
None Required.
b. Noise
1) What types of noise exist in the area which may affect your project (for
example: traffic, equipment, operation, other)?
Not Applicable.
• •
2) What types of levels of noise would be created by or associated with the
project on a short -term or a long -term basis (for example: traffic, construction,
operation, other)? Indicate what hours noise would come from the site.
None.
3) Proposed measures to reduce or control noise impacts, if any:
None Required.
8. LAND AND SHORELINE USE
a. What is the current use of the site and adjacent properties?
The existing land use of the area is identified in Chapter 2 of the Base Plan and
Supplement A - Annexation Areas. As indicated, land use within the City of
Tukwila ranges from single and multi family residential uses to Boeing Field
airfield. Southcenter Shopping Center is a regional shopping area located in the
heart of Tukwila. Other commercial, industrial and warehouse uses also exist in
the Southcenter area.
b. Has the site been used for agriculture? If so, describe.
Not Applicable.
c. Describe any structures on the site.
Not Applicable.
d. Will any structures be demolished? If so, what?
No.
e. What is the current zoning classification of the site?
Zoning is consistent with land use and is identified in Chapter 2 of the Base Plan
and Supplement A.
f. What is the current comprehensive plan designation of the site?
Please refer to Chapter 2 of the Base Plan and Supplement A. Comprehensive
Plan designations reflecting the diverse land uses within the City are
appropriately assigned.
g. If applicable, what is the current shoreline master program designation of the site?
Not Applicable.
h. Has any part of the site been classified as an "environmentally sensitive" area? If so,
specify.
Sensitive areas are identified by the City of Tukwila Department of Community
Development. This Comprehensive Water System Plan will not impact such
areas.
• •
i. Approximately how many people would reside or work in the completed project.
Not Applicable.
j. Approximately how many people would the completed project displace?
None.
k. Proposed measures to avoid or reduce displacement impacts, if any:
Not Applicable.
1. Proposed measures to ensure the proposal is compatible with existing and projected
land uses and plans, if any:
This Comprehensive Water System Plan was developed to address the future water
system needs of the City of Tukwila based on existing and projected land use
patterns and associated water consumption and fire protection requirements.
9. HOUSING
a. Approximately how many units would be provided, if any? Indicate whether high,
middle, or low- income housing.
None.
b. Approximately how many units, if any, would be eliminated? Indicate whether high,
middle, or low- income housing.
None.
c. Proposed measures to reduce or control housing impacts, if any:
Not Applicable.
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?
Not Applicable.
b. What views in the immediate vicinity would be altered or obstructed?
None.
c. Proposed measures to reduce or control aesthetic impacts, if any:
Not Applicable.
• •
11. LIGHT AND GLARE
a. What type of light or glare will the proposal produce? What time of day would it
mainly occur?
None.
b. Could light or glare from the finished project be a safety hazard or interfere with
views?
Not Applicable.
c. What existing off -site sources of light or glare may affect your proposal:
Not Applicable.
d. Proposed measures to reduce or control light and glare impacts, if any:
Not Applicable.
12. RECREATION
a. What designated and informal recreational opportunities are in the immediate vicinity.
Not Applicable.
b. Would the proposed project displace any existing recreational uses? If so, describe.
No.
c. Proposed measures to reduce or control impacts on recreation, including recreation
opportunities to be provided by the project or applicant, if any:
Not Applicable.
13. HISTORIC AND CULTURAL PRESERVATION
a. Are there any places or objects listed on, or proposed for, national, state, or local
preservation registers known to be on or next to the site? If so, generally describe.
Not Applicable.
b. Generally describe any landmarks or evidence of historic, archaeological, scientific,
or cultural importance known to be on or next to the site.
Not Applicable.
c. Proposed measures to reduce or control impacts, if any:
Not Applicable.
•
14. TRANSPORTATION
•
a. Identify public streets and highways serving the site, and describe proposed access to
the existing street system. Show on site plans, if any.
See Figure 1 -1 and 2 -1 of the Base Plan and Supplement A - Annexation Areas.
Interstate Highways 5 and 405, the BNSF Burlington Northern Railroad, and State
Route 99 bisect the City.
b. Is site currently served by public transit? If not, what is the approximate distance to
the nearest transit stop?
Not Applicable.
c. How many parking spaces would the completed project have? How many would the
project eliminate?
None.
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.
None.
g. Proposed measures to reduce or control transportation impacts, if any:
Not Applicable.
15. PUBLIC SERVICES
a. Would the project result in an increased need for public services (for example- fire
protection, police protection, health care, school, other)? If so, generally describe.
No.
b. Proposed measures to reduce or control direct impacts on public services, if any.
Not Applicable.
• •
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 service,
and the general construction activities on the site or in the immediate vicinity which might
be needed.
This proposal establishes a plan for the future development of water systems
within the City of Tukwila and assures that adequate facilities are provided for
water consumption and fire protection needs.
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 d ision.
Signature:
Date Submitted:
D. SUPPLEMENTAL SHEET FOR NONPROJECT ACTIONS
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?
No Increases.
Proposed measures to avoid or reduce such increases are:
Not Applicable.
2. How would the proposal be likely to affect plants, animals, fish or marine life?
No Impacts.
Proposed measures to protect or conserve plants, animals, fish or marine life are:
None Necessary.
3. How would the proposal be likely to deplete energy or natural resources?
Construction of new water facilities will require the use of construction materials typical to this
type of construction.
Proposed measures to protect or conserve energy or natural resources are:
Efficient planning and design of utilities and implementation of a water conservation program in
accordance with the recommendations of the Plan will assist in conservation of water and
energy.
4. How would the proposal be likely to use or affect environmentally sensitive areas or areas
designated (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 primelands?
This proposal will not impact any of the above listed areas.
Proposed measure to protect such resources of to avoid or reduce impacts are:
Any future work done on the Tukwila water system will be consistent with the regulations and
policies governing the protection of such resources.
5. How would the proposal be likely to affect land and shoreline use, including whether it would
allow or encourage land or shoreline uses consistent existing plans?
This proposal will not affect, allow or encourage land and shoreline uses.
Proposed measures to avoid or reduce shoreline and land use impacts are:
Not Applicable.
• •
6. How would the proposal be likely to increase demands on transportation or public services
and utilities?
This proposal will not impact demands on transportation or public utilities but will provide a
guideline for future development of the City's water system.
Proposed measures to reduce or respond to such demands are:
Not Applicable.
7. Identify, if possible, whether the proposal may conflict with Local, state or federal laws
requirements for the protection of the environment.
This proposal is not in conflict with any such laws.
CITY . OF TUKWILA fli
OFFICE OF COMMUNITY DEVELOPMENT
XXXXXXFX PROPOSED
DECLARATION OF NON - SIGNIFICANCE
Description of proposal
Comprehensive Water Plan
City of Tukwila
Location of Proposal
Lead Agency
Tukwila Planning Area
City of Tukwila, WAC 197 -10 -205
File No. EPIC - 198 -82
This proposal has been determined to 5X/not have) a significant
adverse impact upon the environment. An EIS P( /is not) required
under RCA' 43.21C.030(2)(c). This decision was made after review
by the lead agency of a completed environmental checklist and other
information on file with the lead agency.
Responsible Official
Position /Title
Brad Collins
Planning Director
Signature
CCt
This Declaration of Non - Significance applies only to the legislative act of
adopting the Comprehensive Water Plan. Separate environmental assessment
shall be conducted for any project which implements the Comprehensive Water
Plan.
MEOWED
OCT 2 2 1991
CITY OF TUKwiLA
PLANNING DEPT.
•
APPENDIX V
CITY OF TUKWILA
RESOLUTION NO. 67,3
A RESOLUTION OF THE CITY OF TUKWILA, WASHINGTON,
ENACTING A COMPREHENSIVE WATER PLAN.
WHEREAS, the City of Tukwila is a municipal corporation formed
under and with duties imposed under the provisions of Chapter 35A of the
Revised Code of Washington, and
WHEREAS, the City Council of Tukwila has deemed it desirable
to adopt a Comprehensive Water Plan as required by WAC Chapter 248.54.
NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF TUKWILA,
WASHINGTON, DO RESOLVE AS FOLLOWS:
•
1. That certain document entitled "Comprehensive Water Plan"
of City of Tukwila, King County, Washington, dated March, 1982, as drafted,
promulgated and proposed by Horton Dennis and Associates, Inc., Engineers,
is herein incorporated by this reference as if set forth in full at this
point.
2. The document immediately hereinabove described and incor-
porated by reference is adopted as the Comprehensive Water Plan for City
of Tukwila, effective this date, to assess the existing conditions, estab-
lish general goals, project future system -wide needs and identify opportuni-
ties to solve anticipated problems and provide a basis for inter- govern-
mental coordination, management and planning. The plan is explicitly de-
signed to be revised periodically to reflect changes in the City's capital
improvement program.
3. Said Comprehensive Plan is tentatively determined to not
have a significant adverse impact upon the environment, and the Planning
Director of the City is hereby directed to prepare a decla-
ration of significance/non-significance, in the form provided by WAC
197 -10 -355 and to maintain and file said declaration as required by said
regulation.
PASSED BY THE CITY COUNCIL OF THE CITY OF.TUKWILA, WASHINGTON,
at a regular meeting thereof this - day of =� , 1983.
ybr�
Approved as to Form
ATTEST:
�L/ '
ttorney Jeff C: Wishko
Ciy� r .
l
Horton Dennis & Associates .
Consulting Engineers, Planners & Surveyors
320 Second Avenue South
Kirkland Washington
CITY OF TUKWILA
COMPREHENSIVE WATER SYSTEM PLAN
SUPPLEMENT A - ANNEXATION AREAS
June 1991 •
PREPARED BY:
Horton Dennis & Associates
Consulting Engineers, Planners & Surveyors
320 Second Avenue South
Kirkland Washington
IMRE
OCT 221991
CITY OFTuacwu.A
PLANNING DEPT.
CITY OF TUKWILA
• COMPREHENSIVE WATER PLAN
SUPPLEMENT A - ANNEXATION AREAS
TABLE OF CONTENTS
CHAPTER 1 - INTRODUCTION
PAGE NO.
Authorization 1 -1
Location 1 -1
Authority 1 -2
Planning Goals and Objectives 1 -3
CHAPTER 2 - PLANNING CONSIDERATIONS AND SERVICE AREA CHARACTERISTICS
Background 2 -1
Planning Area 2 -1
Related Plans and Policies 2 -1
Existing Water Service Areas 2 -1
Future Service Areas 2-4
Agreements 2-6
Physical Features of the Water Service Area 2 -7
Topography 2 -7
Geology and Soils 2 -7
Surface Water Resources 2 -8
Human Environment 2 -9
Land Use Calculations 2 -9
Population 2 -17
Land Development Potential 2 -17
Growth Management Scenarios 2 -20
CHAPTER 3 - EXISTING WATER SYSTEM
Introduction - 3 -1
City of Seattle 3 -1
King County Water District No. 125 3 -3
King County Water District No. 20 3 -5
Creston Water Association 3 -7
City of Tukwila 3 -7
CHAPTER 4 - DESIGN CRITERIA AND SERVICE REQUIREMENTS
Design Criteria 4 -1
Water Supply and Demand 4 -1
Water System Storage 4 -5
CHAPTER 5 - RECOMMENDED SERVICE AREAS AND IMPROVEMENTS
Introduction 5 -1
East Annexation Area 5 -1
Northern Annexation Area 5 -3
Western Annexation Area 5 -3
Water System Storage 5-4
Water Lines 5 -5
CHAPTER 6 - IMPLEMENTATION
Introduction 6 -1
Service Areas and Interlocal Agreements 6 -1
Financial Considerations 6-2
LIST OF FIGURES
FIGURE PAGE NO.
1 -1 Vicinity Map 1 -3
1 -2 Location Map 1-4
2 -1 Water Service Areas 2 -2
2 -2 SKYWAY CWSP Recommended Service Areas 2 -5
2 -3 Physiographic Features 2 -8'
2-4 Soil Groups 2 -9
2 -5 Comprehensive Land Use Policy Map 2 -14
2-6 Zoning Map 2 -15
2 -7 Existing Conditions 2 -21
2 -8 Vacant Land Buildout 2 -22
3 -1 Seattle Supply System 3 -2
LIST OF TABLES
TABLE PAGE NO.
2 -1 Soil Characteristics 2 -10
2 -2 Land Use Categories 2 -16
2 -3 Land Use and Population 2 -17
2-4 Vacant Land by Zone Classification 2 -18
2 -5 Employee Densities 2 -19
2-6 Projected Development Scenarios 2 -20
4 -1 Summary of Minimum Design Criteria 4 -2
City of Tukwila Comprehensive Water Plan 4 -3
4 -2 Recommend Average Daily Water Consumption
for Tukwila 4 -3
4 -3 Design Peaking Factors for Tukwila Water System 4 -3
4-4 City of Tukwila Annexation Areas
Projected Average Daily Water Use 4-4
4 -5 Minimum Storage Requirements 4-6
5 -1 Proposed Water Improvements for
Annexed Areas of Tukwila t 5 -8
6 -1 Water Rate Comparison 6 -3
CHAPTER 1
INTRODUCTION
CHAPTER 1
INTRODUCTION
Authorization
This report compiles and summarizes the results and conclusions of planning and engineering studies
performed by Horton Dennis & Associates in developing a comprehensive water plan for the recently
annexed areas of the City, including Fire District No. 1, Foster, Thorndyke, Riverton and Cascade View.
This supplement addresses the study area boundaries, population and employment statistics, the current
providers of water service to the area, development plans and zoning, minimum design criteria, and
existing water system(s). It also assesses the adequacy of existing water systems, recommends
improvements and considers the feasibility and desire of the City to take over service to the annexed
areas.
This report is authorized as a supplement to the City's 1990 Comprehensive Water Plan. Maintaining a
separate supplement provides the City the flexibility to separate the water system requirements for various
areas. It also provides a more focused approach to defining and evaluating the existing systems and needs
of the newly annexed areas.
This document is intended to be used in conjunction with the City's general 1990 Comprehensive Water
Plan and Supplement B - Technical Data. Information contained in the general plan and supplement will
be referenced as such, and not repeated herein. This includes such water system plan requirements as
developers extension standards, water conservation programs, operation and maintenance programs, SEPA
compliance, etc.
Location
The City of Tukwila recently experienced five major annexations which are referred to as Fire District
No. 1, Riverton, Foster, Thorndyke and Cascade View. This supplement specifically addresses these five
areas. The annexed area expanded the corporate limits of the City to the north and west. The City now
extends to State Route 99 (Pacific Highway South) from South 160th Street to about South 153rd Street,
where the boundary follows the Military Road and the Pacific Highway South again to the Duwamish
River, where the boundary continues north along the River to Boeing Field. The new northeastern city
boundary follows the Seattle city limits south to about South 120th Street.
1 -1
Specifically, the geographic areas of each of the five annexation areas are as follows. Fire District No.
1 is generally bounded on the west by the Duwamish River, on the north by the City of Seattle, on the
east by the City of Seattle and the Burlington Northern Railroad tracks, and on the South by the City of
Renton. The Riverton area extends from the Duwamish River to South 138th Street and is east of Pacific
Highway South. Foster is between South 138th Street to South 144th Street and east of Pacific Highway
South. Thorndyke is the southern portion of the annexation area, extending from South 144th Street to
South 160th Street between I -5 and Pacific Highway South. Finally, the Cascade View area is between
Pacific Highway South and Military Road from approximately South 152nd Street north to South 128th
Street, then along Pacific Highway South to the Duwamish River. Figures 1 -1 and 1 -2 indicate the
annexed areas and their relationship to the pre- annexation City boundaries.
Authority
Under RCW Chapter 35.13A a city may choose whether or not to assume water district responsibilities
for areas it annexes. The primary objective in preparing this report and evaluating the existing facilities
within the annexation area is to ensure that adequate water service is being provided to all areas within
the current city limits. The work associated with preparing this document was authorized by a contract
between the City of Tukwila and Horton Dennis & Associates.
Planning Goals and Objectives
The purpose of this report is to meet the goals and objectives of the Comprehensive Land Use Policy Plan
cited in the main body of the 1990 Comprehensive Water Plan. Again, the primary focus of this report
is to define the level of water service within the annexation area and ensure that adequate service is being
provided. The City may or may not actually assume water service responsibilities for the newly annexed
areas in the near future. Takeover of existing facilities may not be in the best interest of the customers,
the City or existing purveyors for a number of years, in which case a gradual assumption of facilities may
be more feasible.
1 -2
LK. SAMMAMISH
ANNEXATION
:STUDY AREA
RENTON
TUKWILA
S MOI NE
• KENT
•
ISSAQUAH
LK. YOUNGS
PRE - ANNEXATION TUKWILA
CITY LIMITS
• AUBURN
KING CO.
PIERCE CO
NTS
UIDR1
HORTON DENNIS & ASSOCIATES, INC.
CONSULTING ENGINEERS, PLANNERS
& SURVEYORS
Kirkland, WA 98033-6687 (206) 822-2525
Pro'. No.5030.06I Drwn. MAA Ioate 5 -31 -91
FIGURE 1 -1
VICINITY MAP
i
I
1HDD1
CITY OF
SEATTLE
FIGURE 1 -1_,
LOCATION MAP
Legend
•
j/.
IIUIIUI
ANNEXATION STUDY
AREA BOUNDARY
FIRE DISTRICT 1 ANNEXATION
RIVERTON ANNEXATION
FOSTER ANNEXATION
THORNDYKE ANNEXATION
CASCADE VIEW ANNEXATION
CITY OF SEATTLE
KING COUNTY
KING COUNTY .
CITY OF SEA -TAC
2000 1000 0 2000
SCALE IN FEET
TUKWILA
CITY
LIMITS
i
0
V
City of Tukwila
COMPREHENSIVE WATER PLAN: SUPPLEMENT A - ANNEXATION AREAS
CHAPTER 2
PLANNING CONSIDERATIONS AND
SERVICE AREA CHARACTERISTICS
CHAPTER 2
PLANNING CONSIDERATIONS AND SERVICE AREA CHARACTERISTICS
Background
This supplement pertains only to the areas recently annexed to the City of Tukwila, including: Fire
District Number 1, Riverton, Foster, Thorndyke and Cascade View. These areas were swept by a strong
wave of annexations that took place in 1989 and nearly doubled the land area of Tukwila from 2,880 acres
to approximately 5,513 acres. In conjunction with these major annexations, the population significantly
increased from 4,760 to 14,631 persons.
Planning Area
The planning area for this study includes the four recently annexed areas to the City of Tukwila. Namely,
they are Fire District Number 1, Foster, Thorndyke, Riverton and Cascade View. The locations of these
areas are described in Chapter 1 of this report and are shown in Figures 1 -1 and 1 -2.
Related Plans and Policies
Related policies considered as part of the overall development of the City's Water System Plan are
discussed in Chapter 2 of the main body of this report. Plans specifically applicable to this annexation
supplement include the Comprehensive Water System Plans of King County Water District Nos. 125 and
20, adopted in 1985 and 1988 respectively. These documents were used for the development existing
service area and system data contained in this document. Currently, there are no conflicts between this
Plan and the District's Comprehensive Plans, although future service area decisions may impact the
Districts' service area and facilities.
Existing Water Service Areas
As indicated in Figure 2=1, the study area is currently served by several water purveyors, including the
City of Seattle, King County Water District No. 125, King County Water District No. 20, the Creston
Water Association, and the City of Tukwila.
Figure 2 -1 shows the existing legal boundaries and actual water service areas of other water purveyors
providing service to the annexation area. A review of these service areas in conjunction with the existing
water system facilities of other water purveyors indicates that the majority of the annexation area is
2 -1
4,
FIGURE 2 -1
-y
W
WATER SERVICE
`4 AREAS
CITY OF
SEATTLE
Legend
V
TUKWILA
CITY
LIMITS
ANNEXATION STUDY
AREA BOUNDARY
CITY OF TUKWILA
WATER DISTRICT 125
WATER DISTRICT 20
SEATTLE MUNCIP.M WATER
CRESTON WATER ASSOCIATION
CITY OF SEATTLE
KING COUNTY
9. 126TH 8r.
IA), 3.
2000 1000
9. 138TH
KING COUNTY
RENTON
CITY OF SEA —TAC
0
SCALE IN FEET
LJIDFI1
2000
TUKWILA
CITY
LIMITS
SR 518
8. 180TH 8T.
c
N
City of Tukwila
COMPREHENSIVE WATER PLAN: SUPPLEMENT A — ANNEXATION AREAS
currently served adequately by others. Exceptions to this are in the Allentown and Foster Point areas and
a portion of Empire Hill, where the City recently assumed water service responsibilities from the now
defunct Waster District No. 25 and significant system improvements are required. The service areas of
other purveyors within the area are generally described as follows:
The City of Seattle provides service to the northern portion of the annexation area, including
industrial connections along East Marginal Way South and a portion of the residential area on
Empire Hill.
King County Water District No. 25 was responsible for water service to the Allentown and Foster
Point areas, as well as a portion of the Empire Hill area, until May 20, 1991. On that date the
King County Boundary Review Board approved dissolution of the District and assumption of
service responsibilities by the City of Tukwila. The Tukwila City Council also approved takeover
of the Water District on that date. Appendix A to this supplement discusses the dissolution and
takeover of the District as well as system improvements required in this area of the City.
King County Water District No. 20 provides water service to several connections in the
northwesternmost portion of the Cascade View annexation area.
The Creston Water Association is a water cooperative providing water service to approximately
15 connections in the vicinity of 47th Avenue South and South Ryan Way, on Empire Hill. The
Association purchases its water from the City of Seattle. By agreement, any new services in this
area will be connected to the City of Seattle's existing water system. In addition, as ownership
of homes currently connected to the system change, services will be transferred to Seattle.
King County Water District No. 125 serves the remainder of the annexation area, including
Foster, Thorndyke, Riverton and the majority of Cascade View. In addition, Water District No.
125 serves a few connections on Foster Point. The City and Water District No. 125 are currently
negotiating an interlocal agreement providing for the transfer of these few Foster Point
connections to the City of Tukwila.
2 -3
Future Service Areas
Although the City's ultimate service area will likely include the entire study area addressed by this
supplement to the City's 1990 Comprehensive Water Plan, water service to the annexation area in the
immediate future will be by a combination of the above purveyors and the City of Tukwila. The
SKYWAY Coordinated Water System Plan addresses future water service to the eastern portion of the
annexation area as indicated on Figure 2 -2. A discussion of the boundary adjustments and interlocal
agreements required in conjunction with these recommended service area is presented below. Specific
system changes and required improvements associated with the redefinition of service areas is presented
in Chapter 5 of this supplement.
To achieve the service areas recommended by the CWSP, takeover of King County Water District No.
25 by the City of Tukwila was required. As mentioned, takeover of Water District No. 25 has been
accomplished and, at least initially, the City intends to provide water service to all existing Water District
No. 25 connections. In accordance with the SKYWAY Coordinated Water System Plan, service to
Allentown and Foster Point will be provided by the City of Tukwila in the future.
In addition, the City may wish to provide future water service to that portion of Empire Hill which is
within the city limits. This area is currently served by the City of Tukwila (via the Water District No.
25 takeover), the City of Seattle and the Creston Water Association. The SKYWAY CWSP recommends
future service to the area by the City of Seattle, which would require an interlocal agreement between the
two cities in order for Seattle to provide water to customers within the Tukwila city limits. The City
of Tukwila has initiated discussions with the City of Seattle to identify Seattle's policies regarding
provision of water service within the limits of another city and to determine the best alternative for service
to this area of Tukwila. Both parties are in agreement that both sewer and water service to this portion
of Empire Hill should be provided by one party or the other. Until an agreement is reached regarding
future service to the entire area, Tukwila will assume responsibility for service to Water District No. 25
customers in the area. If it is determined that Tukwila will serve the entire area in the future, an
amendment to the SKYWAY CWSP will be required. If the City of Tukwila were to assume responsibility
for existing Creston Water Association connections, a similar amendment to the SKYWAY CWSP will
be required.
Similarly, the City of Tukwila has assumed initial responsibility for service to the area of Water District
2-4
•1
•
c`'rN\� . , r} a�, • u. 11 i�PUliir 11/ .t/ (r-fN • � ` `: 'D ::liinl'Ji! ..
A.M.! ii !
No. 25 which is west of the Duwamish River and referred to as the Quarry area of Water District No.
25. Future service to this area may be by contract with Water District No. 125, as recommended in the
SKYWAY CWSP or directly by the City of Tukwila. Because replacement of the entire system in this
area is required, it may not be in the best interest of Water District No. 125 to assume full responsibility
for the area. Consideration alternatives for service to the Quarry area by Water District No. 125 will be
given as a future study and, if required, an amendment to this Plan.
The City of Seattle also serves the northern portion of the Fire District No. 1 Annexation area, along East
Marginal Way South. Although this is considered a separate issue from the Empire Hill service area
question, Tukwila and Seattle are also negotiating an agreement for future service to this area. Transfer
of services to the City of Tukwila and subsequent improvements associated with service to this area are
discussed in Chapter 5 of this supplement.
Service the remainder of the area is provided by King County Water District's No. 125 and 20 is
currently adequate, and the City does not propose takeover of service to these areas at this time. This
is subject to change, however, especially in the area served by King County Water District No. 125.
Water District No. 125 currently provides service to areas within the City of Sea Tac and the City of
Tukwila. If the City of Sea Tac pursues its authority to takeover Water District No. 125 services within
Sea Tac, the City of Tukwila will.likely assume responsibility for services within the Tukwila City limits.
Agreements
Intertie agreements exist between the City of Tukwila and the adjacent purveyors including Water District
Nos. 25 and 125. Copies of these agreements are on file with the City. The City maintains two intertie
agreements with Water District No. 125 for facilities located at South 131st Place and 44th Avenue South
(6 -inch) and at Interurban Avenue South and 52nd Avenue South 4- inch). Upon takeover of the Water
District No. 125 customers in the vicinity of the Interurban Avenue South intertie as discussed in the main
body of this Plan), this backup connection will no longer be necessary since the entire area will be served
by Tukwila. An additional intertie with Water District No. 125 is located at South 144th Street and 53rd
Avenue South.
As discussed above additional interlocal agreements between Tukwila and potential water purveyors within
the City limits are in progress. The City will also require franchise agreements with each purveyor
2-6
operating utilities within City of Tukwila right -of -ways. Such agreements will include provisions for
review and approval of water system projects proposed within the city limits in order to insure compliance
with Tukwila minimum design standards and provide for future combination of systems.
Physical Features of the Water Service Area
Topography, geology, soils, surface and ground water resources and the associated flood plains are
important for consideration in the future development of the area. These factors are generally discussed
below. Figure 2 -3 generally illustrates the basic physical features of the study area. Detailed information
on sensitive areas should be obtained from the City's Department of Community Development.
Topography
Topography of the annexation area is shown on the Existing and Proposed Water System Maps
provided with the main body of the 1990 Water System Plan. The area can generally be
classified as hilly with some steep slopes leading to the Duwamish River valley floor. Steep
slopes have been identified on the City's Sensitive Areas Maps and occur in the Empire Hill area,
north of the Duwamish River in the northern portion of Allentown, along both sides of Pacific
Highway South and along the Interstate 5 and Highway 518 corridors.
Geology and Soils
The geology of the Duwamish River Basin consists of sedimentary and volcanic bedrock, glacial
deposits of various ages and types, and alluvium in the valley bottoms. Till is found along most
of the highlands and generally caps the drumlin hills. Recessional outwash sand is interspersed
throughout the till and is commonly found along shallow stream valleys and other depressional
areas. Landslide deposits exist within steep - walled tributary valleys. Recent alluvium, composed
of gravel, sand and silt fills the Duwamish Valley and the bottom of the tributary valleys.
The majority of the annexation area is composed of alluvial and till soil types similar to the soil
types found in the remaining Tukwila planning area as indicated on Figure 2 -4 and described in
Table 2 -1. Alluvial soils are primarily found adjacent to the Duwamish River north to Boeing
Field (Fire District No. 1). Alluvial soils are mostly unconsolidated silt, sand and gravel valley
fill with some clay. It also includes artificial fill and peat. These soils have two severe
2 -7
ILIIN• . IL n re...1_ I ...we, e • ft n •
x
1-
A
CITY OF
SEATTLE
FIGURE 2 -3
PHYSIO GRAPHI C 'AREAS
Legend
2000 1000
C.
TUKWILA
CITY
LIMITS
4
0
ANNEXATION STUDY
AREA BOUNDARY
LOWLAND
VALLEY WALL
PLATEAU
CITY OF SEATTLE
KING COUNTY
S. 12STH ST.
'Q JR.
w�1 Y
0
S. 13STH
$ S. 140TH ST.
S. 144TH ST.
KING COUNTY
CITY OF SEA -TAC
0
2000
SCALE IN FEET
RENTON
TUKWILA
CITY
UMITS
1I' SR 518
q
0
4
0
S. 1SOTH ST.
I
1
1
1
1
1
1
1
1
1
I ..
1
City of Tukwila
COMPREHENSIVE WATER PLAN: SUPPLEMENT A - ANNEXATION AREAS
HDA 5030F2 -4.DWG 8-18 -91
;.._ \ FIGURE 2 -4
o,
iii��� ;Ire
CITY OF
SEATTLE
2000 1000
ty
tri
TUKWILA
CITY
UMITS
9
SOIL GROUPS
Legend
ANNEXATION STUDY
AREA BOUNDARY
ALLUVIALS SOILS
OUTWASH SOILS
TILL SOILS
BEDROCK ROCK
' "OUTCROPPINGS
CITY OF SEATTLE
KING COUNTY
8. 128TH
R.
Ay 8.
c
O
8. 168TH 8T
KING COUNTY
RENTON
CITY OF SEA -TAC
0
SCALE IN FEET
2000
TUKWILA
CITY
UMITS
!" " SR 518
a 8. 18OTM 8T.
"i
V >
C3 °c
Y
City of Tukwila
COMPREHENSIVE WATER PLAN: SUPPLEMENT A - ANNEXATION AREAS
1992 Expenditures
Southcenter Park Way Signals $150,000
Retain Southcenter PkWy /Strander which has safety and
capacity improvements being designed for 1992 construc-
tion; postpone the S 168 St intersection and driveway
consolidation intersection projects.
Ped Path Program $450,000
Spread the work over more years - reducing the 1992 and
1993 expenditures. 1992 locations will be based on the
residential street ratings, locations previously de-
signed, and new safety /problem issues such as 35 Ave S
and Interurban.
Gilliam Cr Tr & Fish Enhancement $0
Complete the 1991 design report, postpone trail and
creek enhancement PS &E and begin construction phases in
1994.
Waste Dirt Displacement Facility $150,000
Obtain a facility for street sweepings to be disposed,
recycled and separated to minimize hazardous waste dis-
posal costs, street sweeping disposal travel costs, etc.
Decant /sludge drying station $100,000
Construct a decant station to dispose of storm sewer,
shop, and other effluentsand sludge per EPA /DOE re-
quirements.
Southgate /Foster Cr Fish Enhancement $50,000
Complete PS &E in 1992 and construction in 1993.
Riverton Cr Enhancements $75,000
Design Report identifying enhancements and mitigation
participation costs.
Intersection Improvement Program $400,000
Complete PS &E and construct Andover Pk E /Minkler and
Andover Pk E /Tukwila Pk Wy in 1992; complete PSE on Pa-
cific Hwy /S 130 St in 1992 and construct in 1993 (All
are safety improvements.
Pacific Hwy (BAR -116 & 116 -152) $280,000
Complete design report for frontal improvements, grant
pursuit, and scheduling construction in phases.
Repairs & Overlay $750,000
Reduce the program; designing and constructing Strander,
Interurban (S 139 St - Southcenter Blvd), and highest
need annexation area streets (to be rated).
Rockery Program $0
Postpone to 1994, 5, & 6.
Bridge Program $150,000
Design report and PS &E for bridge(s) determined as high-
est need from study currently in progress. PS &E pro-
vides a headstart on any future federal bridge funding.
S 133 St (Interurban - 130th) $0
Postpone to combine with S 134 St work in in 1994 & 5;
coordinating with Southgate Fish enhancement work.
Minkler $0
Postpone design update work to 1995
40 - 42 & S 152 St $825,000
Continue with design report, complete PS &E in late 1992
and start major construction (still phased to 1997);
1993 and 1994 expenditures scheduled at $825,000 and
$1,600,000. Move entire project to Residential Streets.
Multimodal Center $0
Deferr work to Metro federally funded studies.
Signal Controllers and upgrades $110,000
Continue signal controller upgrade, replacement, and
coordination improvements.
S Valley (I405 - Strander)
Interurban (Scntr - Grady)
S 156 St (W Valley - ECL)
Strander extension $115,000
Design report, PS &E work as development mitigations;
development triggers these work expenditures; work is
primarily approval of developer designed improvments.
57 Ave S $0
Postpone to 1994.
S 134 St $0
Combine with S 133 St work starting in 1994
S 178 St $0
Postpone to start in 1994.
=
TABLE 2 -1
SOIL CHARACTERISTICS
General Soil
Type
Alluvial Soils
Qa
Till Soils
Qt, Q
Outwash Soils
Qo
Bedrock, Rock
Outcroppings
Ti, Tp, Tr, Tt
General
Description
Bearing Capacity
Erosion Hazard
Internal Drainage
Arability
Seismic Stability
Characteristics
related to urban
development
Deep sedimentary soils of
silt, clay and some peat
developed in valley alluvium.
alluvium.
Low
Slight
Poor
Good
Poor
High water table and low
bearing capacity requires
much site preparation prior
to development. High fert-
ility of soil well suited
to agriculture.
Thin soil layer developed
over impermeable glacial
till or bedrock. Relief
generally rolling or hilly.
High
Slight
Fair
Fair
Good
Hardpan occurs a few feet
from soil surface and res-
tricts downward percola-
tion. Soils will support
heavy structures. Slight
erosion, increasing to
moderate on slopes which
exceed 15 %.
Gravelly, dry soils devel-
oped over glacial outwash
deposits. Relief generally
rolling or hilly.
High
Moderate
Good
Poor
Good
Excessively dry soils sub-
ject to erosion if cleared.
Good soils for buildings
with basements. Soils
provide good drainage for
septic tanks and drainfields
but may cause groundwater
pollution.
Thin to no soil layer.
High
Slight
Poor
Poor
Good
Excellent Foundation
stability but subject
to limitation of slope.
Good runoff, slow infil-
tration, few springs.
Based on:
Soil Conservation Service, U.S. Department of Agriculture,
Soil Survey of King County, Washington, 1973,
State of Washington Department of Natural Resources,
Geology and Mineral Resources of King County, Washington, 1971.
2 -10
developmental constraints: 1) low bearing capacity and 2) high water table. These soil types are
naturally suited to light weight buildings or piles.
Till soils are principally found in uplands west of the Duwamish River and north of I-405
(Riverton, Foster and Thorndyke areas). Till soils are hard, blue -gray to gray concrete -like
mixture of clay, silt, sand, and gravel. These soils are excellent for large - building construction
and are considered to have foundation, seismic and slope stability.
The steep hillsides west of I -5 between I-405 and South 115th and east of I -5 between South Ryan
Way and South Wallace Street with slopes between 15 and 70 percent have a high potential for
landslides, and tend to be unstable naturally or become unstable when modified. These limitations
make the hillsides difficult to build on without considerable engineering.
Surface Water Resources
The annexation area is bisected by the Duwamish River flowing north through the area and is
within the Fire District No. 1, Fostoria and Gilliam Creek drainage basins identified by the City
of Tukwila. Separate studies have been prepared for each of these areas and are available from
the City of Tukwila Department of Public Works, Surface Water Utility. The following summary
of each area was prepared from these studies and is intended only to give the reader a general
understanding of the limits and characteristics of each basin.
The Fire District No. 1 Drainage Basin includes that portion of the annexation area which is east
of the Duwamish River and north of an easterly projection of South 144th Street. Approximately
half of the basin's 2900 acres are within the Tukwila city limits. This basin actually consists of
several independent sub -basins which are drained by a combination of natural and man -made
conveyance systems to the Duwamish River and, eventually, the Puget Sound. Because the basin
is bisected by Interstate 5, a significant amount of surface water from the area is drained by State
Highway Department systems. Private drainage systems drain the largely impervious surface area
near Boeing Field.
The portion of the Fostoria Drainage Basin which is within the annexation area is bounded on the
south by South 144th Street, on the west by Military Road, and on the north and east by the
2 -11
Duwamish River. Approximately 1,000 of the basin's 1,600 total acres are within the annexation
area. Topography in the Fostoria basin directs drainage to the northeast and the Duwamish River.
Several unnamed, year round drainage courses flow through the Fostoria basin and the
downstream portions of these features have been routed through a series of man -made ditches and
culverts.
The Gilliam Creek Drainage Basin includes the southern portion of the annexation area bounded
generally by South 160th Street and Highway 518 on the south, Pacific Highway South and
Military Road on the west, South 144th Street on the north and Interstate 5 on the east. Of the
basin's total 1,855 acres, approximately 500 are within the annexation area. Surface water
facilities in the Gilliam Creek basin consists of storm sewers and ditches that drain the area east
of the Sea Tac Airport access freeway, areas north and south of Highways 405 and 518 and area
west of the Green (Duwamish) River. All runoff from this basin is routed to discharge into the
Green River through a 108 -inch diameter pipe with a flap gate.
Wetlands identified in the annexation area occur near the Boeing Access Road, at the Pacific
Highway South and Highway 599 interchange, at the southeastern corner of Allentown and
directly east of the Foster Golf Course on the east side of the Duwamish River. Specific
information on wetlands and other surface water features can be obtained from the City of
Tukwila, Department of Community Development, Sensitive Areas Maps.
Human Environment
This section addresses the human elements of the annexation area including land use, zoning, population,
housing, and employment. Two growth management scenarios are presented in order to project a range
of water system demands and needs. The Tukwila Planning Department has studied the annexed area in
terms of population, housing units, total acreage, vacant land by zoning classification, and sensitive land
areas. The following information is based on their studies.
Land Use Calculations
The following describes the comprehensive land use policy plan, zoning and existing land uses
for the annexed areas. The Comprehensive Land Use Policy Plan for the annexed areas indicates
that the area should develop in the land use patterns shown on Figure 2 -5. In general it would
2 -12
include the Fire District No. 1 as Heavy Industrial for all of the north industrial section; Light
Industrial and Low Density Residential for the Empire Hill area east I -5; Heavy Industrial, Light
Industrial, Commercial and High Density Residential for the Martin Luther King Jr. Way South
area; and Heavy Industrial, Light Industrial and Low Density Residential for the Allentown area.
The Comprehensive Plan also indicates Parks and Open Space along the Duwamish River
shoreline and for the Allentown Park.
The Comprehensive Land Use Policy Plan for the Foster, Riverton and Thorndyke areas generally
shows Low Density Residential with the exception of some Commercial and Medium Density
Residential along Pacific Highway South; Public Facilities Parks and Open Space near Foster
High School on South 144th Street; and Commercial along East Marginal Way South for several
blocks south of South 126th Street.
Existing zoning is shown on Figure 2-6 and described on Table 2 -2. Overall, the Tukwila Zoning
map is consistent with the Tukwila Comprehensive Land Use Policy Plan map.
The land use character of the area is varied ranging from intense industrial to the north to rather
low density single family to the south. Industrial development, including a portion of the Boeing
Field King County International Airport, is in the northern portion of the area. Commercial
development exists along the Highway 99 strip and along East Marginal Way. A mix of
commercial /industrial land use is in the northern end of the Riverton area. Residential use is
scattered in the remaining portions of the study area. The community facilities in the annexation
area include Southgate Park which is undeveloped, South Central Pool, Foster Library, and Fire
District No. 11 fire station. Several major roadways traverse the annexation area. These major
roadways are Interstate 5, State Route 509, State Route 599, State Route 518, State Route
99 /Pacific Highway, East Marginal Way, and Martin Luther King Way South. With the
combined four annexation areas, the City's total acreage rises from 2880 to approximately 5546.
2 -13
—
HDA:3030F2 -5.DWG 6 -17 -91
4
0
CITY OF
SEATTLE
FIGURE .2 -5
COMPREHENSIVE
LAND USE POLICY
TUKWILA
CITY
UMITS
9
Legend
ANNEXATION STUDY
— AREA BOUNDARY
SINGLE FAMILY RESIDENTIAL
MULTI FAMILY RESIDENTIAL
OFFICE
COMMERCIAL
MLIGHT INDUSTRIAL
(
HEAVY INDUSTRIAL
PUBLIC FACILITIES
PARKS & OPEN SPACE
SPECIAL DEVELOPMENT
CONSIDERATIONS
CITY OF SEATTLE
KING COUNTY
8. 120Th 8T.
Y 8.
8. 138Th 8T
KING COUNTY
RENTON
CITY OF SEA -TAC
2000 1000 0 2000
SCALE IN FEET
8. 144TH 8T.
TUKWILA
CITY
OMITS
f SR 818
V
8. 180TH 8T.
City of Tukwila
COMPREHENSIVE WATER PLAN: SUPPLEMENT A - ANNEXATION AREAS
•
W
H
0
A
CITY OF
SEATTLE
TUKWILA
CITY
LIMITS
2000 1000
t9
FIGURE 2 -6
ZONING MAP
Legend
A
ANNEXATION STUDY
AREA BOUNDARY
SINGLE FAMILY RESIDENTIAL
MULTI FAMILY RESIDENTIAL
OFFICE
COMMERCIAL
_ .LIGHT_INDUSTRIAL
HEAVY INDUSTRIAL
PARKS & OPEN SPACE
CITY OF SEATTLE
KING COUNTY
S. 128TH ST
O
1
S. 138TH 8T'
KING COUNTY
RENTON
CITY OF SEA -TAC
0
SCALE IN FEET
2000
TUKWILA
CITY
LIMITS
SR 518
S. 160TH ST.
V
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c
City of Tukwila
COMPREHENSIVE WATER PLAN: SUPPLEMENT A — ANNEXATION AREAS
TABLE 2 -2
LAND USE CATEGORIES
RESIDENTIAL
Low - density residential: These areas are characterized by single - family residential uses; 0 - 5
units per gross acre.
Medium -density residential: These areas are multiple- family in nature and are characterized by
duplexes, triplexes, and fourplexes; 6 - 16 units per gross acre.
High - density residential: These areas are multiple - family in nature and are characterized by
apartment buildings; 17+ units per gross acre.
OFFICE
Office areas are characterized by professional and commercial office uses with certain
complementary retail uses.
COMMERCIAL
Commercial areas include commercial services, retail commercial activities with associated
warehousing, and compatible and complementary uses including offices.
INDUSTRIAL
Light industrial: Industrial areas characterized by distributive and light manufacturing uses,
commercial and office uses.
Heavy industrial: Industrial areas characterized by heavy or bulk manufacturing uses, distributive
and light manufacturing uses, commercial and office uses.
PARKS AND OPEN SPACE
These areas represent public parks, recreation facilities, school playgrounds, and other public
open spaces, including agricultural lands under open space taxation.
PUBLIC FACILITIES
Community facilities include school buildings, churches, government offices, police and fire
stations, and utility facilities.
SPECIAL DEVELOPMENT CONSIDERATIONS
Refers to areas of steep slopes, water surface, and agricultural lands. Along the Green River this
designation refers to that area under shoreline management. This designation does not preclude
development; rather, it depicts areas where urban development must respond sensitively to certain
environmental factors.
2 -16
Population
It is important to note that the population in the combined annexation area is greater than the City
of Tukwila's population prior to the annexation. Since 1970, Tukwila's population has remained
relatively stable, excluding annexation. Beginning in 1985 with the McMicken Heights
annexation, the population of the City has increased greatly. Annexation of Fire District No. 1,
Foster, Thorndyke, Riverton and Cascade View has resulted in an increase in the population from
4,760 to 14,631 persons. These annexations, collectively, are the largest in the City's history in
terms of both population and land area.
In conjunction with the increase in residential population came an increase in employment
population. Strong employment opportunities were reflected in a pre - annexation 1988
employment census of approximately 18,000 employees, which is considerably larger than the
residential population. Estimates of the employment population since the most recent annexation
place that figure near 40,000 employees. It is expected by City planning staff that the residential
population will most likely continue to remain considerably less than the employment population
of the City. Table 2 -3 summarizes existing land use and population data for the overall study area
and individual annexation areas.
TABLE 2 -3
LAND USE AND POPULATION
Fire Dist. Cascade
No. 1 Foster Riverton Thorndyke View Total
Land Area (acres) 1408 196 223 469 370 2666
Population 1308 902 858 2965 2757 8790
Housing Units (total) 663 465 401 1644 1007 4180
Single Family 513 211 282 389 522 1917
Multiple Family 150 254 119 1255 485 2263
Source: City of Tukwila Department of Community Development and Public Works Department.
Land Development Potential
Information on available vacant land was gathered through a drive -by survey conducted by the
Tukwila Planning staff. Table 2-4 shows the amount of vacant land by zoning classification. As
shown in the table, the largest amount of vacant land available in any one zoning classification
2 -17
occurs in land zoned R -1 (One Family Dwelling). Only a limited amount of land is available for
multiple family developments. The R -3 Three and Four Family Dwellings district and the R-4
Low Density Apartment districts contain only 21 and 3 acres of vacant land respectively.
TABLE 2-4
VACANT LAND BY ZONE CLASSIFICATION
Zoning Classification Vacant Acreage
R -A 14.0
R -1 478.0
R -2 44.0
R -3 20.9
R-4 3.0
P -O 6.6
C -1 1.2
C -2 76.2
C -M 20.8
M -1 27.0
M -2 98.0
TOTAL 789.7
Based on analysis of the foregoing data, the following conclusions are made regarding the
development potential of the study area. These conclusions are critical to the development of
realistic scenarios and formulation of an effective Comprehensive Water Plan.
The Comprehensive Land Use Policy Plan is the official guide to the future development of the
annexed area while the Zoning Ordinance provides the means of realizing the goals listed in the
Comprehensive Land Use Plan. The growth scenarios are in conformance of the Comprehensive
Land Use Plan.
Approximately 461 acres of vacant single family zoned land and 14 acres of agricultural zoned
land are available which would permit about 465 additional single family residences.
Furthermore, the 23 acres of vacant multi - family zoned residential land could yield 92 apartment
units. Thus approximately 488 additional dwelling units could be added to the annexed area
through complete build -out of the existing zoning conditions.
2 -18
Approximately 77 acres of land zoned for commercial use is available and 125 acres of land
zoned for industrial use is available. The same average gross floor area to employee ratio as used
for the employee density calculations for the 1990 Water Plan are used to estimate the growth
scenarios below. The average employees per acre, building size factors and gross floor area per
employee are listed in Table 2 -5 below. These density ratios are again used later in this report
for the purpose of calculating water consumption scenarios.
TABLE 2 -5
EMPLOYEE DENSITIES
Employees per Building Factors
Activity Acre (Average) (Average)
Commercial 30 .30
Office 65 .45
Warehousing/Light
Industrial/Wholesale 14.5 .40
Process /Manufacturing 29
Gross Floor Area
per Employee (Average)
435
300
1,200
.40 600
There is limited available vacant land in the C -1 Neighborhood Retail Business, C -2 Local Retail
Business and C -M Industrial Park zones. Conversely, given the current pace of development,
there appears to be an adequate supply of land zoned for M -1 Light Industry and M -2 Heavy
Industry. If land for non - residential development becomes a problem in the future, redevelopment
and intensification of the uses of commercial /retail buildings may offer one solution. At this time
no data has been collected regarding under - utilized land. Under - utilized land may cause a change
in the amount of vacant land listed in the previous table.
Furthermore, it should be noted that some of the available vacant land is within sensitive or
marginal development areas such as steep slopes and wetlands. Given the nature of these lands,
lower than allowable densities may be justified.
2 -19
Growth Management Scenarios
This section presents two growth scenarios for the purpose of evaluating and planning the water systems:
1) existing conditions; and, 2) vacant land buildout. These scenarios are shown on Figures 2 -7 and 2 -8,
respectively and Table 2-6 summarizes each scenario. Redevelopment buildout was not considered at this
time due to lack of available information.
Scenario 1 - Existing Conditions. This scenario is based on the 1989 land use, population,
housing and employment data provided by the Tukwila Planning Department. This scenario is
offered for the purpose of evaluating deficiencies in the existing water system by determining the
adequacy of present facilities and the need for immediate improvements.
Scenario 2 - Vacant Land Buildout. Scenario 2 examines the information provided by the City
and projects what the annexed area would be like if all undeveloped areas were developed in
accordance with the Zoning Ordinance.
TABLE 2-6
PROJECTED DEVELOPMENT SCENARIOS
Scenario 1 Scenario
Existing Vacant Land
Land Use Conditions Build -out
Single Family 1,917 HU 3,830 HU
Multi - Family 2,263 HU 3,625 HU
Office 293,085 GFA 351,000 GFA
Commercial 401,679 GFA 704,700 GFA
Light Industry 1,059,312 GFA 1,392,000 GFA
Heavy Industry 6,625,920 GFA 7,308,000 GFA
Sub -Total Housing Units 4180 HU 7,455 HU
Sub -Total Commercial/
Industrial 8,379,496 GFA 9,755,700 GFA
HU = Housing Unit
GFA = Gross Floor Area
2 -20
1
BOEING FIELD
(Heavy Industrial).
CITY OF
SEATTLE
0
z
FIGURE 2 -7
EXISTING CONDITIONS
TUKWILA
CITY
LIMITS
N9
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— AREA BOUNDARY
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SINGLE FAMILY RESIDENTIAL
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BURLINGTON NORTHERN RAILROAD
(Heavy Industrial)
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KING COUNTY
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COMPREHENSIVE WATER PLAN: SUPPLEMENT A — ANNEXATION AREAS
•
HDA:5030F2 -8.DW0 6 -18 -91
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1� 90 pis
CITY OF
SEATTLE
2000
1000
TUKWILA
CITY
LIMITS
9
FIGURE 2 -8
VACANT - LAND
B UILD O UT
Legend
ANNEXATION STUDY
AREA BOUNDARY
SINGLE FAMILY RESIDENTIAL
MULTI FAMILY RESIDENTIAL
® OFFICE
COMMERCIAL
LIGHT INDUSTRIAL
HEAVY INDUSTRIAL
CITY OF SEATTLE
KING COUNTY
8. 128Th ST.
S.
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KING COUNTY
RENTON
CITY OF SEA -TAC
0
SCALE IN FEET
IHDD'I
2000
TUKWILA
CITY
UMITS
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0
0
1
City of Tukwila
COMPREHENSIVE WATER PLAN: SUPPLEMENT A — ANNEXATION AREAS
CHAPTER 3
EXISTING WATER SYSTEM
CHAPTER 3
EXISTING WATER SYSTEMS
Introduction
There are five water purveyors serving customers within the annexation area: the City of Seattle; King
County Water District No. 125; King County Water District No. 20; the Creston Water Association; and,
the City of Tukwila. This chapter presents general background information and existing system inventory
for each of these water systems. Subsequent chapters address service areas and options for takeover and
exchange of customers within the annexation area. In addition, Appendix A presents a detailed
engineering report which was developed to identify the components of the existing Water District No. 25
system, which was taken over by the City of Tukwila in 1991.
City of Seattle
In addition to providing direct service to customers within the northernmost portion of the Fire District
No. 1 annexation area, the City of Seattle also provides wholesale water service to other purveyor's in
the area. Wholesale water service is achieved by the Cedar River Pipelines, the major transmission
facility from the Cedar River Basin to the City of Seattle distribution system.
Water from the Cedar River is collected in the Chester Morse Lake Reservoir and Dam, which in turn
fills the Lake Youngs Reservoir. From the headworks at Lake Youngs there are three transmission mains.
Two of these transmission lines (Nos. 1 and 3) are interconnected and both are 66 inches in diameter.
Line No. 2 (55 1/2 -inch diameter) operates independently and does not supply the outlying areas of
Seattle. As shown on Figure 3 -1, two additional transmission lines run from the Cedar River Pipelines
west through the City of Tukwila. These are the 48 -inch West Seattle Pipeline along South 112th Street
and Cedar River Pipeline No. 4, a 60 -inch supply line which runs east -west and is south of Highways 518
and 405. These two supply lines are interconnected west of the City by a 36 -inch transmission main along
24th Avenue South.
The hydraulic gradient of these supply lines is directly tied to the elevation of Lake Youngs and they
generally operate at approximately 450', although the actual gradient can vary as much as 30 feet on a
peak day. Purveyor contracts for meters connected to the described Seattle transmission facilities specify
minimum contractual heads ranging from 445' to 455'.
3 -1
EDMONDS
• BOTHEL
- -ate
SNOHOMISH COUNTY
KING COUNTY
DUVALL
TOLT RIVER WATERSHED
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KIRKLAND
1
BELLEVUE
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Puget Sound
r
CEDAR RIVER WATERSHE
• Highland Well Field
► —� Major Supply Lines
• Distribution Reservoirs
1 1 1 1
Scale: 5 miles
HDR
Horton Dennis & Associates, Inc.
Consulting Engineers and Surveyors
Kirkland. Washington • 822 -2525
' Proj No.503/
Drwn)(01.44
IDa t e5i /5/9/
FIGURE 3 -1
CITY OF SEATTLE
REGIONAL SYSTEM
The City of Seattle distribution system, which serves customers in the northernmost portion of the study
area, is part of the 316' pressure zone. The system west of Interstate 5 consists of a 21 -inch steel line
along East Marginal Way South (from the north boundary of the annexation area to S. 112th Street); a
12 -inch ductile iron line along East Marginal Way (from S. 112th St. to the Duwamish River), and; a 12-
inch ductile iron line along Pacific Highway South (from East Marginal Way to the Duwamish River).
The City of Seattle's customers east of Interstate 5 (and within the annexation area) are served by a 12-
inch cast iron line along Martin Luther King Jr. Way S. and South 107th Street, which feeds 8 -inch
distribution lines, as indicated on the Water System Plan Map included with the main body of this report.
King County Water District No. 125
King County Water District No. 125 provides water service to the Foster, Thorndyke and Riverton
portions of the annexation area. Approximately 49 percent of the total District land area is within the
current Tukwila city limits.
Water District No. 125 was formed as such in 1979 and is comprised of three former' districts (Nos. 35,
38 and 43) which had been in operation since the early 1930's. The District operates under Title 57
(Water Districts) of the Revised Code of Washington and has historically retained a board of three
commissioners, a superintendent, and office and field staff.
Water District No. _ 125 receives its entire water supply from the City of Seattle via the Cedar River
system. Metered connections which provide water to the annexation area are as follows:
South 135th Street and Military Road South - 6 -inch
South 115th Street and East Marginal Way South - 8 -inch
South 160th Street and Pacific Highway South - 8 -inch
South 160th Street and 42nd Avenue South - 6 -inch
South 124th Street and 64th Avenue South - 6 -inch
An additional metered connection to the City of Seattle system is located outside of the annexation area,
at South 144th Street and 46th Avenue South.
The District operates under four separate pressure zones based on the gradients of facilities supplying each
area, topography and geographical areas. All four of these zones serve areas within the City of Tukwila.
3 -3
Pressure Zone 1 encompasses that portion of Water District No. 125 which is north of South 136th Street
and extends beyond the District limits to serve one residential development (Seagate) on the north side
of Highway 599.
Elevations in Zone 1 range from 15 to 210 feet. This zone receives its supply from the City of Seattle
318' zone via a metered connection to the Seattle 12 -inch line on East Marginal Way South described
earlier in this chapter. Alternative supply is available through pressure reducing interties from Zone 2.
The Zone 1 distribution system consists of a network of 4, 6, 8 and 10 -inch lines which supply pressure
ranging from 61 to 135 psi. Although there is no storage in Zone 1, flows are sufficient to meet
anticipated fire flow requirements for residential, commercial and public uses.
Pressure Zone 2 occurs in the southern portion of Water District No. 125 and the majority of this zone
is within the annexation area. Zone 2 receives its supply from the City of Seattle's Cedar River Pipeline
No. 4 at an approximate hydraulic gradient of 456'. This is achieved by two metered connections on
South 160th Street. An additional connection to the City of Seattle system occurs atSouth 135th Street
and Military Road South.
The Zone 2 distribution system consists of 10 and 12 -inch lines along major roadways such as 42nd
Avenue South, South 144th Street and Pacific Highway South, and a network of 4, 6 and 8 -inch lines
along other roadways. Pressures in this zone range from 37 psi to more than 150 psi along the west side
of Interstate 5.
Pressure Zone 3 serves the westernmost area of Water District No. 125 and only a small portion of the
annexation area. The area of Zone 3 which within the City is limited to connections along the east side
of Military Road South and those connections which are west of Pacific Highway South and south of
South 146th Street. Pressure Zone 3 receives it's water supply directly from the city of Seattle during
the winter months. To avoid the demand charges associated with high water use during summer months,
however, Zone 3 is supplied by two interties with King County Water District No. 20. This is achieved
by Water District No. 20 purchasing water from the City. of Seattle and pumping it to the 6 million gallon
storage reservoir jointly owned by Water District Nos. 125 and 20. The distribution system serving that
portion of Zone 3 which is within the City is limited to 8 -inch lines along Military Road, South 146th
3 -4
Street and Pacific Highway South. No known deficiencies exist in these facilities.
Pressure Zone 4 serves the area of Water District which is east of Interstate 5. The portion of Zone 4
which is within the current city limits is limited to those customers west of the Burlington Northern
Railroad night -of -way. This includes the rendering works plant along on the east side of the Duwamish
River (south of Foster Point), a few connections on Foster Point, and the area between the old city limits
(generally, 53rd Avenue South) and Interstate 5. The remainder of Zone 4 is in the Campbell Hill area,
east of the railroad right -of -way and outside of the City of Tukwila. This area is addressed in the
SKYWAY CWSP and recommended therein for transfer to the City of Seattle.
Supply to this portion of Zone 4 is through a series of 6 -inch lines from the District's two metered
connections to the Cedar River Pipeline on Beacon Avenue South. Additional supply can be obtained
through an emergency intertie with the City of Tukwila system on 52nd Avenue South just west of
Interurban Avenue South. Pressure Zone 4 has an assigned hydraulic gradient of 478' and elevations
within the area covered by this study range from approximately 15 to 150 feet.
The distribution system for the western portion of Zone 4 consists of a 6 -inch bored crossing of the
railroad tracks, a 6 -inch line through Foster point and 8 -inch crossing of the Duwamish River leading to
a network of 2, 4 and 6 -inch lines. Many of the lines in this area are duplications of City of Tukwila
lines in the same area. Transfer of customers in this area to the City of Tukwila in accordance with the
recommendations of the SKYWAY CWSP would therefore be easily achieved and negotiations for transfer
of facilities are currently underway.
King County Water District No. 20
Water District No. 20 is located west of the City of Tukwila, in the Burien area of King County. The
District serves approximately 8000 connections over a 6.5 square mile area. A small portion of Water
District No. 20 extends into the City of Tukwila to provide water service to the northernmost portion of
the Cascade View annexation area. This area includes medical related, industrial, multi - family and single
family residential connections along Military Road and Highway 99, north of approximately South 131st
Street. Areas to the east and south are served by King County Water District No. 125 and the two
District's not only have interties between them, but also share ownership of a 6 million gallon
underground reservoir.
3 -5
Water supply to Water District No. 20 is purchased from the City of Seattle via their regional water
system. Four pressure zones are maintained and interconnected by PRV's. The District's two highest
pressure zones serve the area of the District which is within the City of Tukwila, as described below.
Existing system facilities within the City are indicated on the Existing System Map provided with the main
body of this report.
The District's 575' hydraulic gradient zone provides water to those connections along Military Road which
are south of approximately South 124th Street. This includes the Riverton General Hospital and other
medical facilities in the vicinity. Under normal operating conditions (non - summer months) the 575' zone
is supplied by the City of Seattle's Burien Pump Station located the intersection of 8th Avenue South and
South 146th Street. Under high demand conditions typical of summer months the District avoids demand
charges by receiving the 575' zone's water supply through the City of Seattle's 456' pressure zone, stores
the Water in a 6 million gallon reservoir (overflow elevation 407.5 feet), then pumps water up to the 575'
zone. Three 3,000 gpm pumps are available to provide flows to the 575' zone during the summer
months.
Storage to the 575' zone is provided by a combination of the City of Seattle's 2 million gallon Beverly
Park elevated storage tank located at the intersection of 4th Avenue South and Southwest 100th Street,
and the District's share of the 6 million gallon reservoir and associated pumping facilities located at 14th
Avenue South and South 120th Street. The Beverly Park storage tank is used for the 575' zones storage
during the lower demand non - summer month and the 6 million gallon reservoir provides storage to the
575' zone during the summer.
Distribution lines serving that portion of the 575' zone which is within Tukwila include an 8 -inch cast iron
line along Military Road and 8 -inch dead end lines serving individual connections in the area. The
remainder of the 575' zone's distribution system consists of a network of pipelines ranging in size from
16- inches to 4- inches. The District's 1986 Comprehensive Water System Plan does not identify any
required improvements to that portion of the 575' zone which is within the City and puts forth target fire
flows of 1500 - 3000 gpm for this area.
The 456 hydraulic gradient serves the remainder of Water District No. 20 connections which are within
the City of Tukwila. This includes three industrial, two single family residential and one motel
connection on the west side of Highway 99, north of South 128th Street.
3-6
Water supply to the 456' zone is provided by the City of Seattle 48 -inch supply line along 24th Avenue
South and Aqua Way. Water can also be provided to this zone through pressure reducing valves from
the 575' zone. Distribution to that portion of the 456' zone which is within the City is provided by an
8 -inch dead end line along a projection of South 128th Street and along Highway 99. No problems have
been identified in this area although the District has noted that pressures are high. Target fire flows for
this area have been identified in the District's Comprehensive Plan as greater than 3000 gpm.
Creston Water Association
The Creston Water Association is a water cooperative of 15 services in the vicinity of 47th Avenue South
and South Ryan Way. The Association purchases its water from the City of Seattle through a 1 1/2 -inch
meter located at Beacon Avenue South and South 107th Street. Water is distributed through a 4 -inch line
along 47th Avenue South. There is no storage in the Creston system.
By agreement, no new connections to the Creston system are allowed and, as services change ownership,
the new owners are required to connect to City of Seattle facilities on 47th Avenue South.
City of Tukwila
The City of Tukwila assumed the assets and water service responsibilities of King County Water District
No. 25 upon dissolution of the District on May 20, 1991. The City now provides direct water service
to the Allentown, Foster Point, Quarry and Empire Hill areas which were previously served by the
District. Pursuant to the takeover process, a separate engineering report was prepared to analyze the
existing water systems in these areas and outline recommended improvements for the Water District No.
25 system. This report is contained in Appendix A to this report and is summarized as follows.
The Empire Hill service area east of Interstate 5 receives its supply through a metered connection to
Seattle's 450' zone near the intersection of South 112th Street and 51st Avenue South. The distribution
system in this area consists of approximately 3000 LF of 6 and 2 -inch dead end lines.
The Allentown Foster Point and Quarry areas are supplied with City of Seattle water through the City of
Tukwila's metered connection to the West Seattle pipeline located near its intersection with South 112th
Street.
3 -7
The distribution system in the Allentown area consists of 2, 4 and 6 -inch lines in most streets. An
additional 10 -inch DI line was constructed by Burlington Northern Railroad along the west edge of its
right of way in 1984.
The Foster Point area is supplied by a 4 -inch line along the Duwamish River from the south end of the
Allentown. Distribution on Foster Point is limited to 2 -inch dead end lines.
The area of Water District No. 25 which is west of the Duwamish River is currently supplied by a 4 -inch
line constructed on a pedestrian bridge across the River at approximately South 120th Street. The
distribution system in this area is limited to 2 and 4 -inch dead end mains.
There is no storage in the Water District No. 25 system.
The City of Tukwila also provides water service to a portion of the annexation area which is east of
Interstate 5 and west of the pre- annexation boundary. Portions of this area are also served by King
County Water District No. 125, as mentioned earlier. Tukwila provides water to this area by 6 and 8-
inch lines extending from its service area to the east.
In addition, the City maintains transmission facilities through the annexation area. These facilities include
a metered connection to the West Seattle Pipeline on South 112th Street and an 18 -inch transmission line
through the Allentown area along South 116th Street and 42nd Avenue South. A 12 -inch line carries
water across the Duwamish on the 42nd Avenue South bridge and continues in a southeasterly direction
down Interurban Avenue South. This line ultimately becomes a source of supply to the northern portion
of Tukwila's water service area. An intertie with Water District No. 125's Zone 2 is located near the
intersection of Interurban Avenue South and 52nd Avenue South.
3 -8
CHAPTER 4
DESIGN CRITERIA AND SERVICE REQUIREMENTS
CHAPTER 4
DESIGN CRITERIA AND SERVICE REQUIREMENTS
Design Criteria
Establishing realistic design criteria is paramount to evaluating the existing water system(s) for adequacy
and determining required improvements. Design criteria includes such elements as water supply
requirements, storage volumes and distribution /transmission main capacity. This criteria is dictated by
State requirements, City of Tukwila policies and developer extension requirements, and standard
engineering practices. In addition, the eastern portion of the annexation area is subject to the minimum
design standards put forth in the SKYWAY Coordinated Water System Plan.
Table 4 -1 summarizes the City's minimum design criteria for future system improvements. A discussion
of the basis for this criteria can be found in the Tukwila 1990 Water Comprehensive Plan (Chapter 4).
Although the criteria listed in Table 4 -1 is consistent with or exceeds the SKYWAY Minimum Design
Standards, a complete copy of those standards is included in Supplement B - Technical Data.
Water Supply and Demand
Table 4 -2 presents the recommended average daily water consumption rates for various types of uses
within the City. This information is a summary of more detailed demand data developed in the 1990
Water Comprehensive Plan and Supplement B - Technical Data.,
In addition to average daily demands, the water system must be able to accommodate fluctuations in flow
rates. Based on historical flow rates, recommended peaking factors have been developed and are
presented in Table 4 -3. Additional data on peaking factors can be found in Supplement B - Technical
Data.
Multiplying the average daily demand of 250 gallons /residential connection /day by the peaking factor of
3.0 results in an average peak day use of 750 /gallons /residential connect /day. This is slightly less than
the State minimum guideline of 800 /gallons /connection /day. It is therefore recommended that
800 /gallons /connection /day be used for estimating peak day water demands.
Although the entire annexation area receives its water supply from the City of Seattle regional water
system, meters from various Seattle transmission mains provide adequate water supply to the entire
annexation area.
4 -1
TABLE 4-1
SUMMARY OF MINIMUM DESIGN CRITERIA
CITY OF TUKWILA COMPREHENSIVE WATER PLAN
Water Distribution Main Size
Residential Areas
o 8" minimum diameter for looped and non - looped lines regardless of whether or not they
supply fire hydrants.
Multi - Residential and Commercial /Industrial Areas
o 10" minimum diameter for looped lines which supply fire hydrants and private fire lines.
o 12" minimum diameter for non - looped lines which supply fire hydrants.
Minimum Storage Requirements
Standby Storage : 48 Hours x average daily flow
Equalization Storage : 0.3 x Standby Storage
Fire Storage : 6000 GPM for 6 hour fire or 2.16 million gallons
Minimum Pressure Requirements
Static Pressure : 140 ± psi - (Elevation in Feet)
2.31
Minimum Residual Pressure: 30 psi
Minimum Required Fire Flow*
Single Family Residential Areas: 1000 Gallons per Minute
Multi- Residential Areas: 2000 Gallons per Minute
Commercial Areas: 2000 Gallons per Minute
Light Industrial Areas: 3000 Gallons per Minute
Heavy Industrial Areas: 3000 Gallons per Minute
* Case by case study recommended for major buildings
Maximum Velocity
10 Feet per Second.
Isolation Valves
Maximum distance between isolating valves in water distribution system equals 800 feet.
Standard Hydrant Spacing
300 feet, center to center.
* See Supplement B for Approved List of Water System Equipment and Materials, and for City of
Tukwila Public Works Water Construction and Development Standards.
TABLE 4 -2
RECOMMENDED AVERAGE DAILY WATER
CONSUMPTION FOR TUKWILA'
(includes irrigation, air conditioners, etc.)
Type of Uses
Residential
Multi- Residential
Retail
Office /Service
Light Industrial/Warehouse
& Distribution
Manufacturing /Heavy
Industrial Processing
Restaurant /Motel
2
Recommended Unit Flow Rate
90 gallons /capita /day
or 250 gallons /unit /day
90 gallons/capita/day
or 140 gallons /unit /day
150 gallons /1000 sq.ft. /day2
80 gallons /1000 sq.ft. /day2
15 gallons /1000 sq.ft./day2
Varies widely (consider on a
case by case basis)
300 gallons /1000 sq.ft. /day2
Refer to Appendix C for list of typical consumption figures for some Tukwila Customers.
Based on gross building floor square footage.
The water system must be able to accommodate fluctuations in flow rates. Based on historical flow rates,
recommended peaking factors are given in Table 4 -3 below. (See Supplement B for back up data).
TABLE 4 -3
DESIGN PEAKING FACTORS
FOR TUKWILA WATER SYSTEM
2
3
4
Average Yearly Flow Rate
Average Peak Month Flow Rate
Average Low Month Flow Rate
Average Peak Day Flow Rate
10 Peak Day Average 15 minute
Peak Flow Rate
15 Minute Peak Flow Rate
1.0'
2.0
0.6
3.02
3.53
6.04
To be used in estimating and projecting yearly water consumption.
To be used in sizing transmission and source requirements.
Basis on which Seattle demand charge is paid.
To be used in sizing the distribution system.
TABLE 4-4
CITY OF TUKWILA ANNEXATION AREAS
PROJECTED AVERAGE DAILY WATER USE
(In 1,000 Gallons per Day)
Scenario 2
Scenario 1 Vacant Land
Land Use 1990 Conditions Build - Out Water Use Factors
Single Family
Residential 479.25 957.00 250 gallons/oonnection/day
Multi Family
Residential 316.75 507.50 140 gallons /unit /day
Commercial 87.50 105.71 0.15 gallons /sq. ft. /day
Office/Service N /A* 28.08 0.08 gallons /sq. ft. /day
Light Industry/
Warehouse N /A* 20.88 0.015 gallons /sq. ft. /day
Process/
Manufacturing 812.50 1,096.20 0.15 gallons /sq. ft. /day
Losses N /A* 271.54 1070" for losses and
unaccounted for water
(leaks, construction etc.)
Total Daily Flow 1,696.00 2,986.91
Total Daily Flow (MGD) 1.70 2.99
Est. Peak Day Demand (MGD) 5.10 8.97
Average Annual Flow (MG) 619,040.00 1,090.22
* Existing water use for commercial and manufacturing uses is based on actual water use figures. These
categories include office and light industry uses respectively. Similarly, losses are included in the water
use data for other categories.
4-4-
In addition to supplying peak consumptive water uses, the City must also be capable of providing adequate
fire protection. As discussed in the 1990 Comprehensive Water Plan, the fire flow guidelines put for the
by the Uniform Fire Code, Appendix IIIA are recommended for use as a guideline for future needs within
the City.
The determination of required fire flows is accomplished on a case by case basis. Factors used to
determine the required fire flow for a building include type of construction materials, total floor area of
the building, exposure to other structures, provision of automatic sprinkler systems, type of occupancy
and other factors. Based on typical single family residences in Tukwila, recommended required fire flow
would be 1000 to 1500 gallons per minute. Multi- residential and commercial /retail fire flows vary to a
present maximum of 6000 GPM.
Future fire flow requirements cannot be exactly determined without precise knowledge of future
construction. However, based on the projected build -out scenario set forth herein, we believe that a fire
flow rate of 8,000 GPM for a duration of eight hours would be a reasonable value to use in determining
ultimate build -out fire flow requirements.
Water System Storage
Water storage is used to regulate pressure within the system, supplement supply sources to meet variations
in demand (and avoid demand charges), meet supply demands in the event of interruption in the systems'
source of supply, and to provide a reserve source of water needed for fire protection.
There are three components of water storage identified as equalization storage, standby storage and fire
reserve storage. These components are defined and discussed in full in the main body of the 1990 Water
Comprehensive Plan.
Required storage for the area has been calculated based on the existing and projected population of the
area expressed in equivalent residential units (ERU's) to compensate for the varying water uses between
single family and multi - family homes. Water consumption records were used to identify Equivalent
Residential Units for commercial and industrial connections within the annexation area. This method
provides a realistic basis for existing water supply and storage requirements, and coupled with the water
use projection figures developed in the main body of this report result in the minimum storage
requirements listed in Table 4 -5.
4 -5
Standby Storage was calculated by simply multiplying the average daily source requirement of 250 gallons
per equivalent residential unit per day by two, to derive the total standby storage required to supply the
system for a 48 hour period. Equalization storage is estimated at approximately 30% of the standby
storage requirement. Fire Storage requirements are based on the fire flow requirements developed in the
main body of this report. Please note if the annexation area were incorporated into the City of Tukwila's
existing water system serving other areas of the City, storage requirements could be reduced by the
storage available or proposed in other areas. In addition, the annexation area currently benefits from
storage in other areas of the purveyors serving the area and this storage continues to benefit those
connections which are within the study area of this Plan. Please refer to Chapter 5 for additional
information regarding recommendations for providing the required storage.
TABLE 4-5
MINIMUM STORAGE REQUIREMENTS
Scenario 1 Scenario
1990 1995 2000 2005 2010 2*
Population 8790 9065 9365 9475 9590 14,000
Equivalent
Residential Units 6784 7820 8017 8468 8528 11,944
Average Daily Flow 1.70 MG 1.96 MG 2.00 MG 2.12 MG 2.13 MG 2.98 MG
(250 gallons /ERU /Day)
Standby Storage 3.40 MG 3.91 MG 4.00 MG 4.24 MG 4.26 MG 5.97 MG
(48 Hour Supply)
Equalization Storage 1.02 MG 1.17 MG 1.20 MG 1.27 MG 1.28 MG 1.79 MG
(30% of Standby Storage)
Fire Storage
Min. Required
Storage **
2.16 MG 2.16 MG 2.94 MG 2.94 MG 3.84 MG 3.84 MG
6000 gpm for 6 Hours 7000 gpm for 7 Hours 8000 gpm for 8 Hours
4.42 MG 5.08 MG 5.20 MG 5.51 MG 5.54 MG 7.76 MG
* Vacant Land Buildout
** Minimum Required Storage = Equalization Storage plus the larger of Standby or Fire Storage)
4-6
CHAPTER 5
RECOMMENDED IMPROVEMENTS
CHAPTER 5
RECOMMENDED SERVICE AREA IMPROVEMENTS
Introduction
This chapter presents alternatives and recommendations for proposed improvements to the water systems
within the annexation area. In that proposed improvements are largely dependent on the City exercising
its options for takeover, the various options for service area expansion discussed in Chapter 2 of this
supplement are again referenced in this section. This chapter also examines the adequacy of existing
systems and summarizes the improvements required to achieve the recommended service areas and insure
adequate service throughout the annexation area. Following these discussions is a detailed listing of
recommended capital improvements. Chapter 6 presents an implementation program for achieving the
recommendations outlined herein.
Service area system evaluations and improvements discussions are divided into geographical areas of the
entire annexation area. The eastern area includes the area which is within the SKYWAY Critical Water
Supply and therefore addressed by the SKYWAY CWSP. The northern portion of the annexation area
includes the area which is north of South 112th Street. The western portion of the annexation area is west
of Interstate 5 and Highway 599 and east of Pacific Highway South.
East Annexation Area
The eastern portion of the annexation area includes that portion of the study area which is west of
Interstate Highway 5 and east of Highway 599. This is the area which is included in the SKYWAY
CWSP. Service to the east annexation area is currently provided by Tukwila (via takeover of King
County Water District No. 25), Seattle, King County Water District No. 125, and the Creston Water
Association.
As discussed in Chapter 2 and illustrated in Figure 2 -2, the SKYWAY CWSP recommends that the City
of Tukwila serve the area west of the Burlington Northern Railroad right -of -way, except for the quarry
area which is west of the Duwamish River and recommended for service by Water District No. 125. The
remainder of the area (east of railroad right -of -way) is recommended for service by the City of Seattle.
The actions required to achieve the service areas recommended by the SKYWAY CWSP are summarized
as follows:
- Takeover of King County Water District No. 25 and replacement of system as detailed
in Appendix A.
5 -1
Interlocal service area agreements and franchises with the City of Seattle and Water
District No. 125 if these entities are to serve portions of Water District No. 25 as
recommended.
Improvements to system and connection of Water District No. 125 customers east of
Interstate 5 and west of railroad right -of -way.
Takeover of King County Water District No. 25 was accomplished in May, 1991 in accordance with the
engineering report contained in Appendix A. Tukwila has therefore assumed service responsibility for
the all customers previously served by King County Water District No. 25, including those which in the
Empire Hill an Quarry areas and recommended for service by others.
Negotiations between the City of Tukwila and the City of Seattle regarding future service to the Empire
Hill area are currently underway. The City of Tukwila may not only retain service to the previous Water
District No. 25 connections in this area, but also assume responsibility for existing City of Seattle
connections which are within the Tukwila city limits. As mentioned in Chapter 2, the Creston Water
Association provides water to approximately 15 connections on Empire Hill which are intended for
transfer to the City of Seattle. This will also be considered in the negotiation between the two cities.
The Quarry area, which is identified in the SKYWAY CWSP as being served in the future by Water
District No. 125, will remain the responsibility of the City of Tukwila at least until lines in the area are
replaced. An intertie with Water District No. 125, however, would greatly improve the reliability of
service in this area and has been included in cost estimates for replacing the Water District No. 25
system.
As documented in Appendix A, replacement of the entire Water District No. 25 system is required,
including approximately 48,000 LF of pipe at an estimated cost of more than $2.5 million. If the City
of Tukwila were to takeover City of Seattle services within the area, additional improvements would be
required to provide adequate service to the area and intertie the two systems. These additional
improvements have not been included in this Plan and should be identified as part of the negotiating of
future service areas. Provision of required storage is discussed later in this Chapter.
Negotiations for transfer of Water District No. 125 customers east of Interstate 5 and west of the
Duwamish River area also underway. Although the City of Tukwila maintains water lines within the
vicinity of the Water District No. 125 which is to be taken over by Tukwila, upgrading of some facilities
in this area will be required to extend adequate service and fire flows to all customers. The City of
5 -2
5 -3
of service to be provided by each party should be identified and minimum design criteria established for
future projects within the City limits. Any future water line development by the Districts which occurs
within the city limits should be submitted to the City of Tukwila for review and approval.
The City ,nay, however, wish to take over service to the western annexation area at some future date.
Because the majority of the remaining portion of Water District No. 125 and a portion of Water District
are within the recently incorporated City of Sea Tac, these area are subject to the potential for takeover
by Sea Tac. If the City of Sea Tac were to exercise its authority to takeover portions of these Districts
which are within their city limits, the City of Tukwila would likely do the same. At that point some
pipeline upgrades would be recommended for the area. No significant deficiencies are know and these
upgrades would likely be limited to routine replacement of older and /or leaking facilities. Consideration
should also be given to the lack of storage in the Water District No. 125 system. The majority of the
Water District No. 125 area which is within the City limits is currently without storage. Storage
requirements for the entire annexation area are presented in Figure 5 -1 and discussed below.
Water System Storage
As discussed in Chapter 4, the total required storage for the entire annexation area is estimated at 4.42
million gallons currently, increasing to an estimated 5.52 million gallons at the 2010. These estimated
storage requirements are indicated on Figure 5 -1 and represent the minimum required storage for the area
based on provision of equalization storage plus the larger of standby or fire storage. In that the City
currently has approximately 2 million gallons of storage available, consideration of how the minimum
storage capacity is going to be provided after takeover of facilities within the annexation area must be
given prior to the takeover.
With the exception of the Empire Hill area, the eastern portion of the annexation area is or will be
connected to the City's main distribution system and consequently, the existing 2 million gallon North Hill
reservoir. Although this storage is not adequate to satisfy the entire needs of the City, as discussed in
the main body of this report, it will provide a direct benefit to these areas in the event of a fire or loss
of supply. The size of the tank in relation to the entire City of Tukwila service area will limit its
effectiveness in providing equalization storage. Equalization storage, however, can be provided in the
City of Seattle's regional water system although this results in demand charges to compensate for high
water use during the summer months. These areas will benefit from the additional storage facility
recommended in the amain body of this report and should be considered in the sizing of that storage
reservoir.
5-4
The Empire Hill area of the City, if served in the future by the City of Tukwila, will require a relatively
small amount of storage because of the residential nature and limited size of the area. The SKYWAY
CWSP recommends a joint use storage facility on the Skyway Hill to benefit all purveyors in the area.
It is recommended that the City of Tukwila participate a proportionate share of this facility if water
service is to be provided to Empire Hill.
The northern portion of the annexation area includes Boeing Field and industrial uses along East Marginal
Way. These Facilities combine to make up approximately 50% of the total required storage for the
annexation area. Although this area of the City could be connected to the City of Tukwila's water system
facilities in the Allentown area, the storage requirements for this area exceed the size of the existing North
Hill reservoir. It is therefor recommended that the City consider options for provision of storage in this
area during its negotiations for future service to the area. In that the area currently relies on the City of
Seattle system for storage and would continue to be a part of the Seattle regional system even if the City
of Tukwila provides service, continued provision of storage in the City of Seattle system via an intertie
may be feasible.
Although the North Hill reservoir will significantly reduce the City's pre - annexation storage deficit,
another reservoir is required to provide adequate storage volumes for existing development conditions
throughout the City. As discussed in the 1990 Water Comprehensive Plan, a new storage facility with
an estimated capacity of 5 million gallons is recommended. Because the entire City operates on one
pressure zone, increasing the capacity of this facility could allow the City to serve additional area from
the proposed West Hill reservoir and provide storage to at least a portion of the annexation area from the
North Hill reservoir. Consideration of the potential for takeover of the entire annexation area should be
included in the final sizing calculations of the recommended reservoir. As an alternate to provision of
storage to the entire annexation area, the City should consider construction of a storage facility within,
or closer to the annexation area.
5 -5
TOTAL CITY POPULATION
16000
14000
12000
MINIMUM REQUIRED
STORAGE (TOTAL CITY)
POPULATION (PREVIOUS
CITY LIMITS)
MINIMUM REQUIRED 4000
STORAGE (ANNEXATION
AREA ONLY)
1 0
o
co cn ° c
°' cn o 0 0
N N N
11ME IN YEARS
CITY OF TUKWILA
RECOMMENDED WATER
Horton Dennis & Associates, Inc. STORAGE IMPROVEMENTS
Water Lines
The City of Tukwila water line size requirements are in many cases larger than existing facilities within
the annexation area. As new facilities are constructed by other purveyors within the City limits, they
should be to the requirements put forth by the City in anticipation of being part of the Tukwila system
at some future date.
Existing facilities which are in need of replacement in the near future are as listed in Table 5 -1. These
improvements have been identified as required in order to provide reasonable water service and fire flows
to all customers being served directly by the City of Tukwila and do not include improvements which may
be desirable within areas to be served by others. In addition to the improvements listed in Table 5 -1,
complete replacement of the Water District No. 25 system is recommended and is therefore\addressed in
Appendix A.
TABLE 5 -1
PROPOSED WATER IMPROVEMENTS
FOR ANNEXED AREAS OF TUKWILA
WITHIN WATER DISTRICT NO. 125
NO.
SIZE
(IN.)
FROM
ALONG
TO
LENGTH
(LF)
COST /LF
ESTIMATED
COST
59S
12
Foster Point Supply Main
2500
80.00
200,000.00
60S
12
S. 160th St.
42nd Ave. S.
S. 158th St.
660
80.00
52,800.00
61S
8
S. 139th St.
51st Ave. S.
S. 140th St.
550
65.00
35,750.00
62S
8
52nd Ave. S.
S. 136th St.
and 51st Ave. S.
S. 137th St.
1000
65.00
65,000.00
63S
8
53rd Ave. S.
• S. 142nd St.
and 52nd Ave. S.
Dead Ends
1000
65.00
65,000.00
TOTAL
415,550.00
WITHIN WATER DISTRICT NO. 25
- Please refer to the Water District No. 25 Supplemental Engineering Study, March 1991 included in Appendix A to this
document.
WITHIN THE CITY OF SEATTLE SERVICE AREA
- The City of Seattle in 1993 had planned to install a new 12" DI distribution line along E. Marginal Way S. from
Michigan Street to S. 112th Street and convert the existing 21" line to a transmission line. The project has been deferred
due to reprioritization of budgeted projects. If the City of Tukwila elects to takeover service to this area and subsequently,
installs the required 12,000 LF of 12 -inch Ductile iron pipe, the estimated project cost is $960,000.
� -
CHAPTER 6
IMPLEMENTATION
This Chapter presents the required actions for implementation of the service areas and system
improvements discussed and recommended in Chapter 5. Financial considerations, service area and
franchise agreements, and legal considerations are summarized for the annexation area only. Additional
information on the City's financial considerations and developers extension policies is included in the 1990
Water Comprehensive Plan.
Service Areas and Interlocal Agreements
Achieving the service areas recommended in Chapter 4 of this supplement requires coordination of actions
summarized below.
Takeover of King County Water District No. 25 has been accomplished, but negotiations are underway
with the City of Seattle regarding future service to that portion of the City of Tukwila which is east of
I -5 in the Empire Hill area. If the City of Tukwila assumes service to connections in this area, an
amendment to the SKYWAY Coordinated Water System Plan is required.
Takeover of Water District No. 125 Customers east of Interstate 5 (in the vicinity of 51st Avenue South)
requires an interlocal agreement between the District and Tukwila for the transfer of facilities to the City;
reconnection of Water District No. 125 customers to Tukwila lines, and; replacement of undersized lines
as identified in Chapter 4.
The City of Tukwila is currently discussing takeover of City of Seattle connections in the northern portion
of the annexation area in the vicinity of Boeing Field. An interlocal agreement will be required to identify
the terms of transfer of services in this area. Additionally, the City of Seattle, should apply for a
franchise to operate water line facilities within the Tukwila city limits.
Other purveyors operating utilities within the City should also be required to obtain franchises which
outline the conditions by which they are allowed to operate facilities within the City limits. In addition,
the City may wish to enter into interlocal agreements with each of these purveyors which identify the
specific areas they will serve and requirements for City review of projects installed which may at a future
date become part of the City system.
6 -1
Financial Considerations
Various options for financing capital improvements projects are presented in the 1990 Water
Comprehensive Plan. Consideration of financing by rates is addressed separately in this document because
it applies to the annexation area specifically. The philosophy behind this type of financing is that the
existing City of Tukwila rates are based on construction of facilities within the previous city limits which
provide little or no benefit to potential customers within the annexation area. As detailed in Appendix
A, in taking over Water District No. 25, the city elected to apply an amount equal to the difference
between Water District No. 25 rates and City of Tukwila rates to construction of facilities within the
Water District No. 25 area. This method of financing should be considered for other areas within the
current city limits which were previously served by others.
Table 6 -1 presents a rate comparison chart of the various water purveyors providing service within the
annexation area. By applying the current City of Seattle rates for water service to the estimated amount
of water used in 1989 in the northern annexation area, along East Marginal Way in the vicinity of Boeing
Field, a area, we calculate an estimated annual revenue to the City of Seattle of approximately $267,090.
Provision of the same service at the current City of Tukwila rates would generate approximately $538,950
over the course of one year, resulting in a difference of $271,860. This amount could be applied to the
approximate $960,000 in pipeline replacements identified for this area in Chapter 5. Although this
provides an attractive method of financing of the improvements in this area, dedication of the entire
difference in rates may not be equitable. This is because the City of Seattle's cost of operation is lessened
by the large area it serves and is not subject to the same rates and charges that a water purveyor such as
the City of Tukwila is. Consideration should therefore be given to determining an equitable percentage
of the rate difference to be dedicated to system improvements.
Table 6 -1 also presents the rates of King County Water District Nos. 125 and 20. As the City considers
specific areas for takeover in the future, similar comparisons in rates can be made and these amounts
applied to the required improvements in each area. For Water District No. 125, approximately
$2.00 /single family residence /per month can be anticipated in rate differential. Water District No. 20
however, has current rates higher than the City of Tukwila's for residential users and most classifications
of commercial accounts.
6 -2
TABLE 6-1
WATER RATE COMPARISON
City of Tukwila
Water District 125
Water District 20
City of Seattle
(Outside City)
Summer
Winter
Summer
Winter
Summer
Winter
Summer
Winter
Single Family Residential
Base Rate plus 1000 cubic feet
$15.00
$14.00
$12.50
$11.00
$17.75
$15.75
$14.26
$13.60
Single Family Residential Water Rate
Per 100 cubic feet
$1.10
$1.00
$0.75
$ .060
$1.021*
$1.531**
$1.021
Multi- family Residential
. 10 units plus 5700 cubic feet
$102.70
$97.00
$84.75
$72.60
$98.35
$86.95
$61.87
$37.17
Multi Family Water Rate
per 100 cubic feet
$1.10
$1.00
$0.75
$0.60
$0.70
$0.50
$0.873
$0.582
Commercial/Industrial
•
3/4" Meter plus 5000 cubic feet
$80.00
$74.00
$49.70
$39.70
$46.25
$31.70
5/8" Meter plus 5000 cubic feet
$42.50
$35.00
$49.70
$39.70
1" Meter plus 5000 cubic feet
$85.00
$79.00
$44.50
$37.00
$53.10
$43.10
$47.65
$33.10
1 1/2" Meter plus 5000 cubic feet
$90.50
$84.50
$48.00
$40.50
$66.70
$56.70
$48.95
$34.40
2" Meter plus 5000 cubic feet
$96.00
$90.00
$55.00
$47.50
$87.10
$77.10
$51.25
$36.70
3" Metre plus 5000 cubic feet
$118.50
$112.50
$69.00
$61.50
$124.50
$114.5
$57.55
$43.00
4" Meter plus 5000 cubic feet
$134.50
$128.50
$97.00
$89.50
$178.90
$168.90
$69.35
$54.80
6" Meter plus 5000 cubic feet
$186.50
$180.50
$153.00
$145.50
$314.90
$304.90
$88.65
$74.10
8" Meter plus 5000 cubic feet
$247.50
$241.50
$208
$200.50
$445.90
$435.90
$122.65
$108.10
Commercial Water Rate
per 100 cubit feet
$1.43
$1.31
$0.75
$0.60
$0.70
$0.50
$0.873
$0.582
* Rate Applies to first 500 cubic feet only.
** Rate applies to each 100 cubic feet over 500 cubic feet.
APPENDIX A
CITY OF TUKWILA
WATER DISTRICT NO. 25
SUPPLEMENTAL ENGINEERING STUDY
June 1990
Revised March, 1991
Prepared By:
Horton Dennis & Associates, Inc.
Consulting Engineers
Kirkland, Washington
CITY OF TUKWILA
WATER DISTRICT NO. 25
SUPPLEMENTAL ENGINEERING STUDY
June 1990
Revised March, 1991
Piepared By:
HORTON DENNIS & ASSOCIATES, INC.
Consulting Engineers
Kirkland, Washington
CITY OF TUKWILA
WATER DISTRICT NO. 25
SUPPLEMENTAL ENGINEERING STUDY
The technical material and data contained in this report were prepared under the supervision and direction
of the undersigned, whose seal as a professional engineer licensed to practice as such in the State of
Washington is affixed below.
/7/off-
Martin L. Penhallegon
President
Horton Dennis and Associates, Inc.
TABLE OF CONTENTS
PAGE
I. INTRODUCTION 1,
H. BASIC PLANNING DATA 4
Land Use Zoning 4
Population 4
Water Consumption 5
III. EXISTING SYSTEM 6
Water Supply 6
Facilities 6
IV. SYSTEM DEFICIENCIES 7
V. NEEDED IMPROVEMENTS AND COST 11
VI. IMPLEMENTATION AND FINANCING 13
Dissolution and Assumption 13
Financing 14
VII. FINANCING ALTERNATIVES 18
Recommended Financing Program 18
Financing Alternatives 20
Other Funding Options 24
LIST OF TABLES
TABLE 1 - POPULATION PROJECTIONS 5
TABLE 2 - PROJECTED ANNUAL WATER DEMAND 5
TABLE 3 - PIPE INVENTORY 9
TABLE 4 - ESTIMATED RATE INCREASE REVENUES 18
TABLE 5 - RECOMMENDED FINANCING ALTERNATIVE ANNUAL COSTS 19
TABLE 6 - FINANCING ALTERNATIVE 1 SUMMARY 21
TABLE 7 - FINANCING ALTERNATIVE 2 SUMMARY 22
LIST OF MAPS
MAP 1 VICINITY - BOUNDARY 2
MAP 2 SKYWAY CWSP RECOMMENDED SERVICE AREAS 3
EXISTING SYSTEM MAP MAP
POCKET
FUTURE SYSTEM MAP MAP
POCKET
CITY OF TUKWILA
WATER DISTRICT NO. 25
SUPPLEMENTAL ENGINEERING STUDY
INTROD UCT7ON
This study is intended to supplement the City of Tukwila Water Comprehensive Plan and provide
detailed information regarding the provision of water service to Water District No. 25, which is
in the Allentown area of the City. This area was annexed by the City in 1989 as part of the Fire
District No. 1 Annexation and, as shown on Map 1, the legal boundaries of Water District No.
25 are now entirely within the current Tukwila City Limits.
Upon annexation of territory which includes existing utility districts, a city may elect either to:
1) enter into an agreement with the utility district to continue service to an area; or 2) take over
the district's service responsibilities for the area. The Final Environmental Impact Statement
prepared for the Fire District No. 1 Annexation recommends that the City take over service
responsibilities from King County Water District No. 25 and the District has indicated a desire
to be relieved of their service responsibilities.
The SKYWAY CWSP also recommends dissolution of Water District No. 25, with future water
service to the area being divided between three separate purveyors according to the following
geographical areas (as shown on Map 2):
The main portion of the District, consisting of Allentown and Foster Point, will be served
by the City of Tukwila. This includes the portion of Water District No. 25 west of the
Burlington Northern Railroad tracks and east of the Duwamish River. There are
approximately 382 connections in this area.
The Empire Hill portion of the District is east of Interstate 5 and is to be served by the
City of Seattle. This consists of the 34 residential connections along the northeastern City
of Tukwila boundaries in the vicinity of South 114th Street and 51st Avenue South.
The Quarry area of the District is west of the Duwamish River and east of State Route
181. The SKYWAY CWSP recommends that the 81 connections in this area be served
by Water District No. 125. Additional options for service to this area are discussed later
in this report.
1
WIN MI
ISM
TU. WILA
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1
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8E1ATTLEI
SO. 120th ST.
▪ X],\1. rJJNTY
•
LEGEND
— — — — City Limit
m•••••"' WD 26 Legal Boundary
TUKWILA
CITY LI
MAP 1
VICINITY - BOUNDARY
MAP
NON
Horton Dennis & Associates, Inc.
end_ ..
1•1111 /40. *SIT 1.1p -fl0
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el)
II. BASIC PLANMNG DATA
This supplemental study addresses the area within the legal boundaries of King County Water
District No. 25, which is shown on Map 1. The area is within the Duwamish River Basin and
is generally bounded by East Marginal Way and the Duwamish River on the west and south,
Interstate Highway 5 and the Seattle City Limits on the east, and South 112th Street on the north.
Elevations in the area range from 15 feet above sea level in the main and western portion of the
District to nearly 350 feet in the area east of Interstate Highway 5.
Land Use and Zoning
Land use in the study area is primarily single family residential. There are a few commercial and
industrial uses along the Burlington Northern Railroad tracks and at the intersection of 44th Place
South and 46th Avenue South (Union Tank Works). Zoning in the area is consistent with existing
land use patterns, with the majority of the area zoned low density residential (R- 1 -7.2).
Manufacturing zoning (M -2) is limited to the area just west of the railroad tracks, the Union Tank
Works site and the property north and east of the intersection of East Marginal Way and South
115th Street. Commercial and multi - family zoning occur along South 116th Street. Detailed land
use and zoning information can be obtained from the Tukwila Department of Community
Development.
Population
The District currently serves approximately 497 connections. All but approximately 12 of these
are single family residential accounts. The majority of the District is within U.S. Census Tract
No. 263 which, according to the Puget Sound Council of Governments, has an average household
size of 2.08 persons per household. Multiplying the estimated 485 residential connections by this
average household size of 2.08 results in an estimated District population of 1009 people.
Census Tract 263 is included in the Puget Sound Council of Governments Forecast Analysis Zone
3820 (Riverton) for population forecasting purposes. Although the District constitutes only a
small portion of the total Forecast Analysis Zone, the projected growth rates for the zone have
been applied to the estimated current population to determine future population of the area.
4
TABLE 1
POPULA77ON PROJEC77ONS
Year Population
1990 1,009
2000 1,075
2020 1,127
Water Consumption
The recommended average daily water consumption developed for the 1990 City of Tukwila
Comprehensive Water System Plan (Table 4 -1), indicates that an average of 250 gallons per
residential connection per day should be used for water consumption planning. Review of Water
District No. 25's hisio1 water consumption data obtained from the City of Seattle water sales
data (1983 through 1987) indicate that consumption within the District coincides with that
average. Projected residential equivalents (R.E.'s) and associated annual 'water demands are
shown in Table 2 and are presented for each area of District. These figures are based on existing
zoning and Puget Sound Council of Government population projections. Please note that although
projected demand figures are important in assessing the future water supply needs, pipe sizing
within the City of Tukwila is generally dictated by required fire flows.
TABLE 2
PROJECTED ANNUAL WATER DEMAND
1990 2000 2020
Est. Annual Est. Annual Est. Annual
R.E.'s Demand R.E's Demand R.E.'s Demand
Allentown, Foster Point 382 34.86 MG 407 37.14 MG 427 38.96 MG
Empire Hill /Eastern Area 34 3.10 MG 36 3.29 MG 38 3.47 MG
Quarry/Western Area 81 7.39 MG 86 7.85 MG 90 8.21 MG
TOTAL 497 45.35 MG 529 48.28 MG 555 50.64 MG
5
III. EXISTING SYSTEM
Water Supply
All of Water District No. 25 is supplied with water, directly and indirectly, from the City of
Seattle regional water system via the Cedar River Pipelines and 48 -inch West Seattle Supply Line.
The main and western portions of the District receive water supply through an intertie to the City
of Tukwila's 18 -inch transmission main through the Allentown area. The unmetered intertie is
at the intersection of South 116th Street and 44th Avenue South and was constructed in 1989.
The Tukwila transmission main is supplied by a metered connection to the City of Seattle's 48-
inch West Seattle Supply Line near South 112th Street and 40th Avenue South. Before
construction of the Tukwila - Water District No. 25 connection, the District purchased its water
for the main portion of the District directly from the City of Seattle through a metered connection
to the West Seattle Pipeline at East Marginal Way and South 112th Street. This connection was
abandoned as a result of reconstruction of the Interurban Bridge on East Marginal Way.
The source of water for the area east of I -5 is a metered 6 -inch connection to the City of Seattle's
Cedar River Pipelines at South 112th Street and Beacon Avenue South.
The District's distribution system, source meters and interties are shown on the Existing System
Map located in the back pocket of this document.
Facilities
The District facilities consist entirely of distribution system pipelines and meters. There are no
pump stations or storage reservoirs in the existing system. The distribution system consists of
2 -inch and 4 -inch mains in most streets. The original supply pipe along South 115th Street and
42nd Avenue South is 6 inches in diameter.
Foster Point is supplied by a 4 -inch main along the Duwamish River from the south end of the
Allentown area. The area West of the River is served by a 4 -inch main constructed on a foot
bridge across the river at approximately South 120th Street. Distribution within the area east of
I -5 is provided by a dead end 6 -inch and 2 -inch line. Detailed information on pipe sizes and
materials can be found on the Existing Water System Map and Table 3 (pages 9 -10).
6
Most of the pipes were installed in the 1920's and are 6 -inch and 4 -inch lead pack joint cast iron
lines. The 2 -inch and smaller pipes are galvanized steel. There are also small amounts of newer
6 -inch and 4 -inch cast iron, 6 -inch asbestos cement, and small polyvinyl chloride. The 10 -inch
BNRR line is ductile iron. The condition of the pipes is variable depending on the soil condition
in which they are placed. Generally the pipes west of the river are in good condition and the
pipes east of the river are in poor condition.
In 1984 the Burlington Northern Railroad (BNRR) constructed a 10 -inch ductile iron water main
parallel to the railroad tracks through its intermodel terminal in Water District 25. The main
provides fire suppression capability for the terminal and receives its water supply from the City
of Tukwila. This line is considered as part of the ultimate distribution system for the area and,
therefore, the City should obtain easements for the facility. The required connection to the
Tukwila water system are shown on the system maps.
IV. SYSTEM DEFICIENCIES
Except for the 10 -inch BNRR main, all of the pipes in Water District 25 are of insufficient size
and inadequate materials to meet the City of Tukwila's minimum design standards. Although
the District pressure of 100. psi somewhat compensates for insufficient pipe sizes, the existing 6-
inch source limits the fire flow anywhere in the District. Flows of approximately 1000 gpm are
available immediately adjacent to the source in the main portion of the District, but drop off
quickly as the distance from the source increases. On the streets with 4 -inch lines, the maximum
flow available is 350 gpm. The 2 -inch mains and standpipes are limited to less than 100 gpm.
Corrosive soils in the area contribute to deteriorating and leaking lines, especially in the area east
of the Duwamish River.
Upgrading the existing system to Tukwila standards will require replacement of the entire system
and installation of fire hydrants, except for the existing 10 -inch BNRR line. The upgraded system
should then be intertied to the BNRR line and the City's 18 -inch transmission line which traverses
the area. In addition, it is anticipated that some meters will need to be replaced. Since Tukwila
operates at pressures about 60 psi higher than Water District 25 individual pressure reducing
7
valves will probably be needed at each meter.
The SKYWAY CWSP indicates the area west of the river is to be served by Water District 125
and that the area east of the railroad tracks will be served by the City of Seattle. Provisions for
connection to these systems will need to be made.
Future annexations of Water District No. 125 territory into the City of Tukwila may make
provision of water service by Water District 125 in the Water District No. 25 area impractical.
The Water District 125 area adjacent to the Water District 25 area west of the River may
ultimately be part of the Tukwila distribution system. If that is to occur, the transfer of these
services would only be temporary and may be unnecessary.
As alternatives, the City could purchase water from Water District 125 until it takes over W.D.
125's service area, or, the City could install its own supply mains to the area. City supply mains
to the area would require a river crossing on existing structures (foot bridge or Interurban Bridge)
and would be a dead end unless a long extension to the south along Interurban Avenue was
constructed.
As an alternative to transferring the services east of Interstate 5 to the City of Seattle, Tukwila
could maintain service in the area. This is not consistent with The SKYWAY CWSP Plan and
would require an amendment to that Plan. The principle problem with this alternative is the
requirement to provide storage for the area. It may be necessary to construct a costly supply line
to the area across the railroad and I -5 to provide access to storage in Tukwila's West Hill Tank.
All details regarding the transfer of service areas will need to be negotiated between the receiving
utility and the City. The.requirements for pipe replacement, time schedules for the transfer and
financial arrangement should be addressed during these negotiations.
8
• - - - -
NOTES:
1990 UNIT PRICE
1 SUPPLY CONNECTION TO BN PIPELINE . . .
2 EXISTING PRV STATION TO BE REPLACED BY CONNECTION
3 4 INCH DI ON DUWAMISH RIVER FOOT BRIDGE TO BE ABANDONED
4 EXISTING BN HYDRANT LINE
5 EXISTING WATER DISTRICT NO. 125 PIPELINE
6 PURCHASE COST OF WATER DISTRICT 125 FOSTER POINT BRIDGE PIPELINE
7 ADD HYDRANTS AND SERVICES TO EXISTING 18" TRANSMISSION•MAIN
8"= 360.00
10" = 370.00
12 "= 380.00
TABLE 3
PIPE INVENTORY
EXISTING WATER
DISTRICT 25
SYSTEM
TUKWILA
ZONING
ULTIMATE
SIZE
ULTIMATE
REPLACEMENT
PHASE 1
PHASE 2 ,
PIPE
NO.
LENGTH SIZE(IN.)
(FEET) MATERIAL
SIZE
(INCHES
COST
SIZE
(INCHES) COST
SIZE UNIT
(INCHES) PRICE
ALONG
1 FROM
ITO
(INCHES)
206 130th PL.S.
S. 129th
56th Ave. S.
1250
4 CI
12 -
12
100000
0
12
100000
207 56th Ave. St.
Interurban Ave.
800 ' east of Interurban
800
8 DI (5)
8
100000 (6)
100000 (6)
210 S. 116th S.
43rd Pl. S.
BN pipeline
430
10 DI (1)
10
10
30100
10
30100
0
211 Tukwila - WD 25 intertie
40
PRV (2)
8
8
2400
0
8
2400
213 43 PI. & 44th Ave. S.
S. 116th S.
S. 118th St
1070
6 CI
8
8
64200
0
8
64200
214 S. 116th St.
43rd Pl. S.
42nd Ave. S.
150
6 CI
12
12
12000
0
12
12000
215 S. 115th St.
42nd Ave. S.
40th Ave. S.
930
6 AC
12
12
74400
0
12
74400
216 S. 1 15th St.
40th Ave. S.
E. Marginal Way
1050
6 AC
12
12
84000
0
12
84000
217 40th Ave. S. & S. 113th St. S. 115th St.
End
1060
2 ST
8
8
63600
8
63600
0
0
218 42nd Ave. S.
S 116th St.
S. 119th St. (easement)
1120
6 CI
8
18(7)
30000
18(7)
30000
0
219 S. 119th St. (easement)
42nd Ave. S.
41st Ave. S. (easement)
520
4 DI (3)
8
0
0
0
220 41st Ave. S. (easement)
S. 119th Ave. S.(easement)
End
170
4 CI
8
8
10200
8
10200
0
221 S. 119th St.
41st Ave. S. (easement)
40th Ave. S.
180
4 CI
8
8
10800
8
10800
0
222 40th Ave. S. (easement)
S. 119th St.
Southerly to end
600
2 ST
8
8
36000
8
36000
0
223 40th Ave. S.
S. 119th St.
S117th St.
630
4 CI
8
8
37800
8
37800
0
224 S. 117th Ave. S.
40th Ave. S.
39th Ave. S.
340
4 CI
8
8
20400
8
20400
0
225 S 117th St. (easement)
39th Ave. S.
End
340
2 ST
8
8
20400
8
20400
0
226 39th Ave. S.& S. 116th St.
S. 117th St.
38th Ave. S.
600
2 ST
8
8
36000
8
36000
0
227 39th Ave. S.
S. 116th St.
End
330
2 ST
8
8
19800
8
19800
0
228 42nd Ave. S.
S. 119th St. (easement)
S. 122nd St.
980
6 CI
8
18(7)
30000
18(7)
30000
0
229 42nd Ave. S.
S. 122th St.
S. 124th St.
700
4 CI
8
8
42000
8
42000
0
230 S. 122St.
42nd Ave. S
43rd Ave. S
300
4 CI
8
8
18000
8
18000
0
231 43rd Ave. S.
S. 122nd St.
S. 124th St.
231
2 ST
18(7)
18(7)
4000
18(7)
4000
0
232 S. 124th St.
42nd Ave. S.
43rd Ave. S.
250
4 CI
12
12
20000
12
20000
0
233 S. 122nd St.
43rd Ave. S.
44th Ave. S.
170
4 CI
8
8
10200
8
10200
0
234 44th Ave. S.
S. 122nd St.
S. 118th St.
1400
2 ST
8
8
84000
8
84000
0
235 S. 122nd St.
44th Ave. S.
44th Ave. S.
100
4 CI
8
8
6000
8
6000
0
236 44th Ave. S.
S. 122nd St.
S. 124th St.
700
2 ST
8
8
42000
8
42000
0
237 45th Ave. S.
S. 122nd St.
S. 124th St.
700
2 ST
8
8
42000
8
42000
0
238 46th Ave. S.
S. 122nd St.
S. 124th St.
700
2 ST
8
8
42000
8
42000
0
239 47th Ave. S.
S. 122nd St.
S. 124th St.
700
2 ST
8
8
42000
8
42000
0
242 51th PI. S.
S. 122th St.
S. 124th St.
1060
2 ST
10
10
374,200
10
374,200
SO
243 S. 122th St.
44th Ave. S.
45th Ave. S.
230
4 CI
10
10
316,100
10
316,100
SO
240 48th Ave. S.
S. 122nd St.
S. 124th St.
700
2 ST
8
8
42000
8
42000
0
241 49th Ave. S.
S. 122nd St.
S. 124th St.
700
4 CI
8
8
42000
8
42000
0
NOTES:
1990 UNIT PRICE
1 SUPPLY CONNECTION TO BN PIPELINE . . .
2 EXISTING PRV STATION TO BE REPLACED BY CONNECTION
3 4 INCH DI ON DUWAMISH RIVER FOOT BRIDGE TO BE ABANDONED
4 EXISTING BN HYDRANT LINE
5 EXISTING WATER DISTRICT NO. 125 PIPELINE
6 PURCHASE COST OF WATER DISTRICT 125 FOSTER POINT BRIDGE PIPELINE
7 ADD HYDRANTS AND SERVICES TO EXISTING 18" TRANSMISSION•MAIN
8"= 360.00
10" = 370.00
12 "= 380.00
TABLE 3
PIPE INVENTORY
TOTAL=
47761
NOTES:
1990 UNIT PRICE 8' = 560.00 10' = 570.00
1 SUPPLY CONNECTION TO BN PIPELINE
2 EXISTING PRV STATION TO BE REPLACED BY CONNECTION
3 4 INCH DI ON DUWAMISH RIVER FOOT BRIDGE TO BE ABANDONED
4 EXISTING BN HYDRANT LINE
5 EXISTING WATER DISTRICT NO. 125 PIPELINE
6 PURCHASE COST OF WATER DISTRICT 125 FOSTER POINT BRIDGE PIPELINE
8 ALTERNATE 18' SUPPLY INCLUDING PRV WOULD BE IN PLACE OF PIPE NOS. 215
AND 216. THIS WOULD ADD APPROX. 5140,600 TO TOTAL PROJECT COSTS.
12'= 580.00
$2,541,100.00
18'= 5100.00
$2,090,500.00
TABLE 3 (Continued)
PIPE INVENTORY
5450,600.00
•
DISTRICT 25
SYSTEM
ZONING
ULTIMATE
SIZE
REPLACEMENT
PHASE 1
PHASE 2
PIPE
NO.
LENGTH SIZE(IN.)
(FEET) MATERIAL
SIZE
(INCHES COST
SIZE
(INCHES) COST
SIZE UNIT
(INCHES) PRICE
ALONG II FROM
PTO
(INCHES)
244
46th Ave. S. S. 122nd St.
Northerly 470'
470
4 PVC
8
8
528,200
8
528,200
50
245
S. 122th St. 45th Ave. S.
46th Ave. S.
200
4 CI
10
10
514,000
10
514,000
50
246
S. 122th St. 46th Ave. S.
47th Ave. S.
250
4 CI
10
10
517,500
10
517,500
50
247
S. 122nd St. 47th Ave. S.
48th Ave. S.
250
4 CI
10
10
517,500
10
517,500
50
248
S. 122nd St. 48th Ave. S
49th Ave. S.
250
4 CI
10
10
517,500
10
517,500
SO
249
S. 118th St.. 44th PI. S.
BN Pipeline
540
NONE
10
10
537,800
10
537,800
50
250
44th Pl. S. S 118th St.
S. 122nd St.
1850
2 ST
8
8
5111,000
8
5111,000
SO
251
S. 118th St. 44th Ave. S.
44th PI. S.
100
2 ST
8
8
56,000
8
56,000
SO
252
S. 124th St. 44th Ave. S.
45th Ave. S.
230
4 CI
12
12
518,400
12
518,400
SO
253
S. 124th St. 45th Ave. S.
46th Ave. S.
250
4 CI
12
12
520,000
12
520,000
50
254
S. 124th St. 46th Ave. S.
47th Ave. S.
240
4 CI
12
12
519,200
12
519,200
50
255
S. 124th St. 47th Ave. S.
48th Ave. S.
250
4 CI
12
12
520,000
12
520,000
SO
256
S. 124th St. 48th Ave. S
49th Ave. S.
250
4 CI
12
12
520,000
12
520,000
50
2.57
S. 124th St. 49th Ave. S.
50th PI. S.
330
4 CI
12
12
526,400
12
526,400
SO
258
46th Ave S. & S. 125th St. S. 124th St.
50th Pl. S.
1340
2 ST
8
8
580,400
8
580,400
50
259
50th PI. S. S. 125th St.
S. 129th St.
1540
4 CI
12
12
5123,200
12
5123,200
50
260
50th PI. S. S. 125 th St.
S. 124th St.
200
4 CI
12
12
516,000
12
516,000
50
261
S. 124th St. 50th Pl. S.
SIth P1. S.
350
4 CI
8
8
521,000
8
521,000
SO
262
51st Pl. S. S. 124th St.
End
850
2 ST
10
10
559,500
10
559,500
SO
263
S. 124th St. (easement) 51th PI. S.
BN Pipeline
370
NONE
10
10
525,900
10
525,900
50
264
BN Pipeline S. 124th St. (easement)
S. 129th St.
1380
10 (4)
10
50
50
50
265
45th Ave. S. S. 129th St.
Easterly 620'
620
NONE
12
12
549,600
50
12
549,600
266
56th Ave S. S 133rd St.
Easterly 600'
600
2 ST
12
12
- 548,000
12
548,000
SO
268
S. 133rd St. & 57th Ave. S. 56th Ave. S.
S. 130th P1.
600
2 ST
8
8
536,000
8
536,000
50
270
S. 130th PI. 57th Ave. S.
Easterly 1060 '
1060
6 ST (5)
12
12
584,800
12
584,800
50
271
S. 130th Pl. 56th Ave. S.
57th Ave. S.
440
NONE
12
12
535,200
12
535,200
SO
272
56th Ave. S. S. 130th PI.
S. 133rd St.
800
2 ST
12
12
564,000
50
12
564,000
274
S. 124 St. 43rd Ave. S.
44th Ave. S.
270
4 CI
8
8
516,200
8
516,200
50
275
S. 122nd St. 46th Ave. S.
46th Ave. S.
50
4
10
10
53,500
10
53,500
50
276
BN Pipeline S. 124th St. (easement)
S. 118th St. (easement)
2650
10 DI (4)
10
50
SO
50
277
BN Pipeline S. 118th St. (easement)
S. 116th St. (easement)
1060
10 DI (4)
10
50
50
50
51st Ave. Beacon Ave.
S. 113th St.
500
6 CI
8
8
530,000
8
530,000
S. 114th St. 51st Ave. S.
49th Ave. S
1000
6 CI
8
8
560,000
8
560,000
S. 113th St. & 52nd Ave. S. 51st Ave. S.
S. 114th St
600
2 STL
8
8
536,000
8
536,000
51st Ave. S. 114th St
southerly to SWD
800
2 STL
8
8
596,000
8
596,000
282
S. 124th St. 42nd Ave. S.
42nd Ave. S.
40
NONE
12
12
53,200
12
53,200
SO
283
S. 144th St. 40th Ave. S.
End
1000
4 PVC
8
8
560,000
8
560,000
SO
284
S. 116th St. 38th Ave. S.
E. Marginal Way
150
NONE
10 .
10
510,500.00
10
510,500.00
50.00
S.115 & E. Marginal Way 42nd Ave. S.
S. 112th
2800
NONE
18(8)
18(8)
(5310,000.00)
18(8)
(5310,000.00)
TOTAL=
47761
NOTES:
1990 UNIT PRICE 8' = 560.00 10' = 570.00
1 SUPPLY CONNECTION TO BN PIPELINE
2 EXISTING PRV STATION TO BE REPLACED BY CONNECTION
3 4 INCH DI ON DUWAMISH RIVER FOOT BRIDGE TO BE ABANDONED
4 EXISTING BN HYDRANT LINE
5 EXISTING WATER DISTRICT NO. 125 PIPELINE
6 PURCHASE COST OF WATER DISTRICT 125 FOSTER POINT BRIDGE PIPELINE
8 ALTERNATE 18' SUPPLY INCLUDING PRV WOULD BE IN PLACE OF PIPE NOS. 215
AND 216. THIS WOULD ADD APPROX. 5140,600 TO TOTAL PROJECT COSTS.
12'= 580.00
$2,541,100.00
18'= 5100.00
$2,090,500.00
TABLE 3 (Continued)
PIPE INVENTORY
5450,600.00
V. NEEDED IMPROVEMENTS AND COST
The Future System Map shows a pipe distribution system for the area which is based on the City
of Tukwila's current zoning and minimum design standards. All pipeline design should be
consistent with this Plan, except as future zoning changes may require increased pipe sizes.
The existing 18 -inch City of Tukwila transmission main, the 10 -inch BNRR main and the
proposed 10 -inch and 12 -inch connecting mains form a base grid system for the main portion of
the District. Hydraulic analysis of this system indicates fire flows of at least 3000 gpm will be
available throughout the area upon completion of the recommended pipe replacements.
Although the SKYWAY CWSP suggest that the terms of customer /service area transfers are to
be determined by interlocal agreement between the parties involved, it is expected that the pipes
in areas designated for service by others will need to be brought up to the standards of the
receiving utility prior to the transfer. This can be done as part of an overall replacement program
or as a transfer area upgrade with all the lines in each transfer area done at once. In both cases
transfer would occur as soon as all lines in the area were replaced. Since it will depend upon the
receiving utilities existing facilities, the exact system configuration in these areas is not known.
For this study we have anticipated the existing lines will be replaced in current locations.
It may become necessary to re- establish the District's source of supply at East Marginal Way and
South 112th Street. This would provide a reliable backup to City's 18 -inch transmission line
through BNRR property. This line is shown as an alternative on the Future System Map and
included in the pipe listing. Since the area between this source of supply and the main service
area is currently under consideration for development, developer contributions to the system
could reduce the cost of re- establishing this source. Coordination with the Seattle Water
Department will be necessary to determine the quantity of water available and the best method
of establishing a Tukwila connection at this location.
Table 3 (pages 9 -10) lists every pipe within the Water District No. 25 area except for the City
of Tukwila 18 -inch transmission main. Also included are future pipelines which do not now exist
and estimated 1990 replacement cost for each pipeline.
11
The approximate 1990 cost to entirely replace the existing system is $2,541,100. Included in the
total is the purchase of the Foster Point Bridge crossing from Water District 125, which is
estimated at approximately $100,000. Construction of the alternative 18 -inch supply will add
approximately $140,600 to the total.
If the City chooses to replace these lines with an overall replacement program without
consideration of the area transfer to other utilities, the replacement could be phased to reduce the
impact to the City. Phase One would be the replacement of all of the old 2 -inch and 4 -inch pipe
and the integration of the system into Tukwila's supply. Also included is the connection to the
BNRR main and the straightening out of the multiple purveyor pipes on Foster Point. The 1990
cost for Phase One is approximately $2,090,500. It is expected this Phase could be spread over
several years time or could be constructed as a whole depending on financial resources available.
Final upgrading to Tukwila Standards and improving the distribution /transmission system would
be Phase Two. The 1990 cost for this phase is approximately $450,600. Construction of the 18-
inch alternative supply line would add approximately $140,600 to this amotint.
The City could choose to upgrade the individual transfer areas as separate phases of the overall
replacement program. The 1990 cost to replace the lines East of I -5 in their current location is
$222,000. West of the river the 1990 replacement cost is $202,000. The remainder of the total
cost is divided into the two phases as previously described. Phase One would therefore cost
$1,666,500 with Phase Two costing the remaining $450,600.
It is anticipated that storage for the area would be provided by the City of Tukwila's storage
facilities, primarily the West Hill Tank. Storage for the transfer areas would be the responsibility
of the receiving utility.
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IMPLEMENTATION AND FINANCING
Dissolution and Assumption
The dissolution of Water District No. 25 and assumption of its territory and responsibility by the
City of Tukwila requires the following steps:
1. Negotiation of an Agreement - The first step in the dissolution and assumption process
is the negotiation of the terms of transfer of the District's assets and liabilities to the City.
Items to be considered in the negotiations include, but are not limited to: the transfer of
titles to the property, facilities, and equipment; discharge or assumption and transfer of
indebtedness and assessments; and, the distribution of assets and liabilities. The
agreement should be passed by resolution, pending the successful completion of steps 2
and 3 below.
King County Boundary Review Board (BRB) Approval - After an agreement has been
reached, a notice of intention must be filed with the King County Boundary Review Board
in accordance with RCW 36.93. The notice of intention must include a description of and
reasons for the proposed action; signed and certified copies of the resolution /ordinance
accepting the proposal; SEPA documentation (unless the proposal is considered
categorically exempt); a legal description of the boundaries proposed to be created,
abolished or changed; and maps showing the vicinity . of the proposal, affected property,
current corporate limits, etc. In addition, applicants are required to provide the Boundary
Review Board with information on population and densities, assessed valuations, land use,
relationship to plans and policies, revenues and expenditures, provision of services etc.
Upon filing of a notice of intention, a period of forty -five days is allowed for comments
on the intention and request for review by the BRB. If no requests for review are
received within that period, the proposal is deemed automatically approved. If review
of the proposal is requested, the BRB is required to make a finding within one - hundred
twenty days after the request for review has been filed.
3. King County Superior Court - After approval of the proposal by the BRB, a petition must
be made to the King County Superior Court in accordance with RCW Chapter 35.13A.
13
The court may grant an order of dissolution without a public hearing, provided that:
The petition is authorized by both parties;
Titles to the property, facilities and equipment of the District have passed to the
City;
All indebtedness and local improvement district or utility local improvement
district assessments of the District have been discharged or assumed by and
transferred to the City;
The petition contains a statement of the distribution of assets and liabilities
mutually agreed upon by the City and the District, and a copy of the agreement
between the City and the District; and,
The court is satisfied that the interests of and all interested parties have been
protected.
4. Resolutions and Ordinances - Upon approval by the BRB and recording of the dissolution
and assumption in the Superior Court, the District and City must pass the required
resolution /ordinance solidifying the agreement for transfer of assets and liabilities and
providing for the management and control of water service within the transferred area.
5. Transfer of Customers - As outlined in Section IV (Needed Improvements and Costs) of
this report, future service to customers west of the Duwamish is to be provided by King
County Water District No. 125. The customers in the area of the District which is east
of Interstate 5 are to be served by the City of Seattle. Before transfer of customers can
occur, it is anticipated that the facilities in these areas must be brought to the standards
of the future purveyor. The City can then either contract with these entities for provision
of service by interlocal agreement, or actually eliminate these areas from their service
area and transfer service responsibility to the receiving purveyors. If the latter option is
taken, additional Boundary Review submittals are required.
Financing
The Draft Environmental Impact Statement prepared for the Fire District No. 1 Annexation
(February, 1988) suggests that revenues from the increased tax base associated with the
annexation could be used to mitigate the cost of the Water District No. 25 system upgrade. The
annexation report, however, does not indicate how much of these revenues would actually be
14
dedicated to utility improvements. Assuming that some additional source of funding will be
necessary to complete the estimated $2.5 million of recommended improvements, a combination
of the following financing options should be investigated by the City:
- Formation of a Local Improvement District (LID);
- General Obligation or Revenue Bonds;
- Public Trust Fund Loans;
- Revenue from the Difference Between District and City Rates;
- Rate Surcharges;
- State Drought Relief Funding; and,
- Other Grant and Loan Money.
Localized improvement projects, such as that proposed for the Water District No. 25 system
upgrade, are commonly financed by forming a Local Improvement District (LID), with the
benefitting property owners financing the improvements by assessments. Formation of an LID
must have the support of the majority of the property owners, based on area. Provision for
adequate utility services was a major factor in voter approval of the annexation and in the
District's agreement to a takeover. Difficulty in obtaining LID approval may therefore be
anticipated.
General obligation bonds must have the support of the majority of voters. These bonds become
the assessments against the properties within the LID and are paid for by the assessments and
other funds available to the Water Department. Revenue bonds do not require voter approval and
may be paid off by whatever funds are available to the City for the payment of debt service. A
major source for these funds is from the imposition of LID assessments, however, all funds, such
as general fees or latecomer charges, may be used for the debt service for revenue bonds. Either
of these types of bond financing would be acceptable for financing the Water District No. 25
upgrade, but obtaining voter approval for general obligation bonds may be difficult.
Public Works Trust Fund funding is a low interest loan program which can be used to finance
water system improvements of up to $2.5 million. Interest rates range from 1% to 3 %,
depending on the level of local participation and must be paid off within twenty years.
15
Applications for 1991 Public Works Trust Funds must be submitted by July 21, 1990.
Imposing a rate surcharge to the customers affected by the proposed system improvements is
another possible method of financing. The City of Tukwila's rate structure, however, provides
reduced rates for low income elderly customers and approximately 5% of the Allentown area
residents are likely to qualify for this type of assistance. This will limit the benefits realized from
imposing a rate surcharge. Additionally, when the City takes over the system, there will be a rate
increase of approximately 15% for Water District No. 25 customers. This will result in some
additional revenue that could be used to help finance the needed improvements.
Drought Relief Funding is intended to provide financing for studies and projects which provide
water conservation measures. Types of projects typically financed by this program are
categorized into Preventive and Remedial Grants. Water systems are limited to a maximum of
$160,000 from each category. Preventive grants are generally 40% financing (except interties -
20%) and include projects such as water shortage response planning, leak detection studies, flow
restricting devices, source monitoring equipment, interties and implementation of conservation
programs. Remedial grants are allocated only if a utility is experiencing a water shortage.
Funding amounts for remedial grants range from 20-40% depending on the demonstrated severity
of a water shortage and are available for source development and rehabilitation, treatment
equipment, emergency trucking of water supply, repairs to reduce water loss etc. Although
Drought Relief funding is determined on a case by case basis, no funds have been allocated for
pipeline replacement projects. This type of funding could, however, be used for water shortage
response planning, leak detection study, and ultimately, prioritizing pipeline replacements. Before
funding can be obtained for leak detention or any other purpose, a water shortage response plan
identifying the reason for such additional studies /projects is required.
Although Federal and State grant funding for water system projects has become increasingly
scarce in recent years, there are still viable options for this type of financing for the Water
District No. 25 system improvements. The U.S. Department of Housing and Urban Development
(HUD) administers a block grant program, which provides funding for a variety of community
development projects, including water systems. These funds are available for low and moderate
income areas as defined by HUD. Community block grant funding for this area is coordinated
16
by the King County Community Development Division. As a "pass through" city, a share of the
County's annual Block Grant funding is given to Tukwila. Approximately $55,000 is expected
from this source for 1991. Historically, these funds have not been dedicated to funding utility
projects and therefore have not been considered as a viable funding source at this time.
Other grants that may be available include Community Economic Revitalization Board funding
from the State, and Federal Economic Development Funding. These grants are specific cause or
justification.
The State Community Economic Revitalization Board (CERB) provides loans (and occasional
grants) for public works projects required to support private sector development which will create
jobs and /or strengthen an area's economy. Applications for this type of funding must prove that
a specific development is ready to occur, will not occur unless CERB funding is provided and that
no other timely source of funds is available. There are no project limits on CERB funding and
interest rates can be as high as 10% depending on bond ratings. Although CERB funding may
benefit the ,City in the future, lack of private sector development applications at this time
precludes it from consideration in the financing alternatives examined in this report.
Federal Economic Development Administration (EDA) grant funding is also a viable source of
monies for areas which are in need of economic revitalization. To receive this type of funding,
the City would have to demonstrate that the installation of public services would result in
redevelopment of the Allentown area and subsequent creation of job opportunities. EDA grant
funding amounts vary according to the economic climate of an area. Grants in King County are
typically 50 %, but 60 -80% funding could be obtained if the application for funding demonstrates
a higher unemployment rate than in the rest of the County. In that redevelopment of Allentown
would require rezone of the area, EDA funding has not been considered in the financing
alternatives for this study. If rezone of the area does occur, however, this option should be
explored for both sewer and water improvements in the area.
17
VII. FINANCING AL7ERNA77VES r
Recommended Financing Program
The recommended financing program for the required replacement of the Water District No. 25
system includes increased revenues from the difference between exiting Water District No. 25 and
the current City of Tukwila water rate schedule; State drought relief funding; and, Public Works
Trust Fund loan money. A summary of the funds available from each of these sources is as
follows:
Funds Available From Increased Rates
Public Works staff have indicated that the revenue generated by the Water District 25 customers
that exceed the existing Water District 25 rates could be used for needed improvements in that
area. Amount of increase revenue, generated from this source is estimated in Table 4. Estimated
revenues are based on an average monthly use of 1000 cubic feet per month per connection.
TABLE 4
ES77MA7ED RATE INCREASE REVENUES
1990* 1991 1992 1993 1994 1995
Estimated Residential
Equivalents 497 500 503
Estimated Revenue Based Assume 5% Increase
on Tukwila Rates $49,281 $89,466 $96,653 Per Year
After 1992.
Estimated Revenue Based
on W.D. 25 Rates $42,444 73,200 73,639
Estimated Revenue
Increase $ 6,837 $16,246 $23,014 $24,165 $25,373 $26,642
* Starting June 1, 1990
State Drought Relief Funding
Additional grant funding could be obtained from the State Drought Relief Funds. This would be
a 40% grant to accomplish a water shortage response plan and leak detection study. These studies
would establish the location and estimated amount of various leaks in the aged Water District No.
25 system. In this manner, the priority of upgrading the system could be established. This also
would establish a plan to reduce water loss in the system and program to upgrading the system
18
as funds become available. It is estimated that the water shortage response plan and leak
detection study report could be accomplished for about $19,000 for the Water District 25 area.
Assuming a 40% grant the City would need $11,400 for their contribution to the study plus the
cost for preparing an application (approximately $1,000).
Public Works Trust Fund
Public Works Trust Funds could be used to maximize the use of the revenue generated. Public
Works Trust Loans are available with 1 %, 2% or 3% repayment interest rates, depending on the
amount of matching funds provided by the City. Because of the limited amount of funds available
for the required local match, it is assumed that the City will obtain a 3% Public Works Trust
Fund loan with 10% local match funding.
Table 5 details the amount of surcharge needed to payback a 3% interest rate Public Works Trust
loan with a 10% local match borrowed at a 8% interest rate. It assumes that the loans will be
paid back over a 20 year period using the increased revenue estimated in Table 4. As indicated,
as much as $350,000 of improvements could be financed from these projected increased revenues.
If a more aggressive plan for system replacement were pursued, additional sources of funding will
be required. Table 5 also illustrates the annual deficit of funds required to finance various levels
of Public Works Trust funding.
Project
Cost
TABLE 5
RECOMMENDED FINANCING ALTERNATIVE
ANNUAL COSTS
10% Local Match Public Works
Repayment Trust Repayment
8% Interest 3% interest
$ 250,000 $ 2,250 ± /Yr.
300,000 $ 2,700
350,000 3,150
400,000 3,600
450,000 4,050
500,000 4,500
750,000 6,750
1,000,000 9,000
1,500,000* 13,500
$14,625 + /Yr.
17,550
19,475
23,400
28,575
29,250
43,875
58,500
87,750
Total
Annual
Repayment
$16,875
20,250
22,625
27,000
32,625
33,750
50,625
67,500
101,250
* Maximum Public Works. Trust Fund loan in a given year.
19
Increased
Revenue Annual
due to rates Deficit
$23,000 + /Yr. $ 0
23,000 $ 0
23,000
23,000
23,000
23,000
23,000
23,000
23,000
$ 0
$ 4,000
$ 9,625
$10,750
$27,625
$44,500
$78,250
Advantages of Recommended Financing Plan
. Maximize use of available funds for needed improvements.
. Will eliminate majority of health, safety and welfare issues initially with a Phase 1
improvement
package.
. Maximize use of money to upgrade and replace the system.
Disadvantages of Recommended Financing Plan
Requires commitment by City to appropriate initial matching funds.
Funds available from the increased revenues generated from rates limits the amount of work
that can be accomplished without additional financing.
Additional funding required to complete all of the required system improvements.
Financing Alternatives
Financing Alternative I - Increased Rate Revenue Financing
As an alternative to the Public Work Trust Fund financing program discussed previously,
the required improvements could be funded using a "pay as you go" approach utilizing
the money obtained form the difference between the existing Water District No. 25 rates
and the current and projected City of Tukwila water rates. As presented in Table 4, the
projected revenues from rates are estimated at approximately $23,000 annually.
Additional State Drought Relief funding of approximately $8,000 could also be used
under this financing alternative.
These available funds would be utilized to conduct the Leak Detection Study, install fire
hydrants and upgrade and repair the system on the established priority basis. It is
assumed that where the leaks are repaired, replacement segments will be to the size and
standards setforth in this plan. Repair of leaking lines without actually upgrading and
improving the system is not recommended except for emergencies because it would result
in using money that would be better for replacement. A suggested implementation plan
for financing Alternative 1 is as follows:
20
TABLE 5
FINANCING ALTERNATIVE 1 SUMMARY
1990 -91 1992 1993 1994 1995
ESTIMATED REVENUE
Rate Increase $23,083 23,014 24,165 Assume 5 %/Year Increase
Drought Relief Grant 8,000
Est. Available Monies $31,083 23,014 24,165 $25,373 $26,642
RECOMMENDED IMPROVEMENT PLAN
Drought Relief Grant
Application and Water
Shortage Response Plan $ 4,000
Leak Detection Plan 15.000
Fire Hydrants* 10,000
FUNDS AVAILABLE FOR SYSTEM
IMPROVEMENTS ** $ 2,083 $23,014 $24,165 $25,373 $26,642
* Assume 2 hydrants installed off existing 18" on east side of 42nd Ave. S., or, 5
hydrants installed on west side of street.
** Estimated funds available for improvements to be used for system upgrade as
prioritized by the leak detection study. Worst leaks would be replaced first.
Advantages of Financing Alternative 1
. Provides a minimum plan utilizing anticipated funds available without raising rates.
(Pay as you go plan).
. Establishes a plan to fix the worst problems first on a priority basis.
Disadvantages of Financing Alternative 1
Most improvements will not be made for many years.
Piece meal approach will result in a significant increase in ultimate replacement cost
of the system.
System leaks and monetary loss due to lost water will continue for many (50 +) years.
(Potential health & safety hazards due to leaks).
Inadequate water service and fire protection will continue for many (50 +) years.
21
Project
Cost
Financing Alternative 2 - Rate Surcharge Financing
Another alternative for financing construction of the needed improvements is to add a
surcharge to the rates for the Water District No. 25 area. This financing alternative is
similar to the recommended financing alternative except that it considers using rate
surcharges to finance repayment of a larger Public Works Trust Fund loan. Revenue
created in this fashion could be in addition to that revenue generated from the rate
difference discussed earlier. It is estimated each dollar of rate surcharge for the Water
District No. 25 area would create about $5800 /year that could be used for system
improvements. For example: If the City imposed a $5 /month/customer surcharge,
approximately $29,000± could be anticipated to help finance needed improvements.
TABLE 6
FINANCING ALTERNATIVE 2
SUMMARY OF ANNUAL COSTS
10% Local Match Public Works Total
Repayment Trust Repayment Annual
8% Interest 3% interest Repayment
$ 250,000 $ 2,250 ± /Yr.
300,000 $ 2,700
350,000 3,150
400,000 3,600
450,000 4,050
500,000 4,500
750,000 6,750
1,000,000 9,000
1,500,000* 13,500
$14,625 ± /Yr.
17,550
19,475
23,400
28,575
29,250
43,875
58,500
87,750
$16,875
20,250
22,625
27,000
32,625
33,750
50,625
67,500
101,250
* Maximum Public Works Trust Fund loan in a given year.
Increased Rate
Revenue Surcharge
due to rates (per Connection)
$23,000 + /Yr.
23,000
23,000
23,000
23,000
23,000
23,000
23,000
23,000
$0
$0
$0
$ 0.67 /month
$ 1.61 /month
$ 1.80 /month
$ 4.63 /month
$ 7.46 /month
$13.12 /month
Based on the above Table 6, the City could select a Phase 1 budget and determine the rate
surcharge needed to fund the improvement.: For example, if a Phase I improvement
program was set at $ 1,000,000 with a 3% Public Works Trust loan to finance the work,
the following would be needed: Repayment of the 10% local match at about $9,000 per
year over 20 years (at 8% interest); and Repayment of the 3% Public Works Trust Fund
loan at $58,500 per year over 20 years. Repayment would be by an estimated
$23,000 /year generated from increased rates and a $7.46 /month/connection surcharge for
the Water District 25 customers. Other combinations can be estimated using these tables.
Surcharges are estimated assuming that the approximately 500 customers in the Water
22
District No. 25 area will pay an equal surcharge, regardless of the amount of water used.
Advantages Financing Alternative 2
Maximize use of available funds for needed improvements.
Will eliminate majority of health, safety and welfare issues initially with a Phase 1
improvement package.
Maximize use of money to upgrade and replace the system.
Disadvantages of Financing Alternative 2
Requires commitment by City to appropriate initial matching funds.
Requires rate surcharge to accomplish the majority of the work required in the area.
Financing Alternative 3 - Local Improvement District Financing
A third alternative is to establish an Local Improvement District (LID) to fund the Phase
I needed improvements. Similarly to the Recommended Financing Plan, Public Works
Trust funding could be used to reduce the interest rate for the LID. The LID could be
established by either petition or resolution method and could be for a portion of the entire
system improvements. Revenue bonds would be sold for any additional funding required.
Advantages of Alternative 3 Financing
Maximize use of available funds for needed improvements.
Will eliminate majority of health, safety and welfare issues initially with a Phase 1
improvement package.
Maximize use of money to upgrade and replace the system.
. Eliminate majority of loss water and associated lost revenue with Phase 1
improvements.
. Would not necessarily require a rate increase or affect monthly rates.
. Can use Public Works Trust Funds, assessments, money from rates, etc., to payoff
bonds.
23
Disadvantages of Alternative 3 Financing
. Would require over 51% of property owners sign petition or less than 40% protest if
resolution method is utilized.
Other Funding Options
As the area continues to develop or redevelop, developers will be required by the City to install
needed improvements for their projects that would upgrade portions of the overall system for the
benefit of existing customer. Additionally special grants such as Community Economic
Development Revitalization Board Economic Development Administration funding may be
available for specific types of development. These system improvements can not be scheduled
as they will occur based on economic climate and rate of development.
24