HomeMy WebLinkAboutTIS 2021-01-25 Item 2B - Update - Land Purchase for Water Reservoir and Pump Station
https://tukwilawa.sharepoint.com/sites/publicworks/engineering/PW Drop Box/01 TIC Agenda/2021 Agenda Items/01 -25-21 TIC/1. Water Reservoir and Pump Station/Info Memo Reservoir Site Land Purchase.docx
INFORMATIONAL MEMORANDUM
TO: Transportation and Infrastructure Services Committee
FROM: Hari Ponnekanti, Interim Public Works Director
BY: Adib Altallal, Utilities Engineer
CC: Mayor Allan Ekberg
DATE: January 22, 2021
SUBJECT: Water Fund – Water Reservoir and Pump Station
Project No. 91240102
Land Purchase Update
ISSUE
Authorize Public Works to begin negotiations with owners to purchase property for a future water reservoir.
BACKGROUND
During the City of Tukwila’s 2015 Water Comprehensive Plan, the consultant identified that the continued growth within the
City no longer meets the Department of Health’s water storage requirements. As a result, the Water Reservoir and Pump
Station was included in the Capital Improvement Program. During this year’s Water Comprehensive Plan update, the City’s
water storage deficiencies were highlighted again. A water reservoir is needed to meet the Department of Health’s water
storage requirements. Further development throughout the City and especially in the Ryan Hill area are likely to be hindered
or completely halted due to these water storage deficiencies.
ANALYSIS
By constructing a reservoir in the Ryan Hill area, the City would meet the Department of Health’s water storage requirements.
By placing the reservoir in the Ryan Hill area, the City would be using the natural topography to increase the use of gravity
and reduce pumping costs. Furthermore, placing a tank in the northern half of the City will complement the existing reservoir in
the southern half. Connecting the Ryan Hill water zone to the rest of the water system will also expand fire protection for
residential and commercial properties as well as create a redundant water supply that can be utilized in the event of a natural
disaster. To construct a water reservoir and a pump house, a property consisting of one to two flat acres is needed. For design
and subsequent construction of the reservoir to commence, land must be purchased first. The City will work diligently to
acquire property through negotiating a purchase with property owners with the goal to avoid the use of eminent domain. Time
is of the essence to begin negotiations. Once land is acquired, the project will be completed in phases over multiple years.
FISCAL IMPACT
The adopted 2021 Capital Improvement Program identified an estimated project budget of $10 million for the Water Reservoir
and Pump Station, a portion of which was dedicated to land acquisition. As land costs escalate in the region, we have the
potential to find a larger property and sell a portion of the property after the reservoir has been built, for a net match of the
budgeted amount dedicated to the land purchase.
Land Purchase 2021 CIP Budget
Water Reservoir Site $2,000,000.00
Future Sale of portion of site ($1,500,000.00)
Total $ 500,000.00 $500,000.00
RECOMMENDATION
Information only. Public Works to begin land purchase negotiations as part of the Water Reservoir and Pump Station Project
in an amount up to $2,000,000.00.
Attachments: 2021 CIP Page 60
PowerPoint Slides
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Tukwila Water System Storage Needs
A brief history and a future outlook of Tukwila’s water system storage facilities
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Overview
•Service area boundaries
•North Hill Reservoir/Pumpstation
Tukwila Water Dept. Distribution System
•Cascade Water Alliance/SPU
•Previous comprehensive plans storage requirements
Tukwila Water Dept. Historical Data
•Current storage deficit
Current Comprehensive Plan
•Resiliency
•Future development
•Changing demographics
Planning For The Future
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City of Tukwila Distribution System
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Pressure Zones
➢320 pressure zone~ Northern portion of East Marginal Way (Mainly serves Boeing properties)
➢340 pressure zone~ Lower Ryan Hill/MLK Jr. Way (Fed by 465 pressure zone)
➢360 pressure zone~ CBD, Valley floor (Largest zone by area and connections)
➢380 pressure zone~ Crystal Springs (Smallest zone, isolated from main distribution system)
➢400 pressure zone~ North Hill (Most residential connections, fed by North Hill Reservoir, can
be fed by 360 zone)
➢465 pressure zone~ Upper Ryan Hill (Isolated from main distribution system)
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Cascade Water Alliance/SPU
Tukwila Water
Department is a member
of Cascade Water Alliance.
Cascade is a group of eight
water municipalities
formed to provide water
supply for the current and
future demands of the
members.
Tukwila receives 100% of
their water through
supply stations connected
to Seattle Public Utilities.
Tukwila has no means of
water production.
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North Hill Reservoir & Pump Station
➢Built in 1991 to provide storage, increase pressure, and improve fire flow
➢Built in phases
I.Property was identified and purchased
II.Construction of transmission main from Southcenter Blvd up the trail(Old Denny’s, Macau
casino) to 57th Ave S.
III.Construction of Transmission main along Tukwila Parkway from Andover Park East to
Bahama Breeze curve(old movie theatre) and then bored under neath I-405 to
Southcenter Blvd.
IV.Tank/pump station was under construction concurrent to the construction of the
transmission mains.
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North Hill Reservoir/Pump Station Specs
2015 Water Plan Storage Requirements
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2021 Water Plan Storage Deficits
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Properties
Assessed
Criteria:
➢Cost
➢Minimum Area
➢Access/Feasibility
➢Proximity to existing
distribution system
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Planning for the Future
➢Resiliency
❖Emergency water storage
❖Located in Northern portion of the water system.
➢Development
❖Allows safe residential and commercial development
➢Changing demographics
❖Increase in multifamily residences
❖Increase in commercial/retail space
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THANK
YOU!
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