Proposed Tacoma Water partnership with the Cascade Water Alliance
The Agreement
Tacoma Water is negotiating a proposed wholesale water supply agreement with the Cascade Water Alliance (Cascade). Under this proposed agreement, Tacoma Water would deliver water to the edge of our service territory. Cascade would then deliver this water to their members.
If approved, Tacoma would start delivering water to Cascade in 2041. Delivery amounts and time frames are still being negotiated, but Cascade could start with a small portion of water in 2041 and steadily increase to 24 million gallons per day on average by 2060. After 2062, delivery to Cascade would be reduced to 12 million gallons per day (MGD) on an average day.
Currently, there is no infrastructure connecting the Tacoma and Cascade systems. Cascade would need to construct a water transmission main from Tacoma’s pipeline 5 to Cascade’s customers.
Click here to learn more about the Cascade Water Alliance and their plans for future supply.
Timeline
- 2025
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Tacoma and Cascade execute a temporary wholesale contact providing Cascade up to 12 MGD-Average Day and 17.5 MGD-Peak Day from 2041 to 2062, pending Public Utility Board and City Council approval.
Tacoma and Cascade execute a permanent wholesale contact providing Cascade up to 12 MGD-Average Day and 15 MGD-Peak Day, pending Public Utility Board and City Council Approval.
- 2030
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Cascade begins design and construction of their transmission system.
- 2041
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Cascade’s Transmission system is completed and water delivery from Tacoma begins.
Delivery will start small (1 or 2 MGD) then increase slowly until reaching up to 24 MGD-Average Day and 32.5 MGD-Peak Day in the early 2060s.
- 2062
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The temporary supply to Cascade ends. Deliveries to Cascade will not exceed 15 MGD-Peak Day.