Seattle Public Utilities

Reservoir Covering


Beacon Reservoir and Jefferson Park construction in 2009.

What & Why

Seattle Public Utilities (SPU) has replaced six of its open reservoirs with underground structures that will improve the quality and security of our water supply. Following SPU’s reservoir covering projects, Seattle Parks and Recreation Department constructed recreational open space improvements over the covered reservoirs, providing The reservoir covering program provided 90 acres of new open space. Reservoirs that have been replaced with underground structures and new open space areas include Magnolia (1995), Lincoln (2004), Myrtle (2008), Beacon (2009), West Seattle (2010), and Maple Leaf (2012).

Seismic reviews of the West Seattle, Maple Leaf, Myrtle and Beacon Reservoirs indicated that they all required a retrofit to the floor slab perimeter. No new excavation work will be needed for these retrofits. The work will be done inside the reservoirs via existing access hatches.

What’s happening now?

Seismic Retrofits

The retrofit projects for West Seattle, Maple Leaf and Myrtle Reservoir have been completed. The Beacon Reservoir retrofit project is expected to start construction in January of 2017. No new excavation work will be needed for this retrofit. The work will be done inside the reservoir via existing access hatches. Utility rates will be unaffected by the project.

Decommissioning Test

SPU has decommissioned the Volunteer and Roosevelt Reservoirs to study the impact the out-of-service facilities have on Seattle’s overall drinking water system, make evaluations, and determine whether these reservoirs can be permanently taken out of service.

Find out the latest information on the Volunteer Reservoir decommissioning.

Find out the latest information on the Roosevelt Reservoir decommissioning.