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The City of Portland, Oregon

Portland Water Bureau

From forest to faucet, we deliver the best drinking water in the world.

Customer Service: 503-823-7770

GENERAL INFORMATION: 503-823-7404

More Contact Info

Project Overview

The Portland Water Bureau is rebuilding the Washington Park reservoirs, a project that continues through 2024. Washington Park reservoirs have been in service since 1894. When completed, this project will supply water to Portland’s west side and serve more than 360,000 people, including all downtown businesses and residents, 20 schools, five hospital complexes, and more than 60 parks. This system of water conveyance and storage makes Portland a livable, and thriving community, ensuring public health and economic viability.  

This project is building a new 12.4-million gallon, seismically reinforced below ground reservoir, within the footprint of the existing Reservoir 3 (upper) with a reflection pool/water feature on top. While retaining the historic look and feel of the original reservoir, it has been engineered to withstand ongoing landside encroachment and potentially catastrophic effects of a major earthquake.

The existing Reservoir 4 (lower) is disconnected from the public drinking water system and is being developed into a lowland wildlife habitat area, bioswale, and reflection pool.

To view a rendering of the completed projected click HERE.

Comprehensive Schedule

Construction started Sept.12, 2016 and will proceed through 2020. A pause is scheduled to occur from 2020 to 2022 to allow soils to settle. From 2022 to 2024, construction of interpretive features, including the reflecting pool and surface features, will conclude the project. For a schedule of current activities see HERE.

Frequently Asked Questions

Area map with detours

Construction timeline

Project construction will proceed through 2019. A pause is scheduled to occur from 2020 to 2022 to allow soils to consolidate to reduce any vertical movement. From 2022 to 2024, construction of interpretive features, including the two reflecting pools and surface features, will conclude the project.

ACTIVITY Starting September 12, 2016 and lasting for 12 to 18 months (March 2018), major earthwork will occur along with the construction of shoring walls and the new underground reservoir.

Click here to access a Map of Park Impacts: September 12, 2016 - March 2018.
Work during this stage will cause temporary impacts to traffic, parking, and TriMet bus service. Later stages of the project with have varying impacts. Park users are encouraged to move safely around the park and its attractions. Please watch carefully for detours and signage and follow direction from flaggers.

Background

In order to comply with federal and state mandates and ensure a healthy, resilient, and secure water system, the Portland Water Bureau and Oregon general contractor Hoffman Construction Company began, in September 2016, an eight-year capital improvement project to update the Washington Park reservoir site at 2403 SW Jefferson Street.

Washington Park’s previously open Reservoirs 3 (upper) and 4 (lower) occupy the site along with two gate houses, a weir building, three pump houses, a generator house, and associated underground piping. The reservoirs were part of an ingenious gravity‐fed drinking water system constructed more than 120 years ago in 1893 and 1894, respectively. The system remained on-line for more than a hundred years before the current construction project began.

Reservoir 3 from the Grand Stairway: Existing 

Left - Pre-existing: Reservoir 3 from the Grand Stairway
Right - New Construction: Upper Reflecting Pool from the Grand Stairway

Reservoir 3 with Gate House 3: Existing 

 Left - Pre-existing: Reservoir 3 with Gate House 3
Right - New Construction: Upper Reflecting Pool at Gate House 3

The Washington Park Reservoir Improvements Project entails building a new, seismically reinforced underground reservoir. The reservoir will not only maintain the historic drinking water function provided by the original reservoirs, but will be engineered to withstand ongoing landslide encroachment and potentially catastrophic effects of a major earthquake and will feature a reflecting pool on top in the same general footprint as the historical Reservoir 3.

 Reservoir 4 View from Dam 3: Existing 

 Left - Pre-existing: Reservoir 4 View from Dam 3
Right - New Construction: Lower Reflecting Pool View from Dam 3

 Reservoir 4 View from Above at Sherwood Blvd: Existing 

 Left - Pre-existing: Reservoir 4 View from Above at SW Sherwood Blvd
Right - New Construction: Lower Reflecting Pool View from SW Sherwood Blvd

Reservoir 4 has been disconnected from the public drinking water system, and a lowland habitat area/bioswale and a reflecting pool will be constructed in the basin. Work will primarily be within the Historic District.

When complete and online, the new underground reservoir will supply water to Portland’s west side, including all downtown businesses and residents, the Oregon Zoo, more than 60 parks, six hospitals, and 20 Portland public schools; and provide fire suppression as well.

The project is part of the Water Bureau’s Capital Improvement Program and funded by revenue bond proceeds paid back with utility ratepayers’ fund.