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 are moving forward with an eight-year capital improvement project to update the Washington Park Reservoir site at 2403 SW Jefferson Street.
Engineered for Seismic Resiliency
Washington Park’s open-air reservoirs were built over 120 years ago and the complex gravity-fed drinking water system remains a valuable and innovative resource for the City.
The Washington Park Reservoir Improvement Project entails building a new, seismically reinforced below-ground reservoir. The reservoir will not only maintain the historic gravity-fed 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.
Aside from protecting our precious resource, this project will allow park visitors to enjoy many of the preserved historic elements as well as some exciting new additions. A reflecting pool will sit atop Reservoir 3 and many of the original structures will be maintained. Reservoir 4 will be disconnected from the drinking water system, and another reflecting pool along with a wet prairie habitat area will be constructed in the basin.
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.
Currently the construction team is working to fill Reservoir 4 to support the future habitat area and reflecting pool.
Sacajawea Boulevard is temporarily closed while two shoring walls are built along it. These will provide construction access while the new reservoir is constructed. A temporary access ramp into Reservoir 3 was constructed for equipment and material access into the reservoir. Ongoing work includes erosion control at the construction site, installation of a receiving pit and boring 48” diameter casings under the Reservoir 3 dam, and removal of the wetwell in Gatehouse 4.
Learn more about road closures and how to navigate Washington Park during this improvement project.
Questions or concerns?