Washington Park Reservoirs construction updates

Capital Improvement Project
Under Construction
Construction at the Washington Park Reservoirs started in 2016 and will continue until 2025. Read on for the most recent update.
This image shows an artist's rendering of what the reservoir site will look like after construction is finished, with reflecting pools, public walkways and lush vegetation. Text reads, "We're letting gravity do its thing. The soil needs to settle to ensure this project is successful. The next phase of work will begin late 2023. Additional text includes the project website, a description of the project, partner logos and accessibility statement.
2016 through 2025
On this Page


The Water Bureau has replaced its original 1894 reservoirs with a new 12.4-million-gallon, seismically reinforced underground reservoir. This reservoir supplies water to Portland's west side and serves more than 360,000 people, including all downtown businesses and residents, 20 schools, 5 hospital complexes, and more than 60 parks.

Currently we are working to install the reflecting pool and interpretive elements, restore historic structures and open the area to the public for the first time in decades. This page last updated October 27.

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Happening now

Working hours

  • Working hours for the fall and winter when temperatures are at their coldest start at 5 a.m. and end at 6 p.m. Monday through Friday.
  • During construction, you can expect noise from saws, excavation, dump trucks, concrete pump trucks, and generators.
  • Thank you for your patience while we work to improve your water system.

Projects happening now

  • Pouring concrete for the base and walls and walk ways around the reflecting pool
  • Constructing lowland habitat elements such as sidewalks, walls, and lampposts
  • Laying the groundwork for habitat plantings and hardscaping
  • Constructing the gatehouse and performing historic restoration of some existing structures and fences.
  • Conducting prep work, and pouring of the grand staircase.

Stay tuned for a grand celebration in 2025. In the meantime, enjoy this 360-degree panorama view taken from atop of the Reservoir 3 dam.

Construction Site

Map showing the northern portion of Washington Park, and the location of two work areas west of the tennis courts, and two work areas on the eastern edge of the Rose Garden along a maintenance road.
Map showing work areas.

Monitoring ground movement 

Starting in February 2022, the Water Bureau will replace some sensors in the park to help us measure ground movement of the slow-moving landslide between the Portland Japanese Gardens and Washington Park Reservoir. We installed some of these a few years back and are replacing them as part of ongoing maintenance. Our work will take place at a couple of locations within the reservoir construction site, on a maintenance road near the Rose Garden Amphitheater, and in the parking area next to the tennis courts. This work ensures that we can gather accurate information about soil movement near the reservoir as part of our seismic planning efforts.

This historic photo from the early 1900's shows two men standing on the Washington Park Reservoir Dam during construction. Text on the image reads, "We're letting gravity do its thing. The soil needs to settle to ensure this project is successful. The next phase of work will begin late 2023." Other text includes the project website, a short description of the reservoir project, and accessibility statement.

In addition to building new walkways and a reflecting pool, we'll plant native flowers and grasses, making a better habitat for wildlife, including butterflies. When we've completed the final stage, this park will transform into a vibrant public space we all can enjoy.

Curious about the soil settling process? Watch this informative video:

Park openings and closures

Visit the Explore Washington Park COVID-19 resource page for updated maps and information about Washington Park openings, closures, and safety.