Washington Park Reservoir construction updates

Capital Improvement Project
Under Construction
Construction at the Washington Park Reservoir started in 2016 and will continue until 2025. Read on for the most recent update.
Portland Water Bureau construction crews at work
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 April 4.

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Happening now

Working hours

  • Standard working hours start at 7 a.m. and end at 7 p.m. Monday through Friday.  
  • A noise variance has been approved, allowing work to start at 5 a.m. on days when crews will be pouring concrete.
  • During construction, you can expect noise from saws, excavation, dump trucks, concrete pump trucks, and generators. 
  • Weather may affect working hours and activities. 

Projects happening now

  • Pouring concrete for the grand staircase and reflecting pool 
  • Installing lowland habitat elements such as retaining walls, drainage, and overflow pipes 
  • Planning for road reconstruction and closures
  • Performing historic restoration of existing structures and fences
  • Constructing the lighted promenade, new walkways, retaining walls, and seat walls around reflecting pools 
Portland Water Bureau construction crews at work
Portland Water Bureau construction crews pouring concrete for the reflecting pool.

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 

Started in February 2022, the Water Bureau replaced 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. 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.