Mount Tabor Reservoir 6 stabilization repairs underway

Portland Water Bureau crews will break ground today on work to restore Mount Tabor Reservoir 6 after weeks of planning and careful evaluation of bids to manage project costs.  

“I join Portlanders’ excitement in seeing crews break ground on the Mount Tabor Reservoir 6 restoration project,” said Commissioner-in-charge Mingus Mapps. “Seeing the reservoir restored to its picturesque state will be a win for our community and is a testament to both the hard work of Water Bureau staff and Portlanders’ support of this project. Maintaining historic infrastructure isn’t always a quick fix. I am grateful for the work done by Water Bureau staff to prioritize safety, protect the surrounding park, and develop this project in a fiscally responsible way.”

During routine maintenance in 2021, bureau staff discovered voids between the concrete of the reservoir and the ground beneath it. Unsure of the extent of the voids and worried that they might damage the earthen dam that holds the reservoir in place, staff drained the reservoir immediately. Further investigation indicated the voids were less significant than feared. With a few repairs, the voids will no longer pose a structural risk to the dam, allowing the reservoir to be refilled.

“Our team worked hard to find a path toward groundbreaking that keeps costs manageable despite significant local competition for construction labor and supplies,” said Water Bureau Director Gabriel Solmer. “We are committed to safe stewardship of this historic infrastructure the community will enjoy for years to come.”

“The Water Bureau is as excited as the community to refill Reservoir 6,” said Chief Engineer Jodie Inman, who leads the stabilization project. The bureau decided to conduct reservoir repairs in-house after a thorough procurement process showed it was the best way to manage the City’s costs.

Crews will spend the first week of the project excavating the reservoir’s liner to access and fill the voids. Then a new layer of concrete will be poured to support the weight of a filled reservoir. Construction is expected to conclude in winter 2023–2024.

“We appreciate the support of City Council in providing funding for the required repairs,” Inman said. “Once the funds became available on July 1, we finalized the design and worked with contractors on a construction plan that prioritized delivering the project within available funds. Ultimately, we found our own Maintenance and Construction team was best for the job.”