Kelly Butte Reservoir Takes Shape
Over the past 18 months, crews have made tremendous progress on construction of the new 25-million-gallon underground reservoir, access roads, overflow basin, and an intricate network of underground piping, multiple vaults and valve structures a top Kelly Butte in Southeast Portland.
This new reservoir replaces a 10-million above-ground reservoir which was built in 1969. The old reservoir was not large enough to meet Portland’s growing water needs, was not seismically sound, and had regular maintenance issues. The new 25-million gallon reservoir, which will be out of sight under a grassy field surrounded by oak trees upon completion, will be built to current seismic code and will provide adequate water to meet Portland’s needs for generations to come.
Crews are now working to strategically pour the reservoir’s floor, walls, and supporting columns. Several valve structures (valves are pipe connection locations) recently constructed on-site will control the water flow to and from the reservoir.
In tandem, crews are installing a 23-foot wide by 40-foot long valve in a vault under the westbound lane in the 9700 block of SE Powell Boulevard. The new valve is a critical step in connecting the new reservoir to the existing water supply conduit. The prefabricated concrete vault will house large, complex piping and device assemblies.