The Portland Water Bureau conducted tours of its new covered reservoirs at Kelly Butte Tuesday.
They’ve been designed to withstand a Cascadia Subduction Zone earthquake.
They replace a much smaller tank, built in the 1960s when Oregon’s earthquake risk was not as widely understood.
Water Bureau engineer Teresa Elliott said the work came in about $15 million under budget, because the original estimates were made before the 2008 economic crisis.
“We had planned on a lot higher prices and then we were able in construction to save a lot of money on what we thought we would need for it,” Elliott said.
Concrete and reinforcing steel bars cost significantly less than expected.
Portland is under a federal mandate to cover all its open reservoirs by the end of 2020.
Facilities at Mt. Tabor and Washington Park remain uncovered.