Tualatin council approves $230,000 change order for hydro turbine installation; project total rises to $920,000

The Tualatin City Council on Feb. 24 adopted Resolution 5870-25, approving a $230,000 change order to a previously approved contract for an in-pipe hydro turbine installation. The added work raises the contract total to $920,000 and relocates the bulk of electrical infrastructure to a fenced, centralized location on city property.

The project captures energy that is now dissipated at a pressure-reducing valve in the city’s water system and converts it into electricity. Staff said the revised alignment will increase flexibility for future uses — including potential on-site backup power, battery storage and EV charging — and improve site security.

Key facts and figures: The original construction contract approved in June 2024 was about $690,000. City staff reported they have secured about $575,000 in external funding so far; with the proposed change order the city’s net out-of-pocket cost is now expected to be about $65,000, with a projected payback period of approximately 4.4 years. When the project was first presented to council, staff had estimated a maximum city contribution of $214,000 and a roughly seven-year payback; staff said higher-than-expected outside funding reduced the city’s share.

Staff presentation: A staff member identified as Nick (staff member) said the project is at 60% design and described the benefits of a centralized equipment location behind the site's B Building — nearer the diesel generator and solar array — which he said would allow better integration with potential future batteries or expanded renewable generation. He told council the larger alignment requires more underground trenching but offers increased operational flexibility and security.

Council debate and vote: Councilor Brooks asked about additional future uses and whether the city had talked with nearby battery manufacturers. Nick said staff had discussed battery programs with Portland General Electric and were watching evolving utility incentive programs. Councilor Gonzales voiced concern about the frequency and scale of change orders on city projects and said the added cost gave him pause; he voted against the resolution. Council President Pratt and other council members supported the change, saying modest additional spending now could avoid under-building for future needs. The roll-call vote was 6 in favor, 1 opposed; Councilor Gonzales voted no.

Implementation: The resolution authorizes the change order so staff can finish the remaining design and begin construction. Staff said if the council had not approved the change order, the original alignment would proceed under the previously approved contract. Public-utility coordination — including final terms for net metering and possible future programs for distributed battery storage — remains under negotiation with Portland General Electric and state regulators.