Council approves award for wastewater digester boiler replacement

On Feb. 18, the Sunnyside City Council voted to award a construction contract to replace a failing digester boiler at the city wastewater treatment plant.

The council approved a resolution authorizing the city manager to accept the bid results and execute documents awarding Schedule 1 of the digester heating system upgrade to SCI Industry Services, LLC for $332,174. The motion was made by Councilor Whitley and seconded by Councilor Foster; the council voted in favor and the motion passed.

City staff told the council the existing boiler has been in service since the mid-1990s, has required repeated repairs over the last three years and has been leaking. Raul Sanchez, city staff, said the new boiler has already been ordered and the contract covers removing the old unit and installing the replacement. "The digester is a piece of equipment out there that needs to constantly keep the sludge at a certain temperature for the microorganisms to work properly," Sanchez said, describing the boiler’s role in maintaining treatment conditions that allow sludge to be converted to biosolids.

Council members asked whether the work had been budgeted and how the project would be funded. Staff said the design work and equipment purchase were started in 2024 and that construction will be paid from the sewer fund. The city reported four bids were received; the $332,174 award was the lowest.

Staff did not give a completion date at the meeting. Council members were told the old boiler will remain in operation until the new unit is installed and the contractor performs a short switch-over intended to avoid significant disruption to treatment operations.

The council approved the resolution on the motion from Councilor Whitley and second from Councilor Foster.