Digester Nos. 1 and 3 Rehabilitation

Delta Diablo Sanitation District is requesting bids on rehabilitation of Digesters Nos. 1 and 3 at its wastewater treatment plant in Antioch, California under Project No. 25116, with bids due November 10, 2026 at 2:00 p.m. PDT and a pre-bid meeting scheduled for October 22, 2026 at 10:00 a.m. PDT. The project is subject to a Project Labor Agreement as outlined in Appendix A of the contract documents.

The scope includes digester cleaning, concrete and coating repairs, replacement of process equipment, piping, valves, instrumentation, sludge sampling and heat exchange systems, installation of variable frequency drives, drainage improvements, exterior coating repairs, bird netting replacement, and associated testing and commissioning. Work is performed at the Delta Diablo Treatment Plant in Antioch, Contra Costa County, California. The project is structured as a lump sum award with line-item bid responses required in paper format submitted through the PlanetBids Vendor Portal.

Bid bonds of 10 percent and payment and performance bonds of 100 percent each are required. Questions are due November 3, 2026 at 5:00 p.m. PDT through an online Q&A period. No estimated bid value is disclosed. The estimated start date is October 17, 2026; specific project duration will be determined by the awarded contractor. Interested parties should contact Sean Williams at 925-756-1926 or SEANW@DELTADIABLO.ORG for additional information.