Site work and new construction of a water / sewer project in Antioch, California. Completed plans call for site work for a water / sewer project.

Bids may only be submitted by District-prequalified General Contractors. The Electrical Subcontractor listed in the bid shall also be District-prequalified. See Article 3 of Section 00 21 13, Instructions to Bidders, for the Final Prequalified Contractors List. The Work includes but is not limited to construction of three (3) new aeration basins, one (1) new secondary clarifier, two (2) new pumping stations for return activated sludge (RAS) and surface waste activated sludge (SWAS), and associated above and below-grade process piping; installation of new aeration blowers, rotary drum thickeners, and hydrocyclones; modifications to the Primary Effluent Pumping Station (existing Tower Trickling Filter Pumping Station), including the installation of new pumps; modifications to the existing Sanitary Drain Pumping Station; installation of new sodium hypochlorite metering pumps and new hydrocyclone pumps, and one (1) new polymer pump; surface and site improvements including modified parking areas, grading, paving and drainage; modifications to existing site utilities including but not limited to sewer, water, and gas; construction of a new electrical building and installation of two (2) new MCCs; construction of a new standby generator and fuel tank as well as the construction of new electrical duct banks to support the new process facilities; the demolition of existing Aeration Basin 5, the Tower Trickling Filters, and Tower Trickling Filter odor control system (biofilter); and all other additional work as needed to construct a complete project as specified in the Contract Documents. Question Deadline 07/24/2026 at 5:00 PM PT Online Q&A Inquiries regarding further information about the Project may be directed to Sean Williams, Project Manager at seanw@deltadiablo.com.