Site work for a water / sewer project in Anderson, California. Completed plans call for site work for a water / sewer project.

furnishing the City of Redding a proposal for Selection of Digester Biogas Conditioning and Combined Heat & Power Generator System at City of Redding Clear Creek Wastewater Treatment Plant per the specifications and general conditions. The cut-off date and time for receiving questions regarding this bid is 5:00 p.m. PT, on Tuesday, July 1, 2025. All inquiries must be made in writing and may be submitted to the email address shown below. Michelle Kempley, Purchasing Officer mkempley@cityofredding.org and Corri Vandiver at cvandiver@cityofredding.org * Event Bid notes: The proposer shall provide the original (unbound), six (6) copies and a USB drive with a PDF copy of the proposal. Electronic submission of proposals will not be allowed. One (1) set of the Fee Proposal is to be submitted in a separate, sealed envelope. The City will award any resulting contract in a manner consistent with the City Purchasing Ordinance. *Site visits will not be conducted. The City can provide photographs of specific areas of the project site as requested by prospective bidders and shared via an addendum. PROCESS DESCRIPTION Pre-processed food waste will be co-digested at CCWWTP along with the plant's biosolids in the plant's existing anaerobic digesters. Food waste slurry will be delivered to CCWWTP from the City's Abernathy Lane Transfer Station and equalized in food waste storage tanks, from which the slurry will be metered into the digesters at a stable constant rate. The plant currently operates two of its three primary digesters (with one held offline for redundancy) in addition to a secondary digester downstream of the primaries that serves as solids and gas equalization and storage. The primary digesters are operated at a mesophilic temperature with sludge heating and recirculation systems. The secondary digester has a floating cover for gas storage. The gas delivery lines from all four digesters tie together into a common manifold, and the secondary digester provides gas storage for the whole system through this manifold. As part of this project, the existing floating cover on the secondary digester will be replaced with a new membrane storage cover with a maximum storage volume of approximately 62,000 cubic feet and a design operating pressure of 9 inches of water column. Existing gas piping will be replaced with larger diameter piping to accommodate the higher gas flows. Co-digestion with food waste will result in a significant increase in biogas production as noted below: o Current range of approximately 40-75 scfm with annual average of 60 scfm @ 60-62% methane o Up to 185 scfm with acceptance of 7,000 tons per year of food waste (Phase 1 of RODEO project) o Up to 235 scfm with acceptance of 10,000 tons per year of food waste (Possible Future Phase 2) The City will utilize conditioned biogas for energy generation in lieu of the current practice of flaring all biogas in excess of what is currently used in the existing digester heating boilers. The CHP Generator system shall include two identical containerized combined heat and power (CHP) generators, each with a 430 - 499 kW power output rating. As part of the Cost Proposal (Compensation Schedule), Manufacturer shall provide pricing for one generator, and additional price for a second generator. The City may decide to delay purchase and installation of the second generator depending on availability of funding for the project and also to pace with the potential ramping up of food waste collection and processing as the project comes online. The Biogas Condition system shall be sized for 250 scfm regardless of whether one or two generators are supplied to the City initially. Complete Construction December 2027