Elk River Waste Water Treatment Plant Outfall Repair

The project involves underwater maintenance and repair of the outfall diffuser pipe at the Elk River Wastewater Treatment Plant in Eureka, California, which discharges into Humboldt Bay. The primary work includes replacing 90 degraded neoprene flap-style check valves with 3-inch elastomeric Tideflex check valves to prevent sediment, sand, and shell intrusion into the pipe during low flow conditions. The existing valves have exceeded their useful life and are no longer functional, resulting in accumulated sediment that will be removed during the replacement process. Additional tasks include replacing one nut and restraining bolt on the diffuser pipe and repairing a 6-inch-wide area of spalling using underwater concrete epoxy. All work will be performed by divers using only hand tools at a depth of 10 to 25 feet below Mean Lower Low Water, within a 360-foot section of the outfall located 4,030 feet west of the treatment plant. The project is scheduled for execution during the Summer-Fall 2026 timeframe to avoid disruptions to anadromous fish passage and periods of heavy waterfowl use in Humboldt Bay. The City of Eureka, acting through its Public Works - Engineering Division, is the agency overseeing the work and has classified the project under CEQA categorical exemptions for maintenance of existing facilities and minor alterations, confirming no expansion of capacity or operational change. No formal contract value, solicitation number, or federal acquisition regulation clauses are included in the documentation, and funding details, payment procedures, invoicing systems, and accounting codes are not specified. The point of contact for the project is Henry Baker, Assistant Planner, reachable via email and phone at the City of Eureka’s address on K Street. Technical specifications require functional equivalence of replacement components and compliance with environmental timing constraints, but no ASTM, ANSI, or military standards are cited. No formal contract type, evaluation factors, or bidder certifications are present, and supporting attachments or detailed packaging requirements are not provided, though documentation is on file with the City’s Engineering Division.