A. Installation of a Temporary By-pass Pump station • Temporary by-pass pump(s) shall be fully automatic in operation with variable speed (Variable Frequency drives) to provide flow rate (pump capacity) meeting varying demands. Contractor shall be responsible for 24/7 pump uninterrupted operations. • Existing soft start and VFDs shall be used for temporary pumps power and controls. . • Pump suction and discharge connections, pipe work, associated valves and appurtenances will be specified and provided by the contractor based on Design Consultants specifications. B. Construction of a 12 x 10x 12’ Flow Meter (Effluent) Vault o The Effluent Flow Meter is the priority of construction due to State Water Recourses Control Board (SWRCB) regulation and water loss audits that are mandated; o Per design and guidance of the geotechnical report; o May involve relocating of underground utilities; o Need to install new insertion flowmeter as specified by the design installed via a hot tap; o Run new underground power and signal conduits to vault; o Pull new power and signal wires to vault; o Programming new flowmeter signals to existing Allen Bradley PLC; o Update SCADA screens and historian for new flowmeter information C. Construction of a new 90’ x 16’ wide structural vault of depth 25’ to house the existing high service manifold. The design includes an alternate design to repair and/or replace the existing manifold. o The intent of the vault is to provide operations with a clear view and access to the mechanical assembly(s) of its HSPS housing 16 pumps and 24” butterfly valves. This approach will help operations and contractors perform maintenance, and replacement of critical infrastructure related to the operation of the station i.e. 24” butterfly valves and associated parts. For functionality, the vault is expected to be open and meet standard access, security and safety requirements, including lighting, a stairway, a guard rail, and a sump and process drain to remove ground water. o Per design and guidance of the geotechnical report o Will involve relocating of underground utilities o Repairs to existing pump pad aprons, additional shoring due to soil erosion o Repair(s) to pump cans associated with some of the existing pumps o Additionally, a prefabricated valve vault at the East end of the HS vault to include an isolation valve o Repair or replace valves as needed o Repair or replace existing pump as needed
