The proposed Pressure Relief Valve Replacement Project (Project) involves the replacement of a pressure relief valve that was previously removed from the existing vault and slip lining the discharge piping from the vault to the discharge outside the roadway right-of-way. The existing steel pipe to be slip lined would be accessed via a manhole in Avenida Pico and from the drainage channel on the downstream end. As part of the construction process, and to determine the location and layout of the buried pipeline, the contractor will string out the new HDPE plastic pipeline across existing grouted rock riprap in the drainage channel bank near the existing outlet. The HDPE pipe will be fed through the existing outlet through and pulled from within the existing vault with cable and winch. The Project does not involve any modifications to the drainage channel. The existing outlet would be temporarily sealed to prevent any construction debris from entering the drainage channel. All construction would occur within the existing channel improvements associated with the vault and armored drainage channel and no new excavation or earth disturbance would be required.