Sewer Planning Support, Hydraulic Model and Master Plan Update
City of Richmond, California

West Yost developed City-wide flow monitoring programs for two consecutive wet weather seasons in order to quantify I/I and provide data for hydraulic model calibration. The master plan was designed to address aggressive deadlines for infiltration and inflow (I/I) and sanitary sewer overflow reduction that are required to meet a settlement agreement with San Francisco Baykeeper. West Yost also developed an innovative flow monitoring program in order to identify and quantify tidally-influenced I/I that collection system operators suspected was occurring. Flow monitors with temperature gauges were installed to coincide with the maximum tide in San Francisco Bay. The result of the study was that more than 1 mgd of I/I was identified, and the failing pipes were fast-tracked for rehabilitation.