Folsom works on master plan to ditch sewer spills

City officials are hiring a consultant to prepare a $400,000 Folsom wastewater master plan to avoid sewer spills like the one at Folsom Lake last year. The city updated the Folsom sewer collection system evaluation in 2017, also known as the Capacity Assurance and Capital Plan, or SECAP. The update included a significant expansion of the earlier hydraulic model to include 252 miles of Folsom sewer lines. The city of Folsom currently supplies treated and untreated water to public and private users with more than 25,000 connections. Folsom uses a model of a standard six-hour, 10-year storm to evaluate pump and pipeline capacity. A 10-year storm isn't once every decade, but rather a storm that has a 10-percent chance of happening any given year. For example, an El Dorado Hills Irrigation District sewer pipe leaked into Folsom Lake at Brown's Ravine last year off Green Valley Road, just outside the Folsom city limits. The raw sewage also flooded into the gated Rolling Hills Estates in El Dorado County. "It was brown with stuff floating in it and it was bunching up into certain driveways," resident David Michael said on television. SECAP is meant to prevent sewer spills by finding problems, such as areas with high inflow and infiltration. Steps are then taken to establish repair projects. The state updated waste discharge rules in 2023, requiring Folsom to update the SECAP and develop a Sanitary Sewer Master Plan. Only one proposal came in, but city officials said the bidder, Water Works Engineers LLC, is an ideal candidate. Water Works is familiar with relevant sewer planning for clients across the West, including Roseville and El Dorado. Water Works has also designed multiple sewer projects north and south of Highway 50 in Folsom, staff said. The Folsom City Council was scheduled to review the $399,938 master plan contract Tuesday evening.