Stormwater to Sewer Diversion and Reuse Project at Ocho Rios Way (CI 5600)

The objective of this project is to design and engineer a stormwater diversion system within the Ventura County portion of the Upper Malibu Creek Watershed to divert the dry weather stormwater flow to the nearby downstream sewer system. The diverted flow will be conveyed to the Tapia Water Reclamation Facility (TWRF) for treatment. TWRF is under joint ownership by the Las Virgenes Municipal Water District (LVMWD) and the Triunfo Water and Sanitation District (TWSD) through the Las Virgenes - Triunfo Joint Powers Authority.

The Malibu Creek Watershed encompasses a geographically delineated area emanating from the Santa Monica Mountains, containing portions under the jurisdiction of the County of Ventura (County), the City of Thousand Oaks (City), Los Angeles County and several privately owned areas. Total Maximum Daily Loads (TMDLs) for bacteria, adopted by the Los Angeles Regional Water Quality Control Board (RWQCB) in 2006, and nutrients, approved by the US Environmental Protection Agency in 2003, assign water quality limits for the City, County, and other responsible parties. These regulations mandate lowering bacteria and nutrient concentrations. These limits are described within the Municipal Separate Storm Sewer System Permit (MS4 permit), adopted in September of 2021. One option to meet these requirements is to divert the dry weather stormwater flows to the downstream sewer system.