FY 25-26 Catch Basin Retrofit
Under compliance with the Municipal Separate Sewer System (MS4) Permit issued through the National Pollutant Discharge Elimination System (NPDES) program, the City of Walnut is required to implement measures to reduce trash discharged into the storm drain system and downstream waterways. To comply with these requirements, the City must install Full Capture Systems (FCS) within storm drain catch basins located in Priority Land Use (PLU) areas throughout the City. PLUs generally include high-density residential, commercial, industrial, mixed-use, and public transportation areas. A retrofit approach was determined to be the most cost-effective and least disruptive method of achieving compliance, as the devices can be installed within existing infrastructure without requiring reconstruction of the catch basins. Utilizing the existing infrastructure minimizes construction impacts, reduces waste generation, and supports sustainable infrastructure management practices. Work is tentatively scheduled to begin July 6th, 2026.