The California Regional Water Quality Control Board, Los Angeles Region adopted the Los Angeles County Municipal Separate Storm Sewer System Permit (LA County MS4 Permit) on November 8, 2012, which was subsequently amended on September 8, 2016 (Order No. R4-2012-0175-A01). The permit requires that each city improve the quality of water that enters stormwater collection systems, in an effort to control the amount of pollution to our groundwater basins, creeks, rivers and the ocean.

As was required under the previous stormwater permit, this amended version requires that 84 cities within the Los Angeles County inspect businesses with certain Standard Identification Classification (SIC) codes to ensure that they are complying with requirements and that the appropriate Best Management Practices (BMPs) are being implemented. 

 Inspection Request 

To request an inspection, call City Hall at (626) 333-2211 and an inspector will contact you within 48 hours of your request. Prior to requesting an inspection please have the following information ready: 

  • Business Name 
  • Address 
  • National Pollutant Discharge Elimination (NPDES) Permit Number 
  • SIC Classification 
  • Contact Name 
  • Contact Phone Number
  • Contact E-Mail address