Development Planning Program

Standard Urban Storm Water Plan (SUSMP)

Requirements for Developments/New Developments

General Requirements


•  Municipalities in Los Angeles County are required to reduce pollutant discharges from certain types of development/redevelopment projects. The City is required to evaluate the projects listed below for assignment of specific design standards and installation of post-construction infiltration or mechanical treatment controls.

•  Single-family hillside homes that disturb 1 acre or more of soil by grading, clearing, and/or excavating

•  Housing developments (including single family homes, multifamily homes, condominiums, and apartments)

•  Industrial/commercial facilities, which necessitate the disturbance of 43,560 square feet of soil by grading, clearing, and/or excavating

•  Automotive service facilities (SIC codes 5013, 5014, 5541, 7532-7534, and 7536-7539)

•  Retail gasoline outlets (SIC code 5812)

•  Stand alone restaurants

•  Impervious parking lots designed to create 5,000 square feet/25 or more parking spaces located outdoors on an impervious surface, from which runoff has the opportunity to enter the MS4

•  Any project, including those that are not listed in the above categories that is located in or discharges directly to an environmentally sensitive area (ESA) causes storm water runoff that is likely to impact a biological species or habitat and includes the creation of 2,500 square feet of impervious area.