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Stormwater Catchment Areas


This GIS layer was created to delineate catchment areas for Municipal Separate Storm Sewer System (MS4) outfalls under the Los Angeles County Flood Control District (LACFCD) jurisdiction pursuant to a 2012 National Pollutant Discharge Elimination System (NPDES) permit.


The data is a compilation of storm drain hydrology studies completed by the LACFCD. To learn more about MS4 outfalls and corresponding stormwater catchment areas, please visit the NPDES site, hosted by the United States Environmental Protection Agency. This project is a work in progress. As more catchment areas are added, this page and GIS data download will be updated.
Stormwater Catchment Areas


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Data Field Descriptions

These areas roughly coincide with Hydrologic Unit Codes (HUCs) as identified by the United States Geological Survey.

Corresponds to a proposed MS4 outfall point identifier.

GIS Source Information
Database Name: n/a
Feature Class Name:
Feature Dataset Name (if applicable):
Reference Date: 2014
Accuracy: Other
Update Frequency: As Needed
Access Constraints:None

Contact Information
Thierno A. Diallo
Associate Civil Engineer
Los Angeles County
Department of Public Works
900 South Fremont Avenue

Alhambra, CA 91803
(626) 458-6920

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