Urban Runoff in San Diego

urban-runoff-san-diegoUrban runoff is the single biggest threat to water quality in San Diego.1

Urban runoff is water that flows over man-made surfaces in densely populated areas and drains directly into our water bodies. Stormwater, irrigation and other water absorb the materials on top of the surfaces including pollutants such as oil, grease, pesticides, metals, bacteria and viruses and toxic chemicals.

And then washes it all into our rivers, bays, lakes and ocean.

In Southern California, storm drains carry millions of gallons of polluted runoff to the ocean everyday. In San Diego, all public storm drains directly link to our beaches without any wastewater treatment.


Photo Credit Marco Gonzalez

Urban runoff creates negative impacts such as these:

  • Human illnesses have been clearly linked to recreational use of coastal waters near storm drains.
  • Urban runoff pollutants build up in the tissues of fish and other aquatic animals, which people eventually eat.

1 Southern California. 2000. KC Schiff, MJ Allen, EY Zeng, SM Bay. Marine Pollution Bulletin 41:76-93.