First Flush

First Flush is an annual volunteer monitoring event that samples storm drain runoff during the first significant rainfall of the wet season. During the first rain water washes significant amounts of pollution off street surfaces, driveways, and curbs and into storm drains. This concentrated mix of often polluted water flows directly from these storm drains into creeks, rivers and the Monterey Bay.

At each storm drain water samples are collected and sent to a professional lab to assess levels of non-point source pollutants such as nutrients (nitrate, orthophosphate and urea), metals (copper, lead and zinc), bacteria (total coliform, enterococcus and E.coli), hardness,  and total suspended solids. Additionally, field measurements of water temperature, conductivity, pH, and transparency are taken by volunteers at the monitoring sites.

First Flush results are compared to the Central Coast Ambient Monitoring Program’s (CCAMP) Action Levels. These action levels are not used for regulatory purposes. Rather, they provide guidance on potential impacts to the health of the marine ecosystem. First Flush results illustrate the impact of non-point source pollution generated through our daily interactions in the environment – high metal concentrations can be attributed to car brake linings, high nutrient concentrations can be linked to fertilizers, and high bacteria concentrations are generated by failing sewer and septic lines, wildlife and pet waste.

To get involved, please complete this volunteer application, give us call at: 831-464-9200 or contact us via email at: djchirco@coastalws.org.