Did you know that the first significant rainfall of the year is called a “first flush”?
During this first rainfall, water washes significant levels of pollution off of street surfaces, driveways and curbs straight into storm drains that empty into local rivers, creeks and streams. Over the past 10 years, Coastal Watershed Council in partnership with local municipalities has been studying the urban pollutants that are being washed into storms drains and local waters.
First Flush monitoring 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.
Residents and business owners can take action before the first flush and other rain events to reduce the amount of pollution being carried downstream. Here is how:
- Remove dead leaves, debris and trash from your gutter, your driveway, your yard, or the street and dispose of them properly.
- Get your sewer lateral inspected: Ensure that there are no major cracks that allow for sewage to seep out and into the groundwater. An inspection can also ensure that rainwater seeping into the ground cannot infiltrate your pipe and back it up.
- Pick up pet waste in your yard: Rainwater acts as a conduit for bacteria to move to nearby creeks and streams or seep into the groundwater.
- Do not apply fertilizers before a rain event.
- Properly store or dispose of fertilizers, paints or chemicals. Do not dump chemicals down gutter. Storm drains are for rain water only.
- Move downspouts so they flow rain water onto grassy or planted areas rather than hard surfaces.



Read the results of past First Flush water quality monitoring events in the reports below. To see a full list of CWC water quality reports, visit our Resources page today.
- 2016 City of Capitola Report
- 2015 City of Capitola Report
- 2014 City of Capitola Report
- 2013 Cities of Santa Cruz & Capitola Report Card
- 2012 Cities of Santa Cruz & Capitola Report Card
- 2011 City of Capitola Report
- 2011 City of Santa Cruz Report
- 2010 City of Santa Cruz Report
- 2010 City of Capitola Report
- 2009 City of Santa Cruz Report
- 2009 City of Capitola Urban Watch & First Flush Report
- 2009 & 2010 County of Santa Cruz Report
- 2008 Report
- 2007 Report
- 2006 Report
- 2005 Report
- 2004 Report
- 2003 Report
- 2001 Report
- 2000 Report