First study of surfer health during wet and dry weather shows water quality and illness correlation

October 27 2016

The Surfrider Foundation announced the results of the first-of-its-kind study of surfer health during both wet and dry conditions, developed in collaboration with scientists at Southern California Coastal Water Research Project (SCCWRP); University of California, Berkeley, School of Public Health; and Soller Environmental. The Surfer Health Study (SHS) was designed to quantify the health risks of untreated urban runoff onto public beaches and examine the relationship between water quality and a range of reported health outcomes.

The study monitored health effects of surfers during the winters of 2013-2014 and 2014-2015 at two San Diego, California-area beaches, Ocean Beach and Tourmaline Surfing Park, that are very popular for year-round surfing. The San Diego River discharges to the ocean at the north end of Ocean Beach and the Tourmaline Creek/Storm Drain discharges to the ocean near the primary surfing area at Tourmaline Surfing Park in Pacific Beach.

Ocean water samples were collected and analyzed daily during the study period. Notable findings from the study included: 

  • There was a statistically significant correlation between water quality (as measured by fecal indicator bacteria (FIB) enterococcus and other FIB) and illness rates during wet weather.  In other words, the higher the fecal indicator bacteria concentrations, the higher the chance of illness.
  • Norovirus was detected in 96% of the samples from San Diego River and 72% of the samples from Tourmaline Creek during rain events. Possible causes of this include integrity problems with the sewer system, sewer/storm drain cross-connections, or impacts from homeless populations.
  • The “72 hour rule” (stay out of the water for 72 hours after a rain event) was validated by the study. Illness rates were highest when surfing during rain and the first day after the rain. Illness rates decreased with each day following rain, declining to near baseline levels after 3 days.

As a result of the study, local, regional and state policy managers will evaluate whether it is appropriate to make any changes in beach water quality standards or public health notifications. The City of San Diego and other entities are conducting investigations in the San Diego Creek and Tourmaline Creek watersheds to try to identify and eliminate sources of fecal pollution.

The Surfrider Foundation will continue to be involved in these policy discussions and investigations to work towards improved water quality and public health protection.


About Surfrider Foundation

The Surfrider Foundation is a non-profit grassroots organization dedicated to the protection and enjoyment of our world’s oceans, waves and beaches through a powerful activist network. Founded in 1984 by a handful of visionary surfers in Malibu, California, the Surfrider Foundation now maintains over 500,000 supporters, activists and members, with more than 80 volunteer-led chapters and 60 clubs in the U.S., and more than 350 victories protecting our coasts. Learn more at