The beginning of 2023 brought torrential downpours to the West Coast, causing devastating flooding, mudslides, and power outages. Across the country, we’ve watched drought-stricken California, in particular, get slammed with a bomb cyclone that eroded beaches and hillsides, destroyed homes and businesses, and turned roads into rushing rivers. This bomb cyclone was part of a series of ‘atmospheric rivers’ that drenched the state. The situation in California has been dire, with some areas requiring full evacuations due to anticipated flooding risks. Now, California residents are working to rebuild and clean up the mess that the storms left behind. In areas where Surfrider’s Blue Water Task Force volunteers have been able to access local beaches and their water sampling locations safely, they are being met with exhaustive amounts of trash and microplastics, as well as abnormally high levels of bacteria.

Extreme weather events, especially slow moving and large coastal storms, not only cause severe flooding that puts public safety and property at risk, but they also generate large amounts of urban runoff that pollutes our beaches. What’s worse, stormwater can easily overwhelm wastewater infrastructure like septic systems and sewers, causing raw sewage to be discharged into coastal waters. Sewage and polluted runoff can contain bacteria, viruses, and other contaminants that can make people sick. In California, surfers and other coastal users are well acquainted with the “72 hour rule”, which is used to advise people to stay out of the water after it rains. Surfrider recommends that people always heed swim and sewage advisories to protect their health. This will only become more important as our coastal communities continue to experience the impacts of climate change. Research predicts that climate change will cause future atmospheric rivers to become 25% longer, 25% wider, and dump even more water as they pass over land.

Since the January rains began, many of our chapter-run Blue Water Task Force (BWTF) programs along the central coast of California have measured extremely high bacteria levels in the water, showing evidence of the storm-related pollution events. In San Mateo County, each of the Chapter's six sampling sites measured high bacteria levels that exceed the state health bacteria standard.  Likewise, the San Luis Obispo (SLO) Chapter measured extremely high bacteria levels at nearly every site they tested from Avila Pier to Pismo Beach. On January 5th, Pismo Beach had a bacteria concentration of 1,274 MPN/100mL, which is the highest this site has tested in the last 2 years, and is well above the state water quality criteria of 104 MPN/100mL for safe recreation. Further north, samples collected next to the Avila Pier and in San Luis Obispo Creek were even higher, reaching upwards of 17,000 MPN/100mL. It's not extraordinary or atypical for the SLO Chapter to measure high bacteria levels at many of their sites; however, this storm event resulted in  bacteria concentrations that are higher than any measured by the chapter over the past two years. The Chapter has been actively advising people to avoid entering the ocean for the last two weeks.

Read the full article about bacteria left after a cyclone by Michelle Parker-Ortiz at Surfrider Foundation.