State Issues New Bacteria Tracking Protocol

bacteria in seawater

Staff scientist Amanda Griesbach says new guidelines will make it easier to fix troubled beaches.

As a water quality scientist, I get a lot of questions about local beach water quality, sources of pollution, and public health risks. Sometimes, providing a definitive answer can be tough. There are a lot of variables when it comes to figuring out what’s going on at a particular site -- location, time of year, and the type of beach (enclosed, open ocean or stormdrain impacted). When you factor in random bacteria distribution in a given location, the science behind beach water quality may not seem so black and white.

Under state law, weekly monitoring is required between April 1 and October 31 for all coastal beaches adjacent to a flowing stormdrain (or known point source) that receive 50,000 or more annual visitors.  The weekly results from a single 100 mL sample of beach water (about the size of a small cup of coffee) are used to make and inform important public health decisions. But challenges loom when analyzing that sample for harmful bacteria and taking corrective action.

For example, current testing methods fail to differentiate among various fecal sources, such as bird, dog or human. Obviously, the first priority is just establishing that there are bacteria in the water. But if we want to abate harmful micro-organisms, we need to know specifically where they are coming from.

And we’re also trying to get more rapid forms of testing. Right now, it takes about 18-24 hours to process a sample. Rapid methods now being developed would give us a snapshot of a particular beach as soon as 4-6 hours, which would be more protective of public health. But it could be years before these new methods are incorporated into state and/or federal beach monitoring standards.

Heal the Bay has always been proactive when it comes to improving beach water quality, and thankfully the State Water Board has supported improving California’s coastal beach water quality through its Clean Beaches Initiative Grant Program.

The Board launched the CBI Grant Program in 2001 in response to the poor water quality and significant exceedances of fecal indicator bacteria along coastal beaches. A Clean Beach Task Force was convened with experts from local agencies, environmental groups, academia, government, and scientific organizations to assist the Board in reviewing beach water improvement project proposals, evaluating their success, and identifying critical beach water quality research needs.

As a member of the task force, I have often found it challenging to decide which water quality improvement efforts are most appropriate and/or effective at a certain beach. The decision becomes even more trying when source identification efforts, protocols, and priorities are inconsistent from beach to beach, from county agency to county agency.

Luckily, the project selection process may be easier in the future, as the State Board recently released a new manual that spells out a clear protocol for tracking bacterial pollution at troubled beaches across the state.

The new set of guidelines – called The California Microbial Source Identification Manual:  A Tiered Approach to Identifying Fecal Pollution Sources to Beaches – is based on the collaborative research efforts of the Southern California Coastal Water Research Project (SCCWRP), Stanford University, UCLA, UCSB and Virginia Tech.

The manual will assist beach managers in identifying sources of fecal bacteria through a step-by-step protocol. The process starts with identifying more obvious potential sources (e.g. large bird population due to uncovered trash bins), as it guides the user through more complex source tracking techniques, including the investigation of a potential sewer/septic leak using genetic markers.

The new source identification manual will not only provide consistency for all future source identification studies, but will allow task force members to make more informed decisions about funding  water quality improvement projects. While the manual may be geared towards beach managers and researchers, it contains background information on potential fecal bacteria sources, mitigation efforts and the CBI Program that the general beachgoing public can benefit from.

I commend the State Board and researchers who worked diligently to complete this manual. We’re now one step closer to having a uniform Beach Program, where the benefits of consistent and efficient monitoring will ultimately lead to strengthened coastal public health protection.

The full manual can be found at:  http://www.swrcb.ca.gov/water_issues/programs/beaches/cbi_projects/docs/sipp_manual.pdf