Research Area: Rapid Indicators

Though California’s beach monitoring programs are the most extensive in the nation, current laboratory measurement methods used to enumerate indicator bacteria (multiple tube fermentation, membrane filtration and chromogenic substrate) require an 18- to 96-hour incubation period, which is too slow to keep pace with changes in bacterial indicator levels in the environment. Recent studies have shown that 70% of contaminated beaches are clean 24 hours later. Thus, contaminated beaches remain open during the incubation period, but may already have returned to acceptable levels by the time laboratory results are available and warning signs are posted. This incubation time lag also makes it difficult to track sources of microbiological contamination.

SCCWRP Research

SCCWRP has been assisting the State Water Resources Control Board (SWRCB) with development of new molecular methods to detect bacteria by:

• Holding workshops to alert researchers and others about the application of these technologies to beach water quality monitoring
• Administering a competitive Request for Proposals to fund researchers capable of developing new measurement methods
• Assisting method developers in the development process; and
• Conducting independent testing to evaluate whether the new methods produce results equivalent to existing methods.

While SCCWRP’s efforts have been successful thus far, none of the methodologies are quite yet ready for implementation. Several have shown great promise, but each has shown some deviation in results from existing methods for at least some samples. These methods will require refinement and subsequent testing. SCCWRP will conduct the next set of activities necessary to bring new rapid methods into regular use.

Rapid indicator research projects include:

For more information about rapid indicator research, contact John Griffith at johng@sccwrp.org (714) 755-3228.

This page was last updated on: 03/31/2009