Article

by Allison Titus

June 3, 2014—While the vision of a thriving urban riverfront in Santa Cruz slowly comes to life, a new coordinated effort to analyze water quality in the San Lorenzo River is gathering steam. Five different agencies and nonprofits have teamed up for the first time to compile years of water quality testing data and use advanced tracking technology to pinpoint pollution sources on the river—the first step toward eliminating them.

The City of Santa Cruz, the County of Santa Cruz, the Coastal Watershed Council (CWC), Surfrider Foundation and the Regional Water Quality Control Board all routinely test water quality in the river. In October 2013 they came together to form the Water Quality Working Group of the San Lorenzo River Alliance (SLRA), and they’ll be pooling eight different data sets from the last 15 years to analyze the water health of the river. It’s the first time they’ve all shared their information.

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“There has never been this involved of a partnership,” says Greg Pepping, executive director of the CWC.“The fact that this data has been pooled is a huge success.”

Compiling years of test results allows these groups to more accurately track harmful bacteria in the San Lorenzo River. Most of the data collected is on fecal indicator bacteria (FIB), a class of bacteria that live in the gut of warm-blooded animals. Though not all FIB makes people sick, some types, like E. coli, can be very dangerous to people. The Water Quality Working Group is looking specifically for human bacteria, because that is what causes human health problems.

Targeting Pollution in The San Lorenzo River

The three most common sources of human fecal bacteria in waterways are failing sewer laterals (the small pipes running from your toilet to the larger sewage system), septic systems and illegal camping. Sewer lateral failures are hard to monitor and resolve, since they occur largely on private land. Illegal camping is also hard to track, and it’s unknown how big an issue it is. Storm drains are also a huge problem, since they run directly into the river or bay and the water isn’t treated like toilet water is. These are the sources that the Water Quality Working Group is targeting for management.

The challenge is that the FIB data doesn’t specify what kind of gross bacteria is in your water sample. In order to track down the human bacteria, the Water Quality Working Group has begun to utilize microbial source tracking (MST), an expensive but extremely useful type of water testing. The data from this testing tells you whether the FIB in your sample is from humans, birds, dogs, cats, livestock or other wildlife.

“FIB data is useful, but MST is even more helpful,” Pepping says. “FIB data points out bacterial hotspots, but MST zeroes in on the type of bacteria we are looking at.”

The alliance’s pooled resources allow for more consistent use of MST along with FIB testing. The group began using MST testing in April and will continue to test through September. In October, they’ll analyze the results. The MST data will pinpoint hotspots along the river where harmful human bacteria is most abundant.

The health of the river directly affects the health of our local beaches and estuaries.“Surfers are also really involved,” Pepping says. “The Rivermouth is a popular surf break. The water health affects them too.”

Sarah Mansberg, the chair of Santa Cruz Surfrider, which has been testing water at local beaches since 1993, could not agree more.

“We are interested in what is upstream that is causing bacteria down at the beaches,” she says. “Our volunteer Blue Water Task Force tests 20 different beach sites for bacteria, but this alliance allows us to better track sources all the way up the San Lorenzo River.

“We are moving forward,” says Mansberg of the new working group. “We’re not creating assumptions in a vacuum. Together, we are coming up with models of what we think the sources are, and also discussing management practices to bring to the city and county.”

Take Me To The River

Although this sounds like a very messy affair, the situation is not quite as nasty as it seems. “The river is actually cleaner than people think,” Pepping says. “The river is definitely cleaner than its reputation.”

Also, the community is passionate about improving the San Lorenzo’s health. Both Mansberg and Pepping praised the public’s overwhelming support for the SLRA.

“Volunteer data from events such as Snapshot Day is included in the data set, since it is conducted as a scientific study,” Pepping says. “This has been a key part of the project. There is lots of local support, especially because this issue is so challenging. We are dealing with an issue that still stumps even advanced scientists.”

The SLRA has a lot of potential for changing how Santa Cruz manages water quality issues. “There’s not one easy thing to fix, but I am fully ambitious about what we can do as an alliance,” says Pepping. “We hope that the city, county and private landowners can act differently using this data.”