Water quality in nine of San Diego County’s watersheds is worsening because of the ongoing drought, according to results of testing released by San Diego Coastkeeper.
Nearly 200 Coastkeeper volunteers conducted monthly water quality testing in 2014. Samples were analyzed for basic chemistry, nutrients and bacteria.
The drought has likely led to low levels of oxygen that is dissolved in water, a condition found in 30 percent of the samples, Coastkeeper Program Director Travis Pritchard said. Low levels of dissolved oxygen can be fatal to aquatic life, he said.
High levels of bacteria were found in 57 percent of the samples, which is a concern because the watersheds flow into the ocean, Pritchard said. Waterways always carry a certain amount of bacteria caused by natural sources, “but the levels in our data are so high, we have major concerns,” he said.
According to Pritchard, eight of the nine tested watersheds had unhealthy levels of E coli.
He said it’s possible the drought has created shallow, slow-moving and warm streams in the region that serve as bacterial breeding grounds. Some of the usual testing sites dried up last year, he said.
The San Luis Rey, Carlsbad, San Dieguito and Los Penasquitos watersheds in the North County received scores that landed them in the “fair” category, according to Coastkeeper.
Thewatershed near the international border was rated “poor.”
“Sadly, none of our watersheds scored higher than fair this year, so we have work to do to improve water quality in San Diego County,” Pritchard said. “Our data also illustrates something that we’ve always known, and can now show with science — all aspects of a watershed’s ecosystem are connected and changes ripple throughout.”
According to the report, the Los Penasquitos and San Diego water quality went down from “good” in 2013, while Carlsbad improved from “marginal.”
San Diego County is home to 11 watersheds, and Coastkeeper conducts testing at nine of them.
—City News Service
