Elkhorn Slough Reserve releases water quality report card

The Elkhorn Slough Research Reserve released its first water quality report card this week and the results are mixed.

Of the 23 stations graded by the report card, none of the sites received an “A”, only six received a “C”, and 12 sites received an “F.”

Generally, the sites with the highest grades are located in the main channel near the mouth of the slough, where the tides circulate freely; sites without good circulation, located behind levees or water control structures, have the lowest grades due to stagnant conditions.

The area receiving the best marks also are where the most abundant and diverse wildlife in the estuary is found.

“We’re publishing this report card to increase community awareness of water quality issues and to engage neighbors, visitors, local businesses, and agencies in improving the health of the Elkhorn Slough,” said Reserve Water Quality Specialist John Haskins.

Researchers take regular water quality measurements and samples at 23 stations around the slough, which are analyzed for nine attributes—including temperature and pH, as well as turbidity (the amount of particulate matter suspended in the water), nutrients (nitrates and ammonia, which can foster excessive algae growth), and dissolved oxygen levels (which need to remain high to support fish and other animal life in the water).

To view the report card in English or Spanish, click here. Copies also will be distributed at the Reserve’s Visitor Center and at local businesses, such as kayak shops.