Clean Up Stonington Harbors will present results from tests of water from 10 sites on the Mystic and Pawcatuck rivers at its annual meeting at 7:30 p.m. Thursday at the LaGrua Center in Stonington.
An influx of volunteers in 2009 allowed for the testing to be expanded.
Tests on samples from Wequetequock and Pequotsepos coves showed fecal coliform levels from May through September exceeded the levels for safe shellfish consumption, according to Claire Galvin, water testing director.
August samples of enterococci were two to six times over the safe swimming level, she added.
CUSH President Gracelyn Guyol said with more data, the group will be able to pinpoint where the pollution is coming from and suggest corrective actions.
For information about becoming a volunteer water tester, contact Galvin at (860) 535-3978.
Complete test results will be available Thursday at: www.cushinc.org.