CLARKSTON, Wash. – The Walla Walla District of U.S. Army Corps of Engineers advises the public to not swim in or drink shoreline river water near the Chestnut Recreation Area after routine weekly testing results showed elevated levels of fecal bacteria in shoreline river water.
As a precaution, warning signs will be posted near the Chestnut Recreation Area’s shoreline.
Initial water-testing results received today, August 16, revealed fecal bacteria counts of 512 per each 100 milliliters of sample. That figure exceeds the 126 per 100 ml. that is deemed safe for swimming areas by Washington state health officials.
Additional water samples will be taken Monday to be tested again for fecal coliforms that pose a potential hazard to human health. District natural resource management officials routinely sample shoreline river water at the Chestnut Recreation Area, even though there is no requirement to do so in recreation areas that don’t feature a designated swim beach.
"For health and safety reasons, we are urging people not to swim or play in the water at Chestnut. The shoreline will not be physically blocked, however, signs are being posted indicating that it is not safe to swim in the area," said Lower Granite Natural Resource Manager Connie Grant.
The Corps’ warning signs will remain in place until future tests show that fecal bacteria levels do not exceed state and federal levels considered safe for people. Boating and fishing in nearby areas remain unaffected, however, fish caught in waters near the swim beach should be thoroughly cleaned and fully cooked before eating.
“This fecal bacteria contamination in shoreline waters likely developed because of waterfowl feces, combined with recent higher seasonal temperatures,” Grant explained. “We will sample again next Monday and the beach will be closed until we can get a good water sample.”
For additional information, call the Corps' Lower Granite Natural Resources Management Office in Clarkston, Wash., at 509-751-0240.