JEFFERSON CITY — Missouri environmental officials said Thursday that water test results from the Lake of the Ozarks showed high E. coli bacteria at one of 54 sites tested this month.
The bacteria test results are part of a five-year environmental quality study at the lake and were released just two days after the samples were taken. Last year, the Department of Natural Resources took about a month to release similar water test results, which prompted a legislative investigation and changes to how water quality test data are handled.
Tests this year showed high bacteria in Porter Mill Hollow west of the city of Sunrise Beach. Of three samples taken from that cove, only one exceeded the standard for swimming, but another sample there had the second highest E. coli level.
DNR plans to take follow-up samples from the cove this week, and inspectors will check facilities that might drain into the lake. All 54 sites will be tested again in July.
DNR spokesman Judd Slivka said Thursday that E. coli is variable and that the environmental agency is not sure why the test results would vary within the same cove.
The Lake of the Ozarks is about an hour southwest of Jefferson City and draws vacationers from across the Midwest. It was created by a dam owned by St. Louis-based Ameren Corp., which is paying about $15,000 a year to monitor E. coli. The bacteria can cause influenza-like illnesses and even death in people infected through open cuts or ingestion.
E. coli is found in the intestines of warm-blooded animals, and the tests do not identify from where the bacteria originates. It is possible E. coli is coming from livestock and wild animal manure, waterfowl or humans through faulty septic and sewer systems.
The Lake of the Ozarks Watershed Alliance, a group of volunteers with oversight from DNR, takes samples of the lake six times a year during the swimming season. The department also has a separate testing program that checks state beaches for bacteria.
Last year, samples for the five-year water monitoring study were taken May 26, but DNR did not report the results until June 26. Those tests showed high E. coli levels in numerous places and bacterial levels in two places that were 19 times higher than the standard of 126 colonies per 100 milliliters of water.
Later, it was disclosed the department had not properly closed a state park beach at the Lake of the Ozarks, despite results from a separate testing program that showed high bacteria.
A Senate environment committee spent much of the summer investigating how DNR handles water quality testing and recommended a series of changes. Those ideas, such as requiring plumbing codes around large bodies of water like the Lake of the Ozarks, were not approved.
DNR now posts test results on an Internet site with a map illustrating whether beaches are open or closed. The state agency also has changed its procedures so that more people know about high bacteria tests at beaches.