The sampling of 13 upper Lake of the Ozark coves Tuesday found none with E. coli levels in excess of the federal standard for public swimming beaches, the Missouri Department of Natural Resources announced today. In the final year of a five-year program, the department is sampling water from coves in the Upper Lake of the Ozarks from the Brown Bend area (Mile Marker 61) to the U.S. Highway 65 bridge (Mile Marker 90). The purpose of the program is to develop a five-year baseline that will assist in future studies of the lake’s health. While most strains of E. coli are harmless, some can cause gastrointestinal illness. These bacteria and other pathogens can reach lake water from many different sources, both human and animal.