Elevated levels of E. coli have been found at Avocado Lake Swim Beach in Fresno County, according to the Fresno County Department of Public Health. Officials say the Central Valley Regional Water Quality Control Board recollected a sample on Aug. 22 that recorded an E. coli concentration of 1553.1 MPN/100 ml, which surpasses the Statewide Bacteria Water Quality Objectives established by the California State Water Resources Control Board. E. coli is a bacteria bound in the intestines of warm-blooded animals and serves as an indicator of fecal pollution in water. Officials say that although most E. coli is harmless, it is essential to be cautious when levels exceed the recommended safety threshold due to the high risk of illness for swimmers and others who interact with the water.