Report finds bacteria in most US lakes

A new analysis by Environment America indicates that bacteria levels reached potentially unsafe thresholds at nearly seven in ten tested water locations.

The organization reviewed data from more than 4,500 river and lake testing sites in 17 states. The findings show that at least one unsafe day was recorded at 69% of these locations. John Rumpler, the group's clean water director and senior attorney, stated that the 'Safe for Swimming' report addresses both consumer and environmental concerns.

Rumpler noted that E. coli, an indicator of fecal matter, was detected in every state included in the study. He explained that while the waters are not contaminated constantly, the issue is widespread. Approximately half of the 4,000-plus monitoring sites recorded elevated E. coli levels on 25% or more of the days they were tested.

The report identifies sewage overflows, stormwater runoff, and leaking septic tanks as primary sources of the contamination. Rumpler argued that government action could reduce the financial burden on local ratepayers. He stated that if the federal government provides more resources, less of the cost falls on local citizens. However, he cautioned that local and state officials should not cite a lack of federal funding as an excuse for inaction.

Environment America has made the results available on an online dashboard that breaks down the data by state. The organization emphasizes that contamination levels can shift daily, requiring public vigilance before swimming.

Officials recommend checking state or county health advisories and the EPA's water quality portal prior to visiting a lake or river. Additional precautions include avoiding water bodies for 48 to 72 hours after heavy rain, a period when sewage overflows and runoff typically peak. Swimmers are also advised to avoid water that appears discolored, smells strong, produces foam, or is located near a discharge pipe.