People regularly come in contact with water with pollutants and have no symptoms of illness, Cheryl Eversole, Dallas County Health Department Administrator said.
Eversole responded to a July 25 article in which a resident stated swimming in the Niangua caused a skin wound infection and an illness. The resident submitted a drinking water sample in which E. coli and coliform were found.
“Thousands of residents and visitors enjoy our local waterways without incident each year,” Eversole said.
The Missouri Department of Natural Resources outlines water quality standards in the Clean Water Commission’s Water Quality publication. It states allowable limits to various pollutants in bodies of water, including E. coli.
The Niangua River from Bennett Springs to Lake of the Ozarks is not listed as “impaired” by the Department of Natural Resources interactive map of listed waters. Fifty-six miles of the upstream Niangua are impaired by E. coli, however. Also in Dallas County, nearly 44 miles of the Little Niangua are impaired by dissolved oxygen.
Lake of the Ozarks, downstream from Bennett Springs and Lead Mine Conservation Area, is not impaired by water pollutants. There is a notable span of river without test sites from the Niangua River at U.S. 64 near Bennett Spring to the Lake Niangua Dam in southern Camden County.
Also published by the Department of Natural Resources, the Clean Water Commission published a Jan. 4, 2018, list of impaired waters as a table. E. coli was the most common pollutant, which affected 34 percent of impaired waters. The second most common pollutant was dissolved oxygen, at 15 percent of impaired waters.
Over 42 percent of pollutants come from an unknown source or a “nonpoint” source across a large geographic area.
The local health department tests well water samples and sometimes find E. coli and coliform are present.
“The majority of residents drinking the water have no symptoms,” Eversole said. “People with an immune disorder or chronic illness are more susceptible to illness of any type.”
Eversole also said the Missouri Department of Conservation has no part in water testing or reporting.
The interactive map of listed waters can be found at https://ogi.oa.mo.gov/DNR/tmdl_imprdwater/index.html?BUSINESSID=51735.