Iowa DNR will keep two bacteria measures for recreational waters

Public opposition to the proposed rules change factored into the reversal

The lake at F.W. Kent Park in Oxford, Iowa, on Monday, Sept. 15, 2014. (Jim Slosiarek/The Gazette)
The lake at F.W. Kent Park in Oxford, Iowa, on Monday, Sept. 15, 2014. (Jim Slosiarek/The Gazette)

The Iowa Department of Natural Resources plans to keep two methods of measuring bacteria in recreational waters after a public outcry about ditching a second measurement.

“The department has decided to drop the proposed removal of the single sample maximum from the state’s water quality standards,” Roger Bruner, supervisor of the DNR’s water quality assessment section, said in an email to The Gazette Wednesday.

The decision to table the rules change was made, in part, because of public opposition and because the DNR wants to wait until the U.S. Environmental Protection Agency completes a five-year review of water quality criteria, Bruner said.

The DNR tests recreational waters for E. coli — a bacteria that can sicken swimmers — through two criteria.

One is the single sample maximum, which is 235 organisms per 100 milliliters of water for primary recreational waters, such as lakes used for swimming, and 2,880 organisms per 100 milliliters for secondary recreation waters.

The second criteria is geometric mean, which is the median level of E. coli in four samples on different days that can’t surpass 126 organisms per 100 milliliters.

If water samples show the geometric mean is too high, or more than 10 percent of samples exceed the single sample maximum, the DNR lists the water body segment on the impaired waters list required by the U.S. Environmental Protection Agency.

The DNR’s water quality assessment division last summer proposed eliminating the single sample maximum, which DNR Water Quality Bureau Chief Jon Tack said in a statement is “overly stringent” and “not an appropriate measure for water quality assessment and permitting purposes.”

The agency held three public hearings in September and accepted online comments.

The majority of community members who spoke at a public hearing Sept. 6 in Washington said they want Iowa to continue to use two ways of measuring bacteria in Iowa’s recreational waters.

“The standard should not be lowered in any way, shape or form,” John Miller, of Fairfield, said.

The Iowa Environmental Council reported Wednesday more than 700 Iowans, including the council, had expressed concerns about the plan.

“The change would have resulted in the removal of 29 lakes and rivers from Iowa’s impaired waters list,” Susan Heathcote, the council’s water program director, said in a prepared statement. “The proposed change also would have eliminated the need for IDNR to identify the cause of the impairment and implement a restoration plan to reduce bacteria pollution so that the water is safe for people to enjoy.”

Bruner said the proposed change would have caused a 3 percent reduction in the list.

“The Iowa DNR still believes, as originally stated, that the single sample maximum is only appropriate for issuing public health warnings at beaches in the State of Iowa,” Bruner said Wednesday.

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