Following a public outcry, the Iowa Department of Natural Resources has abandoned an effort to weaken the state’s E. coli water quality standards. Officials had designed the change with the explicit goal of reducing the number of Iowa waterways deemed impaired.
Environmental advocates had warned public health would suffer if the DNR assessed waterways based on average readings of E. coli levels, rather than the highest single measurement of the bacteria. When the DNR submitted proposed administrative rule changes to the state Environmental Protection Commission this summer, environmentalists were alarmed by a passage in the cover letter from Water Quality Bureau Chief Jon Tack (emphasis added):
The second purpose of this proposed rule is to update the water quality criteria for E. coli by eliminating the existing single sample maximum value. The DNR has determined that the single sample maximum value is overly stringent and is not an appropriate tool for water quality assessment and permitting purposes. The geometric mean E. Coli value will be retained as it is the more appropriate measure and is protective of recreational activity in Iowa’s waters. This change will result in fewer water bodies being listed as impaired by the overly stringent single sample maximum E. coli value. […]
Full article: A rare victory for Iowa water quality