Environmental groups in Ohio and Michigan sued the U.S. Environmental Protection Agency on Tuesday, accusing it of dragging its feet on protecting Lake Erie from harmful algae that have fouled drinking water supplies in recent years.
The federal lawsuit said the agency's lack of action is delaying steps that could combat the algae blooms in the shallowest of the Great Lakes.
The sometimes toxic algae are a threat to both drinking water and wildlife and have become more prevalent in recent years.
Blooms in the western end of the lake blanket its waters and turn the lake into unsightly shades of green in most summers. An outbreak in 2014 contaminated the tap water for more than 400,000 people around Toledo.
Groups including the National Wildlife Federation want the EPA to make a decision on whether the western part of the lake in Ohio and Michigan should be declared an impaired watershed.
Such a move would allow for increased pollution regulations.
Michigan last year proposed designating its portion of Lake Erie as impaired, but Ohio resisted doing the same for its entire section and instead wants only some shoreline areas on the impairment list.
The lawsuit said the EPA has failed to act on the proposals within 30 days as required under the Clean Water Act.
A message seeking comment was left with the EPA on Tuesday.
The agency in December said it was reviewing both proposed impaired-waters lists. It also said that if Ohio's proposal is rejected because it determines the state's entire share of Lake Erie is impaired, the EPA would then propose adding those waters to the list.
Groups including the Lake Erie Charter Boat Association and the Michigan United Conservation Clubs warned the EPA it planned to file a lawsuit in December, but they noted on Tuesday that no action has taken place on the proposals.
"Continuing to kick the can down the road will only make the problem worse for Lake Erie, our environment and our economy," said Mike Shriberg, Great Lakes regional executive director of the National Wildlife Federation.
While steps have been taken to reduce the farm fertilizer runoff and municipal sewage overflows that feed the algae, environmental groups and some political leaders have become frustrated by the pace and depth of those efforts.
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