This story was updated to clarify how the EPA would proceed.
The Environmental Protection Agency will propose regulations on nutrient pollution by mid-December 2017 to settle a lawsuit filed by an environmental group in U.S. District Court.
The Missouri Coalition for the Environmentfiled a lawsuit against the EPA in February for not adequately addressing the issue of nutrient pollution through the Clean Water Act. The EPA has agreed to propose rules by next year, unless the agency approves criteria submitted by the state before the deadline.
Nitrogen, phosphorus and other nutrients enter waterways through fertilizer runoff and sewage treatment plant discharges. An overabundance of such nutrients have caused fish kills, harmful algal blooms and dead zones along the Mississippi River.
The EPA generally does not require states to monitor or regulate nutrients in waterways.
"It's an important first step towards thorough protection of our water resources, but there's certainly more to be done," said Alicia Lloyd, clean water policy coordinator at the Missouri Coalition for the Environment.
Lloyd co-authoreda recent report by the Mississippi River Collaborative, a group of environmental policy experts, which noted that many Mississippi-bordering states have not made progress in recent years to develop regulations to reduce nitrogen and phosphorus pollution.
The state last proposed regulations to limit nutrient pollution in 2009, but they were rejected by the EPA.
Missouri Department of Natural Resources spokesperson Tom Bastian wrote in an email that the agency "does not have any additional information at this time."
Follow Eli Chen on Twitter: @StoriesByEli
