10 States Intervene in Mississippi River Nutrient Discharge Lawsuit

Arkansas' Attorney General Dustin McDaniel recently intervened in a lawsuit brought by environmental groups against the EPA regarding agricultural run-off of nutrients like phosphorus and nitrogen in the Mississippi River. The groups, led by the Natural Resources Defense Council, contend that the run-off contributes to hypoxic or "dead" zones in the Gulf of Mexico which are deprived of oxygen and marine life.

McDaniel and nine other state attorney's general filed a motion in the US District Court of Louisiana to intervene in the lawsuit because the plaintiffs are seeking "unnecessary and unreasonable federal regulation of nutrient pollution" in the Mississippi River and its tributaries. Under the suit brought by the environmental advocacy groups, the EPA would force Arkansas and other states in the watershed to institute specific numeric criteria for total nitrogen and phosphorus discharges and impose total maximum daily load (TMDL) requirements within the watershed. McDaniel issued a statement saying that the state was already in compliance with federal requirements from the Clean Water Act and "We do not need more burdensome and costly federal regulation that will threaten important agricultural jobs in the Delta, result in higher sewer bills and negatively impact our overall economy." In addition to Arkansas, the states of Iowa, Kansas, Kentucky, Missouri, Nebraska, North Dakota, Oklahoma and South Dakota joined the motion to intervene in the suit. 

Excessive levels of nitrogen, phosphorus (which is found in fertilizer), and other nutrients can cause harmful algae blooms in the Gulf of Mexico that deplete oxygen for marine life and fish. Last year, the size of the hypoxic zone was estimated by the EPA to be over 6,000 square miles. 

Under the federal Clean Water Act, states may use either “narrative” or “numeric” standards as a method for determining water quality. Many states in the Mississippi River basin use a narrative standard rather than a one-size-fits-all numeric standard to prevent excessive nutrient pollution. Deriving a specific level of nutrients that is allowable in all state waters can be extremely complex, especially because nutrients are essential to life and safe thresholds in aquatic ecosystems vary depending on biological conditions of the water body. 

Agribusiness groups and many municipalities worry about the potential costs associated with a stringent numeric nutrient standard that the court may set - especially for new infrastructure upgrades for water treatment and overall permitting costs. Advocacy groups successfully brought a similar lawsuit against the state of Florida to require the EPA to set new rules for nutrient levels in state waters that could range from $298 to $4.7 billion per year in compliance costs and would increase utility bills between $590 to $990 per year to fund sewer upgrade projects - based on a study by coalition of business groups. The EPA has estimated those impacts to be much lower, but would still range up to $236 million a year in state compliance costs.