The main channel of the Lower Mississippi River runs 950 miles from its confluence with the Ohio River, through parts of seven states and to the river’s mouth at the Gulf of Mexico. Water quality in this reach of the river is influenced by land use and water management in the 1.2-milllion-square mile Mississippi River watershed, which covers about 40% of the continental United States. The LMRCC’s geographic area of interest focuses on the lower river reach and what remains of the river’s active floodplain. Millions of people rely on this reach for drinking water, agricultural and industrial water use, tourism, and outdoor recreation.
Available information indicates that the river is cleaner than it used to be. Limited long-term data, available only from the lowest parts of the river, suggest that the river is a lot cleaner than it was before implementation of the 1972 federal Clean Water Act and federal clean air legislation – and the resulting requirements for treatment of municipal and industrial waste. Louisiana State University Professor R. Eugene Turner compiled water quality monitoring records from 1901 to 2019 from four locations along the river in Louisiana. His research, published in early 2021, found the concentrations of certain pollutants, such as bacteria and lead, have decreased dramatically, while dissolved oxygen has increased and the river’s pH has improved.
However, as a new water quality data inventory, commissioned by the LMRCC, concludes, “The limited data are such that it is impossible to achieve a full picture of water quality and ecosystem health in the Lower Mississippi River. … A comprehensive physical, chemical, and biological monitoring program is needed to better understand and assess the health of the river.” The study’s authors said the LMRCC is well-positioned to convene stakeholders and plan and implement a more comprehensive water quality monitoring program on the Lower Mississippi River.
The new report updates and expands upon a 2014 water quality data inventory, also commissioned by the LMRCC.
“A comprehensive physical, chemical, and biological monitoring program is needed to better understand and assess the health of the river.”
Water Quality Data Inventory of the Mainstem Lower Mississippi River,
National Great Rivers Research and Education Center, 2021