Mississippi saltwater incursion threatens farms, can exacerbate nutrient pollution.
A prolonged Midwest drought is reducing the flow of fresh water in the Mississippi River. The infiltrating salt threatens drinking water, but also the ability of farmers to grow crops in affected areas, according to a water quality monitoring expert and environmental economist at Cornell University. In addition, the unwelcome saltwater can cause more nutrient pollution.
Catherine Kling is an environmental economist and a faculty director at the Cornell Atkinson Center for Sustainability. Kling also served for 10 years on EPA's Science Advisory Board.
Kling says:
"At a certain point, groundwater and soils become too salty to grow crops and marshes become the only viable land use. Additionally, some of these marshes and wetlands can become too salty to effectively clean waters, resulting in more nutrient pollution, harmful algal blooms etc.
"Another problem that arises when saltwater intrudes on cropland is that saltwater interacts with fertilizers that are present in the soils and releases them, causing more pollution.
"Unless we take substantive steps to address these problems, stories of drinking water being compromised by saltwater, Harmful Algal Blooms (HABs), Nitrate pollution, and other growing sources of contamination will almost surely become increasingly common."
Source: https://www.cornell.edu/