Improving water quality along the Mississippi Gulf Coast
Thursday, February 9th, 2017
Water Quality Blog Series #1
The quality of the water in the Mississippi Sound is a significant indicator of the health of our coastal ecosystems. Improving the water quality that is entering the Mississippi Sound, as well as the coastal bays and estuaries, is a top priority for the state of Mississippi. Therefore the next three blog posts will focus on several aspects of water quality, including different kinds of pollution, water chemistry, and watersheds. This post will focus on pollution and how it can effect water quality in the Mississippi Sound. There are many factors that contribute to decreased water quality in the Mississippi Sound, with nutrient pollution and bacterial contamination listed as the highest priorities for the public.
Water quality is degraded by nutrient pollution, especially excess nitrogen and phosphorus. Sources of nutrient pollution include stormwater, wastewater, animal waste, fertilizer, and certain kinds of soaps and detergents. While nitrogen and phosphorus occur naturally in aquatic ecosystems, a surplus of these nutrients causes plant and algae proliferation. This type of pollution is called eutrophication, and it is primarily caused by pollution due to fertilizer runoff and soil erosion. When these plants and algae die, bacteria and other microorganisms eat the detritus. Hypoxic (oxygen poor) or anoxic (completely depleted of oxygen) habitats can be lethal to fish and other aquatic life, which is why eutrophication is devastating to aquatic ecosystems and the economies of coastal communities that rely on recreational and commercial fisheries.
Water quality degradation can also occur from bacteria in the water. Fecal coliform and enterococci are two types of bacteria that are often present in aquatic environments. These bacteria can enter the aquatic system through direct discharge of waste from mammals and birds, from agricultural and stormwater runoff, and from sewage system failures. The Mississippi Department of Environmental Quality Mississippi Beach Monitoring Program is in charge of issuing water contact Advisories, using Enterococcus sp. as the indicator bacteria. In Mississippi, an advisory is issued because of bacterial exceedance or anticipated bacterial exceedance of a beach action value (BAV) of 104. A closure is issued for a section of beach when there is a known source of pollution, i.e. sewage leaks. All advisories or closures posted can pose an increased risk to human health. The Beach Monitoring Program Task Force has a standing recommendation that swimming not occur during or within 24 hours of a significant rainfall event (1 inch or more) due to the possible influx of bacteria into the system.
Nutrient pollution and bacterial contamination are serious threats to the Mississippi Gulf Coast. A successful Beach Outfalls Challenge could help improve water quality and benefit the ecology of the Mississippi Sound, as well as remedy harm to natural resources harmed by the Deepwater Horizon oil spill. MDEQ is looking for practical, implementable, eco-restoration solutions that will improve water resources. Do you have a great idea? Registration for the Beach Outfalls Challenge is now open! Learn more about the Beach Outfalls Challenge by visiting the ABOUT Page of this website. CLICK HERE to receive periodic updates about the Beach Outfalls Challenge.