Image courtesy of http://www.cop.noaa.gov/images/GOMhypoxia_map.jpg
The Gulf of Mexico is over 500 miles south of Illinois, but we are very much connected to the Gulf via our rivers and streams. Most of Illinois’ waterways eventually reach the Mississippi River, which drains into the Gulf of Mexico near New Orleans. Therefore, pollution that originates in Illinois eventually winds up polluting the nation’s second longest river and the source of a lot of our seafood.
Pollution from Illinois and other states in the Mississippi River Basin has been linked with an area within the Gulf of Mexico known as the Dead Zone. The Dead Zone forms every summer off the coast of Louisiana, and averages 5,000 square miles. This area is aptly named because oxygen gets so low (<2 mg/L) that ocean life cannot breathe. Species capable of moving large distances can escape the stressful conditions, but less mobile species such as shrimp and crab will perish when dissolved oxygen becomes limiting. Such loss of life is detrimental to the fishing industry and the ocean environment.
Scientists have determined that nitrogen and phosphorus pollution are the leading causes of the Dead Zone. When there are too many nutrients in the ocean, aquatic plants become excessively abundant and deplete the water of oxygen as they decompose. Recent studies by the U.S. Geological Survey have concluded that of all states draining into the Gulf of Mexico, Illinois contributes the most nitrogen and phosphorus pollution. Some of this pollution comes from municipal water treatment plants, but most of it comes from crop and livestock production. Therefore, in order to reduce the size of the Dead Zone, Illinois needs to become a national leader in tackling the amount of polluted runoff reaching the Gulf. The Gulf of Mexico would not be the only beneficiary; Illinois’ rivers would simultaneously become cleaner and safer.
Prairie Rivers Network has joined forces with sister organizations along the Mississippi River to reduce the amount of pollution entering this great river and the Gulf of Mexico. The Mississippi River Water Quality Collaborative consists of 13 environmental and legal partners devoted to clean water and river protection. Our work with the Collaborative includes pushing Illinois to adopt numeric criteria for nitrogen and phosphorus, commenting on wastewater discharge permits, and promoting conservation practices on agricultural lands.