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Re-awakening the Dead Zone in the Gulf of Mexico

The entire population that lives upriver has a huge impact on what happens at the mouth and beyond. As the Mississippi empties into the Gulf of Mexico, the pollution it carries is creating a dead zone in the Gulf that is growing each year.

The reason this is called a dead zone is that the water cannot support aquatic life because an excess of algae blooms is using up the oxygen. Aquatic life needs at least 5 parts per million of oxygen to survive. The dead zone is below 2 parts per million -- a condition called hypoxia. Pollution from undefined sources, such as rainwater and snowmelt washing over the lands and carrying fertilizers and pesticides, carry these pollutants into the water and down to the Gulf of Mexico.

One big factor that made this Dead Zone is what we have been outing on our lawns. Phosphorus creates algae in the water. Up until recently lawn fertilizers were high in phosphorous. There are many good ways to keep your lawn healthy without using these harmful chemicals. When soils and plants are healthy, plants naturally resist disease and pests -- allowing gardeners and lawn owners to reduce (or avoid) the use of pesticides and quick-release fertilizers. Healthy lawn and garden practices were developed by professionals familiar with excellent horticulture practices, and they often save homeowners time and effort in the long-run and promote a beautiful landscape. (

One example of helping the river is that in 2005 Minnesota passed a law stating that homeowners cannot use fertilizer containing phosphorus.. Minnesota soils are naturally high in phosphorus, so the lawns there usually don't need any extra. You can tell the amount of phosphorous on a bag of fertilizer: look for the middle number on a bag of fertilizer. It should be zero.



One River Mississippi

















Minneapolis / St. Paul : Environmental Issues

June 24