Record-breaking rainfall across the Midwest has washed tons of fertilizer and sewage water along the Mississippi and into the Gulf of Mexico, contributing to a larger polluted area than ever.
Massive 8,000-mile “dead zone” could be one of the gulf’s largest
![Seen from above, the Mississippi River carries sediment into the Gulf of Mexico. That sediment often contains pollutants from fertilizers that cause a spike in algal blooms.](https://i0.wp.com/openrivers.lib.umn.edu/wp-content/uploads/2019/06/Deadzone-Mississippi-River-6-17-2019.jpg?fit=1024%2C768&ssl=1)