‘Dead zone’ off Louisiana may expand

Share via
From the Associated Press

Researchers predict that the oxygen-depleted “dead zone” that recurs off the Louisiana coast will expand this summer to 8,543 square miles -- its largest area in at least 22 years.

The forecast, released Monday by the Louisiana Universities Marine Consortium, is based on a federal estimate of nitrogen compounds from the Mississippi River watershed that will reach the Gulf of Mexico. It discounts any effect storms might have.

The dead zone near the Mississippi River delta is one of the largest areas of oxygen-depleted, or hypoxic, coastal waters in the world. Hypoxia can result from farm fertilizers, erosion and treated sewage, according to the U.S. Geological Survey.


Algae feed on the pollutants, and when the algae die, the decay consumes oxygen faster than it can be brought from the surface.

As a result, marine life may die if it doesn’t move, the consortium website says.