Gulf Dead Zone Estimated To Be Size of Southwest Ohio

Des Moines Register:

U.S. scientists are expecting an average "dead zone" in the Gulf of Mexico in 2014 that will cover an area about the size of the state of Connecticut.
The forecast, developed by researchers at the University of Michigan, Louisiana State University, and the U.S. Geological Survey, among others, said the dead zone, located off of Louisiana and Texas, is expected to reach a size of between 4,633 and 5,708 square miles.
The zone is caused by nutrient runoff, primarily from human activities such as wastewater and fertilizer used in agriculture to grow crops. The runoff stimulates an oversupply of algae that consumes most of the life-giving oxygen supply in the water, driving away sea life.
The largest dead zone on record was 8,480 square miles in 2002.
"We are making progress at reducing the pollution in our nation's waters that leads to 'dead zones,' but there is more work that needs to be done," said Kathryn Sullivan, undersecretary of commerce for oceans and atmosphere and an administrator at the National Oceanic and Atmospheric Administration.

For reference, 10 counties in southwestern Ohio, stretching from Hamilton and Clermont County to Shelby and Mercer County, totals 4531 square miles.  That's a pretty big anoxic zone.