Researchers predict smaller Chesapeake Bay dead zones

June 29, 2021 GMT

Researchers say the Chesapeake Bay likely will have a smaller than average oxygen dead zone this summer.

The Daily Press reported Tuesday that this looks to be second year in row when the bay’s areas of low or no oxygen are lower than recent averages.

A computer model predicts that low-oxygen waters will be 14% below the average of the last 35 years. The area of no oxygen will be 18% below average.

One explanation is that river flows into the bay are smaller than average because of lower rainfall in the first several months of the year. But another reason is efforts to reduce the amounts of nitrogen, phosphorous and sediment that those rivers carry from farms and cities into the bay.

Nitrogen and phosphorous feed the algae blooms that consume oxygen in the water. Sediment clouds water and kills off the aquatic plants that feed oxygen into the bay.


Beth McGee, the Chesapeake Bay Foundation’s director of science and agricultural policy, cautioned that large portions of the bay still won’t have enough oxygen to support a healthy ecosystem.

Researchers focused on dead zone research are from the Chesapeake Bay Program, the University of Maryland Center for Environmental Science, University of Michigan and U.S. Geological Survey.