One third of the Chesapeake Bay has "dead zones," according to a new study of the area.|
New research has found low oxygen levels in more than a third of the bay, according to experts at the University of Maryland Center for Environmental Science.
They say the levels are lower than those that are needed to sustain rockfish and other aquatic animals.
The findings were made during a research cruise earlier this month.
The so-called "dead zones" are created when fertilizers and pollutants are washed into waterways, creating algae blooms, which in turn allow bacteria to flourish and consume the oxygen.
Researchers say conditions are about the worst they've been in the 20 years the numbers have been closely monitored.
Delaware, Maryland, New York, Pennsylvania, Virginia, West Virginia and the District of Columbia are in the Chesapeake Bay's 64,000 square-mile watershed.
Those states agreed earlier this year to limit outflows of nitrogen and phosphorous from wastewater treatment plants that drain into the Chesapeake Bay in an effort to reduce such biological "dead zones."