The dead zone of the Chesapeake Bay — sometimes covered in red and brown algae and deadly to fish — is shrinking, according to a recent study.
The oxygen-depleted zone stretches from the middle of the bay near Baltimore to around Mobjack Bay near Gloucester County. The latest measure is the 10th smallest in 38 years according to a study by the Maryland Department of Natural Resources and Old Dominion University.
The progress means the bay is getting healthier for aquatic life and safer for humans. Dead zones, which occur when too many algae bloom, can make people sick if they swim in the water. The shrinking dead zone leaves more room for fishing and outdoor recreation.
“The Chesapeake Bay is a critical resource that benefits the Hampton Roads area and it is promising to see this is a little smaller than it was in the past because it shows improvement to the overall health of the bay,” said Joe Wood, senior scientist at the Chesapeake Bay Foundation.
Dead zones occur when pollution, such as fertilizers and dog waste, gets into the bay. Its high levels of nitrogen and phosphorus can cause algae to bloom. When the algae die, they sink and decompose, sucking oxygen from the water faster than plants can replenish it. The vegetation dies and fish and other animals that rely on it will suffocate or have to migrate to an area with more oxygen.
Dead zones expand and contract throughout the year and are linked to spring rainfalls that wash pollutants into waterways. Warmer temperatures can help dead zones grow and last longer.
Virginia and the other states along the bay are working under the Chesapeake Clean Water Blueprint to decrease the pollution. The dead zone has been shrinking as cities have improved the facilities that filter wastewater into the bay. While the commonwealth is on track to reduce pollution from wastewater, it is behind in reducing agricultural and stormwater runoff, according to the CBF.
The blueprint calls for about 90% of the remaining pollution reductions to come from agriculture.
“This year’s results showing a ‘better than average’ dead zone is, in part, a reflection that our pollution reduction efforts are working,” said Beth McGee, director of science and agriculture policy at CBF. “Unfortunately, ‘average’ or ‘better than average’ isn’t acceptable as it means much of the bay is still off-limits for aquatic life.”
The Inflation Reduction Act and the U.S. Department of Agriculture also provided funding this year for farmers to put in forested buffers and wetlands at little to no cost. The buffers trap much of the runoff before it can enter the bay.
Under the reduction act, farmers can get help in using conservation practices such as reducing fertilizers and using no-till or limited-till farming through organizations such as the Environmental Quality Incentives Program.
In a separate report, the CBF is submitting a report to Congress as a guide in allocating funds from the Inflation Reduction Act. The report shows that practices such as adding buffers and incentive programs could save Virginia millions because they reduce the amount of work needed to mitigate pollution.
