Chesapeake Bay Hypoxic Zone (“Dead Zone”) Update for August 2016

On August 17, 2016, the Maryland Department of Natural Resources (Md. DNR) reported that the dissolved oxygen conditions in the Chesapeake Bay were average in early August 2016, compared to records from 1985 to 2015.  The so-called “dead zone” in the Bay—that is, the area of “hypoxia,” where the levels are below 2 milligrams per liter (mg/l) of water, too low to support the Bay’s normal community of organisms—covered about 1.15 cubic miles (about 14 percent of the Bay’s mainstem area), compared to the 1985-2015 average of 1.13 cubic miles for early August.  In addition, no areas were found to be “anoxic”—that is, with dissolved oxygen levels below 0.2 mg/l—and no such areas have been found since 2014.  In July 2016, the Bay’s hypoxic area had covered 1.65 cubic miles, about 20 percent of the Bay mainstem and the seventh largest area recorded in July during the 1985-2015 period.  In June 2016, federal and state Bay scientists had predicted that the maximum 2016 dead zone would be about 1.58 cubic miles.

Sources:
Maryland DNR, “2016 Chesapeake Bay Hypoxia Report—Early August Update,” online (as PDF) at http://dnr.maryland.gov/waters/bay/Documents/HypoxiaReports/2016_earlyAugust.pdf.

Bay “dead zone” average in early August, Bay Journal, 8/17/16.

For a previous Water Central News Grouper post on this year’s dead zone, please see Chesapeake Bay “Dead Zone” Prediction for 2016, Plus Link to Univ. of Md.’s “EcoCheck” Web Site with Previous Predictions and Links to “Report Card” Conditions Reports, posted 6/15/16.