Record-breaking water temperatures likely contributed to a fish kill in the
Potomac River near Seneca, where Maryland environmental officials recorded an
extraordinary 94-degree water temperature following days of extreme heat
across the region.
The
Maryland Department of the Environment
(MDE)
confirmed
the fish kill in a social media post, saying, “We’re aware of reports of a
fish kill in the Potomac River near Seneca. Our biologist recorded water
temperatures at a record 94°F. This can trigger a summer turnover event, when
layered warm and cold water suddenly mix and oxygen-poor water rises to the
surface, stressing fish.”
Although the fish kill occurred in
Montgomery County, the Potomac River flows south along the borders of Charles
and St. Mary’s counties before emptying into the Chesapeake Bay, making the
conditions noteworthy for residents, anglers and boaters throughout Southern
Maryland.
The fish kill follows several days of dangerous heat
across Maryland and the Mid-Atlantic. Air temperatures climbed into the upper
90s and low 100s across much of the state, with parts of Montgomery County
reaching about 100 degrees and nearby Washington, D.C., reaching 102 degrees
during the recent heat wave.
...
State officials have not announced how many fish were affected or identified the species involved.
If I'm reading the map right, this fish kill occurred up in the riverine Potomac, above Great Falls. I'm not sure I understand their argument about the summer turnover event. However, it was really hot for a few days there.
