Flooding not expected as Allegheny River ice thaws

Flooding is not anticipated along the Allegheny River as ice that formed during the recent record-setting cold snap begins to melt, a National Weather Service meteorologist said Tuesday.

After setting a record low of 5 degrees below zero Friday, the high Wednesday is forecast to rise into the 40s, meteorologist Shannon Hefferan said.

Ice has been confirmed at the usual Allegheny River “hot spots” in the Armstrong County communities of East Brady and Templeton.

Ice coverage is more extensive on the Allegheny north of Lock 5 near Freeport, where it is up to 2 inches thick, according to John Dilla, chief of locks and dams with the Pittsburgh district of the Army Corps of Engineers.

The ice is not affecting navigation, Dilla said. Towboats are able to push through that level of thickness.

Ice is reported to be 3 to 4 inches thick farther north at Lock and Dam 9 near Templeton, but it is not a concern for navigation because there is no traffic north of Lock 6 in the winter, according to the Corps of Engineers.

The weather service has been asking the public for more reports and photos of the ice.

While rain is expected Friday into Saturday, Hefferan said the ice should flush through before then.

“Hopefully, everything just gradually melts and goes downstream,” she said.

Further lessening the concern for flooding: There is not much of a snow pack, the rivers are not very high and only about a half-inch of rain is expected.

But Hefferan cautioned that it’s difficult to predict how ice will move.

Ice jams occur when chunks of ice clump together and block the flow of the river. Unlike open-water floods, ice jams can take less water to produce significant impacts and can be sudden and difficult to anticipate.

While there are known trouble spots, such as Bradys Bend and Oil City, jams can happen anywhere.