Following heavy rains throughout the Upper Allegheny River Basin, the Allegheny Reservoir is several feet above its usual summer pool level.
The U.S. Army Corps of Engineers is unloading that water.
As a result, the river downstream is running fast and high.
The Corps prohibits vehicles at the tailwater access when the outflow is 6,000 cubic feet per second or higher. On Thursday and Friday, the discharge was more than three times that level - 18,900 cfs.
And the high flow is expected to continue.
"Significant increases in outflow from Kinzua Dam are planned for the next several days," according to the Corps. "As a result it is expected that the river will be flowing at or near bank full conditions."
Residents and visitors hoping to fish on the river this holiday weekend may be disappointed.
"Boaters and anglers are advised to exercise caution while these high flows are being maintained," a Corps message said.
"These high flows are essential in order to release flood storage caused by recent heavy runoff in the upper river basin," according to the Corps. "The reservoir level must be lowered to maintain adequate storage space for possible future floods."