National Weather Service United States Department of Commerce

The Major River Flood in Pittsburgh and surrounding areas
January 19-21, 1996

 

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Flooding along RT 65 near I-79 bridge along Ohio River.

 

Major to near record flooding occurred January 19-21, 1996 over the entire Upper Ohio River Basin, due to widespread rains and runoff from snow melt in the mountains of the Allegheny Plateau. Movement and jamming of ice on the rivers and streams increased the magnitude of this flooding.

River flooding occurred on the Allegheny, Clarion, Conemaugh, Monongahela, Cheat, Youghiogheny and the Upper Ohio River. Runoff estimates from the snow melt on January 18 (as temperatures rose into the sixties) and the rainfall that fell on January 19 were between 2.50 and 3.00 inches over the two-day period across much of the area. In some mountainous areas, runoff was estimated as high as 4.50 inches in a 24-hour period. These totals exceed the normal precipitation amount for the entire month of January.

 

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Flooding...downtown Pittsburgh.

 

The flooding on the Allegheny River was compounded by a wave of water from an ice jam that broke near Parker, PA. Ice jamming also contributed to what was near record flooding along the Clarion River, a tributary of the Allegheny River. Near record flooding also occurred upstream of the Conemaugh Reservoir on the Conemaugh River, another tributary to the Allegheny River.

Major flooding occurred along the main stem of the Monongahela River in southwest Pennsylvania. Two tributaries of the Monongahela River, the Cheat and the Youghiogheny Rivers, rose rapidly when 15 to 25 inches of snow cover throughout the West Virginia and Maryland Mountains quickly (less than 24 hours) melted.

 

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Flooding across RT 65 (Ohio River Boulevard) in the borough of Emsworth.

 

The Ohio River forms at Pittsburgh, PA at the confluence of the Allegheny and Monongahela Rivers. The magnitude of the flood at Pittsburgh, the nation's largest inland port, was amplified by the fact that the crests of the Monongahela and the Allegheny Rivers reached Pittsburgh at about the same time. Normally the Monongahela River crests about 4 to 8 hours before the Allegheny River. Downstream of Pittsburgh, near record flooding levels approached the levels recorded in June 1972 produced by the remnants of Hurricane Agnes.

No deaths occurred in this flood event! Only a few minor, indirect injuries (e.g., minor back injuries while filling sand bags) were reported. However, the property damage was enormous.

 

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Flooding along the Allegheny River. Note bypass on right covered with water and ice.

 

In western Pennsylvania, approximately $31 million in damages were reported to houses, businesses, personal property, public facilities, roads and bridges. Allegheny, Armstrong, Beaver, Butler, Fayette, Indiana, Washington, and Westmoreland counties had damages exceeding $1 million.

 

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Flooding along Allegheny River. Note underpass on left full of ice and water

 

In east central Ohio, approximately $4 million in damages occurred. Belmont and Jefferson counties suffered the most damages. Damage estimates for these two counties alone totaled approximately $3.2 million.

In Northern West Virginia, approximately $10.0 million in damages were reported.

In Garrett county, Maryland, approximately $3.0 million in damages occurred.

Estimates of the total flood-related damages for NWSFO Pittsburgh's Hydrological Service Area which includes the Allegheny, Monongahela, and the Upper Ohio (to Hannibal, OH) River Basins were approximately $48 million.

 

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Photo taken from 6th St Bridge along Allegheny River.