PA Great Outdoors Visitors Bureau
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Friday Facts about the world-famous Nebraska Bridge in Forest County.
For most of the year vehicles cross the Nebraska Bridge near the quaint town of Tionesta without incident. The 187-foot-long structure over Tionesta Creek functions like many other truss bridges in western Pennsylvania, and its everyday appearance doesn’t indicate anything unusual about its existence. It’s a completely ordinary bridge with one exception: For at least few weeks each year, it’s underwater.
Built in 1933, the Nebraska Bridge took its name from the small lumber community of Nebraska that it served. At that point, Tionesta Creek flowed freely to the Allegheny River, and although the waterway swelled and shrank some with seasonal rains and snowmelt, the bridge sat high enough to provide regular access across the creek. Unfortunately, many communities downriver weren’t so fortunate, and intermittent flooding created recurring problems as development increased along the Allegheny’s banks.
To control this flooding, the U.S. Army Corps of Engineers built the
Tionesta Dam during the late 1930s and put it into service in 1940. While its creation would ultimately prevent hundreds of millions of dollars of damage downriver, the residents of Nebraska four miles upstream of the dam had to relocate, as the impounded water would inevitably overtake their homes. However, the Nebraska Bridge stayed in place, and for more than three-quarters of a century now, it has regularly disappeared underwater and emerged again as water levels rise and fall behind the dam.
At normal levels, the water flows close to the underside of the bridge, but kayakers and canoers can sometimes pass safely underneath. A launch site and parking lot at the bridge’s southern end give easy access when the water is low enough, and boaters can continue on to the dam at the western end of Tionesta Lake. When the water is high, paddlers have the unique opportunity to navigate through the upper beams of the bridge and explore a completely different waterscape.
William Koller, bridge engineer for the Pennsylvania Department of Transportation’s northwest region, notes that the Nebraska Bridge is structurally sound, thanks in part to renovations in 1999 and 2011, and regularly inspected for safety.
Learn more and find other interesting places to visit in Pennsylvania’s Great Outdoors region online at
VisitPAGO.com.
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PennDOT via HistoricBridges
"This bridge will soon be the only truss bridge in all of Forest County. This bridge is also noted for annually being flooded well above the deck, making this a "seasonal" crossing to say the least. The flood waters that this bridge receives are due to a nearby dam. As such, the flood waters are not raging floodwaters that carry a truss bridge off its abutments and crush it into scrap metal downstream, but are instead more or less calm and just drown the bridge. Water levels have risen high enough such that the entire bridge was underwater. In one of these cases, after the water level dropped, a bunch of debris that was floating on the water was left on top of the truss." |
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| PennDOT via HistoricBridges |
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