| Key Facts |
| Bridge Name | Facility Carried / Feature Intersected | Location | Structure Type | Construction Date / Builder or Contractor | |
|---|---|---|---|---|---|
| ! |
Great Valley Bridge
Greensburg Pike Bridge | Greensburg Pike Over Turtle Creek and Railroad (Norfolk Southern) | Turtle Creek: Allegheny County, Pennsylvania | Metal Riveted Pratt Through Truss, Fixed | 1925 By: Unknown |
| Technical Facts |
| Rehabilitation Date | Main Span Length | Structure Length | Roadway Width | Main Spans | Approach Spans |
| 1978 | 192 Feet (58.5 Meters) | 845 Feet (257.6 Meters) | 24 Feet (7.3 Meters) | 4 | 7 |
This beautiful bridge is an impressive four span through truss with a heavy skew and a notable incline. The skew, incline, and multi-span configuration of this bridge make it stand out as noteworthy. The bridge retains decent historic integrity. Although there are some alterations to the bridge, the overall design and original bridge materials remain intact.
The National Register eligibility of this bridge arises from its association with the historic Pennsylvania Railroad, since this bridge was built with the cooperation of both the county and the railroad to try to eliminate grade crossings on the line.
Historicbridges.org strongly disagrees that the only source of significance for this bridge is the association with the railroad. The bridge should also be considered historically and technologically significant as a relatively complex bridge, since its skew, incline, and multi-span configuration are indicative of a more complicated and noteworthy engineering achievement.
Further, although the bridge was built at the end of its era, the bridge carried the historically significant Lincoln Highway, and indeed the fact that Greensburg Pike was once such a major highway may have been part of the reason why this bridge was built. There was an older bridge that this 1925 bridge replaced however. The Lincoln Highway is significant as the first transcontinental signed highway route and the first national memorial to President Lincoln. Additional local historical information is available here.
Given the wide range of reasons why this bridge is important, its preservation should receive high priority and should come without thinking. However this has not been the case. First, the bridge has not been properly maintained, with the most recent paint project on the bridge dating to 1979, which is 30 years ago! Further, in a poorly designed repair project, the bottom chord was reinforced by pouring concrete in it. This did nothing except to trap moisture and cause further deterioration. Now the concrete is deteriorated and grass is growing in it. Despite the deterioration on the bridge, this structure could certainly still be preserved through a comprehensive rehabilitation project which might well cost less than replacing the bridge. Indeed, the upper portions of the trusses of this bridge in in excellent condition, so it is not like the entire bridge is in need of serious repair. PennDOT is not the only reason why Pennsylvania has one of the poorest records in the nation for historic bridge preservation. Unfortunately, Allegheny County has demonstrated a fair-weather commitment to historic bridge preservation by neglecting the proper maintenance of this bridge and now plotting to demolish and replace this National Register eligible bridge.
Information and Findings From Pennsylvania's Historic Bridge InventoryDiscussion of Bridge The 7 span, 845'-long bridge built in 1925 is composed of 4 rivet connected Pratt thru truss spans (166', 192', 192', 140') and 3 steel deck girder approach spans (52', 52', 42'). The truss spans have built up members of standard steel sections. A cantilevered sidewalk with standard county pipe railing is on the south side. The bridge is supported on concrete abutments, built-up steel bents for the approach spans, and concrete piers for the main spans. Safety shape concrete barriers enclosing the roadway are from a 1978 deck replacement project. The bridge is a late example of its type and design that is not individually distinguished by its technology. The bridge's significance is in association with the development of the PHMC-determined eligible PRR Main Line. It dates from the line's period of significance and it is associated with efforts to improve the safety and efficiency of the line by improving grade crossings. The bridge was built as a joint project of the railroad and the county. Discussion of Surrounding Area The bridge carries a 2 lane road and a sidewalk over a stream, a private access road to the Westinghouse plant, and active Conrail tracks. The setting on the Turtle Creek-North Versailles line is a mix of late 19th to late 20th century commercial and residential buildings. The Conrail line is the former Pennsylvania RR Main Line that has been determined eligible by PHMC (9/14/93). The line is significant for its historic role as an important east-west through route established in the 1850s. The boundaries and period of significance of the line have not been specified by PHMC. Bridge Considered Historic By Survey: Yes |
