| Key Facts |
| Bridge Name | Facility Carried / Feature Intersected | Location | Structure Type | Construction Date / Builder or Contractor |
| Davis Avenue Bridge | Davis Avenue Over Woods Run Avenue | Pittsburgh: Allegheny County, Pennsylvania | Metal Pinned Cantilever Deck Truss, Stationary | 1898 By: Fort Pitt Bridge Works of Pittsburgh, Pennsylvania |
| Technical Facts |
| Alteration Date | Structure Length | Main Span Length | Roadway Width | Bridge Width | Main Spans | Approach Spans |
| 1986 | 396 Feet (120.7 Meters) | 156 Feet (47.55 Meters) | 20.3 Feet (6.2 Meters) | 36.3 Feet (11 Meters) | 1 | 5 Steel Stringer |
This bridge is an extremely unusual structure. It is an old and relatively small arch-shaped example of a pin-connected cantilever deck truss bridge. As such, it is significant for this unusual and early design. It has been altered when many members and parts of the bottom chord were incased in unsightly modern plate steel. However, the original parts appear to remain under this plate steel, suggesting that a properly-executed restoration that would restore this bridge, perhaps for pedestrian use, might be able to remove these and bring the bridge back to its original level of integrity and beauty. Pittsburgh, the "City of Bridges" would do well to consider the full restoration of this rather unusual example of bridge technology that was fabricated by a prominent local company that was prolific on a national scale.
The Pennsylvania Historic Bridge Inventory gives this bridge an unfair review, because it fails to acknowledge that many of the alterations could be removed as part of a restoration, which would increase the historic integrity of the structure. Given the unusual, pin-connected cantilever design and lattice floor beams, this bridge should be considered historic, despite the alterations. The Historic Bridges of Michigan and Elsewhere HSR rating correctly reflects this fact. The Historic Bridge Inventory's non-historic finding is only further discredited by the fact that the Historic American Engineering Record documented the bridge. One might suspect that perhaps HAER documented the bridge prior to alteration, but this was not the case. Either way, it seems morally wrong to reward cities that damage the integrity of their historic bridges through insensitive alteration by delisting a bridge from a historic bridge list, which then frees said city from any barriers to further alteration or demolition. Certainly, alterations are something to consider when weighing the feasibility of restoration and the value of a particular structure in a comparative study. However, in the case of Davis Avenue, the structure itself is sufficiently rare, and the alterations also appear removable, thus, the bridge should still be considered historic.
Information and Findings From Pennsylvania's Historic Bridge InventoryDiscussion of Bridge The 399' long, pin-connected, 5 span, Pratt deck truss bridge has short stringer spans between the main span and approach spans that correspond in shape to the topography of the ravine the bridge crosses. The bridge has uncommon detailing to some of its members, like the lattice web floor beams, but it was altered in 1986 when it was strengthened. Half of the lower chords were strengthened by additional material encasing the original, and 8 of the built up verticals were strengthened. The cantilevered sidewalks are finished with handsome, wrought iron railings. Although a long bridge, within the local context, which is noted for its handsome and innovative, late-19th century arch and truss bridges, it is not historically or technologically significant. It has been altered, and it has no innovative details. The deck truss was a common bridge type for ravine crossings throughout the last quarter of the 19th century. Discussion of Surrounding Area The Davis Avenue Bridge carries a 2 lane city street and 2 sidewalks over a 2 lane city street in a residential area of Pittsburgh's north side near Riverview Park. The houses in the hollow date to mid- and late-19th century, but they are highly altered. Brighton Heights, the neighborhood at the deck level, is later, but it is not distinguished, and there are is later infill housing. The areas do not have the integrity or architectural significance to be a historic district. Bridge Considered Historic By Survey: No |
