Walnut Lane Memorial Bridge (Philadelphia, Pennsylvania)

The Walnut Lane Memorial Bridge is a prestressed concrete girder bridge in Philadelphia, Pennsylvania, designed by Gustave Magnel of Belgium and built by the City of Philadelphia. Completed and fully opened to traffic by 1950, this three-span bridge carries Walnut Lane over Lincoln Drive and Monoshone Creek. It was the first major prestressed concrete beam bridge designed and built in the United States when completed. It was also the longest open spandrel arch bridge of its time (233 feet).

The form of the bridge is simple and appears to be like many highway bridges carrying traffic on US highways. The bridge deck is supported by thirteen concrete girders, each spanning 160 feet. These girders were prestressed by post-tensioning four wire cables embedded in the concrete. Although this type of construction had been used in Europe for quite some time, the Walnut Lane Memorial Bridge was innovative in the United States and led to the successful application of this technology in this country. The material-saving bridge cost about $700,000 to construct—about 30 percent cheaper than a regular concrete arch design.

Note: This is a different bridge than the nearby Walnut Lane Bridge (1908).

Adapted from William H. Shank, "Historic Bridges of Pennsylvania", revised ed. (York, PA: American Canal & Transportation Center, 1980), at 3-4, and from other sources.