InTrans / Aug 14, 2018

Improved Ratings for Covered Bridges through Load Testing, Phase II

According to the Federal Highway Administration (FHWA), approximately 880 historical covered timber bridges remain in the United States. These magnificent bridges were built with several types of heavy timber trusses that were developed during America‰Ûªs first century (1776-1876). These examples of early American bridge building traditions are mostly located in the northeastern United States but are also found in significant numbers in the Pacific Northwest. Pennsylvania, Ohio, Indiana, Vermont, and Oregon have the largest inventories of surviving covered timber bridges. Efforts to preserve the remaining landmark bridges had been driven by a few state initiatives and local fundraising efforts, until federal funds became available through the Transportation Equity Act for the 21st Century (TEA-21) bill that was passed by Congress in 1998. In 1999, FHWA established a National Program for the Historic Preservation of Covered Timber Bridges. The program provides grant funding opportunities for states to protect, restore, preserve, or rehabilitate their historical covered timber bridges. These bridge preservation efforts are guided by the Secretary of Interior‰Ûªs Guidelines for Historic Preservation.