Approved by the Transportation Policy Committee on February 13, 2018
Approved by the Public Policy Committee on May 6, 2018
Adopted by the Board of Direction on July 13, 2018
For the continued safety of America's traveling public, the American Society of Civil Engineers (ASCE) advocates that a bridge safety program for both public and private bridges be fully funded and consistently operated to rehabilitate or replace structurally deficient bridges and to properly maintain all others. This program should preserve full functionality of all bridges to support the safe, reliable, and efficient operation of existing transportation systems, and to allow these systems to be utilized to their full capacity. Such programs as a minimum should include:
- Regular inspection and evaluation programs that incorporate state-of-the-art investigative and analytical techniques, especially of older bridges which were not designed and constructed to current design, loading, and geometric standards;
- Posting of weight and speed limits on structurally deficient and/or functionally obsolete structures;
- Implementing and adequately funding regular, system-wide maintenance programs that are cost-effective means of ensuring the safety and structural adequacy of existing bridges; and
- Utilizing a comprehensive program for prioritizing and adequately funding the replacement of functionally obsolete and structurally deficient bridges.
Structurally deficient bridges may either be closed, or weight restricted due to deteriorating structural components. While not necessarily unsafe, these bridges must have limits imposed for speed and weight. A functionally obsolete bridge has older design features and, while it is not unsafe for all vehicles, cannot safely accommodate current traffic volumes, and vehicle sizes and weights. These restrictions not only contribute to traffic congestion, but also affect safe and efficient personal mobility and movement of goods and services. The restrictions may also result in such major inconveniences as school buses taking lengthy detours and increased response times for emergency vehicles required to use alternate routes. Additionally, such deficiencies may adversely affect the performance of transportation systems during or in response to emergencies or disasters.
Continued neglect will ultimately result in higher annual life-cycle costs of bridges due to shortened service life. Therefore, investments in maintenance and repair to improve the condition and functionality of the nation's bridges will reduce required investment in the future. The average age of the nation's bridges is 43 years, which leaves just seven years until a typical 50-year design life is exceeded.
With funding made available from the American Recovery and Reinvestment Act and Fixing America's Surface Transportation (FAST) Act and its preceding transportation funding bills, there has been some improvement in the condition and performance of the transportation infrastructure. As of 2017, 54,259 of the nation's 612,677 bridges, or 8.8%, were structurally deficient, as compared to 9.1% of all bridges in 2016. However, despite this improvement, functionally obsolete or structurally deficient bridges on the nation's transportation systems continue to pose significant potential hazards which may jeopardize safe, reliable, and efficient operation.
The most recent estimate puts the rehabilitation project backlog for the nation's bridges at $123 billion (2017 dollars). Total bridge expenditure by all levels of government for capital outlays (including system preservation and system expansion) was at $12.8 billion in 2013. Additional funding beyond that level will therefore be needed to continue to reduce the backlog of structurally deficient bridges and prevent more bridges from becoming structurally deficient.
The safety, functionality, and structural adequacy of bridges are key components necessary to support and ensure the safe, reliable and efficient operation of transportation infrastructure and systems which provide mobility of people and the movement of goods and services. This policy establishes the minimum bridge safety program components necessary for both public and private bridges to ensure an adequate and economical program for the inspection, evaluation, maintenance, rehabilitation, and replacement of our nation's bridges.
ASCE Policy Statement 208
First Approved in 1977