Historic bridge survey update
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Historic bridge survey update

Texas historic bridges

Lohmans Crossing Bridge

Did you know that TxDOT inspects over 55,000 bridges across the state? When bridges need to be repaired or replaced, TxDOT must assess the historical significance of the bridge before approving the project.

Bridges aren't just important for engineering. They tell stories about:

  • National trends in transportation, such as building bridges to separate roadway and railway crossings.
  • The development of cities.
  • Shaping the identity of communities.

Since there are so many bridges in Texas, TxDOT evaluates them by dividing them into groups. TxDOT’s latest update re-assesses the historical significance of the state’s “non-truss” bridges constructed before 1946.

Survey status

TxDOT's Non-Truss Bridge (NTB) update is underway. To date, TxDOT has: 

  • Written a Historic Context about the construction and use of these bridges in Texas with an accompanying Visual Glossary to illustrate some of the bridge terms used in the context.

  • Established a process to evaluate the historical significance of the most common types of bridges built before 1945. This process follows the National Register of Historic Places requirements. This methodology also established which bridges require additional research and closer study. This methodology is available upon request by email.

Based on these documents, there are now approximately 1,300 non-truss bridges left to study. TxDOT needs your help to determine if there are designs, unique histories, or other information that would make these remaining non-truss bridges special. 

Interactive Comment Map

  • View the location of the 1,300 bridges planned for further research.
  • Provide information or history about the bridges.
  • Read the National Register of Historic Places eligibility evaluation for the bridges studied to date.
View the map and share feedback

What is a truss bridge?

Truss bridges use a structural framework of triangles joined together to carry heavy loads. With a single exception in Texas, truss bridges are both metal and constructed in a variety of designs.

US 190 truss bridge over the Colorado River
The 1940 bridge carrying US 190 over the Colorado River in Lampasas County is an example of a truss bridge.

What is a non-truss bridge?

Non-truss bridges do not use a truss frame. They come in a variety of shapes (arches, beams, and slabs), materials, and sizes. Between 1905 and 1955, many Texas road designers used these types of bridges. 

US 79 Mustang Creek
The 1939 bridge carrying US 79 over Mustang Creek in Williamson County is an example of a non-truss bridge.
White Oak Bayou Bridge photo, black-and-white

Questions or Comments?

Contact Rebekah Dobrasko, Project Manager, Cultural Resources Section Director at 512-431-3422 or by email.