Photo courtesy of TxDOT
Constructed in 1973, the JFK Causeway is the first precast, post-tensioned segmental bridge constructed in the United States.
With 56,313 bridges, the state of Texas has more bridges — small, medium and large — than any other state and due to meticulous inspection and routine maintenance, the structures rank third-best in the nation, according to the American Road and Transportation Builders Association report of state's bridge conditions.
Photo courtesy of TxDOT
"TxDOT has been a leader in innovation and steel and concrete bridge design," said TxDOT's Adam Hammons. "One of the early examples that highlights TxDOT's innovation is the JFK Causeway in the Corpus District. Constructed in 1973, the JFK Causeway is the first precast, post-tensioned segmental bridge constructed in the United States. TxDOT's bridge design policy is documented in the TxDOT Bridge Design Manual. TxDOT's innovation and design policy is put to practice through our array of more than 800 bridge standards that help ensure uniformity in design and construction of bridges across Texas."
The DOT has honed bridge inspections to an artform.
"TxDOT has been inspecting bridges in Texas for nearly 50 years," said Hammons. "All public-use bridges in the state which carry vehicular traffic undergo periodic inspections in accordance with the National Bridge Inspection Standards. With some exceptions, due to structure type or condition, most bridges receive a routine safety inspections every 24 months. The Texas Bridge Safety Inspection Program is managed by TxDOT's Bridge Division. Bridge safety inspections are performed by TxDOT staff and consultant inspectors that meet the training, experience and education requirements of the National Bridge Inspection Standards."
Local Bridge Repairs
The ARTBA's section for Texas in the National Bridge Inventory is fact filled and explains the state's efforts in detail.
The section points out that the state has identified needed repairs on 11,091 bridges.
"This compares to 11,814 bridges that needed work in 2019," it stated. "Over the life of the IIJA, Texas will receive a total of $576.8 million in bridge formula funds, which will help make needed repairs. Texas currently has access to $230.7 million of that total and has committed $178.8 million towards 88 projects as of June 2023. Of the 56,313 bridges in the state, 708, or 1.3 percent, are classified as structurally deficient. This means one of the key elements is in poor or worse condition. This is down from 725 bridges classified as structurally deficient in 2019. The deck area of structurally deficient bridges accounts for 1.2 percent of total deck area on all structures."
The top seven of most traveled structurally deficient bridges in Texas are:
- IH 35E over Oak Lawn Ave & Turtle Creek bridge in Dallas County that was built in 1959. It is an urban interstate where 194,462 vehicles cross it daily;
- IH 610 over FM 521 & BNSF RR bridge in Harris County that was built in 1966. An urban interstate, 187,570 vehicles cross it daily;
- IH 30 over Lake Ray Hubbard bridge in Dallas County that was built in 1995. An urban interstate, 141,93 vehicles cross it daily;
- IH 45 NB Conn C over IH 30 bridge in Dallas County that was built in 1961. An urban interstate, 138,390 vehicles cross it daily;
- IH 45 SB/NB over Crosstimbers Street bridge in Harris County built in 1960. An urban interstate, 116,204 vehicles cross it daily;
- IH 10 over 111th Street in Jefferson County that was built in 1958. An urban interstate, 89,604 vehicles cross it daily.
It is important to stress that vehicles would not be permitted to travel on these bridges if they were considered to be a hazard.
More than half of the bridges in Texas are located in rural areas.
In regards to proposed work, the report noted that 2,679 are to be replaced at a cost of $1,290,000,000; 71 require widening and rehabilitation at a cost of $30 million; 586 require rehabilitation at a cost of $277 million; nine require deck rehabilitation at a cost of $1 million; and 7,746 require other structural work at a cost of $4,643,00,000.
Photo courtesy of TxDOT
ARTBA pointed out that the "Data and cost estimates are from the Federal Highway Administration [FHWA] National Bridge Inventory [NBI], downloaded on July 3, 2023. Effective Jan. 1, 2018, FHWA changed the definition of structurally deficient as part of the final rule on highway and bridge performance measures, published May 20, 2017, pursuant to the 2012 federal aid highway bill Moving Ahead for Progress in the 21st Century Act [MAP-21]. Two measures that were previously used to classify bridges as structurally deficient are no longer used. This includes bridges where the overall structural evaluation was rated in poor or worse condition, or where the adequacy of waterway openings was insufficient."
In addition, "The new definition limits the classification to bridges where one of the key structural elements —the deck, superstructure, substructure or culverts — are rated in poor or worse condition. During inspection, the conditions of a variety of bridge elements are rated on a scale of 0 (failed condition) to 9 (excellent condition). A rating of 4 is considered "poor" condition. Cost estimates have been derived by ARTBA, based on 2022 average bridge replacement costs for structures on and off the National Highway System, published by FHWA. Bridge rehabilitation costs are estimated to be 68 percent of replacement costs. A bridge is considered to need repair if the structure has identified repairs as part of the NBI, a repair cost estimate is supplied by the bridge owner or the bridge is classified as structurally deficient. Please note that for a few states, the number of bridges needing to be repaired can vary significantly from year to year, and reflects the data entered by the state."
Lone Star State Spans
It has been a long time since the collapse of a bridge in Texas has made national news. Asked how the DOT would describe the efforts of its inspectors in determining problem bridges and helping to prepare bridge rehabilitation and reconstruction priority lists, Hammons replied: "All public-use bridges in Texas which carry vehicular traffic — and certain pedestrian bridges — undergo periodic routine safety inspections at their prescribed inspection intervals. Some structures undergo multiple types of specialized inspections, depending on the individual circumstances. The combination of findings from these inspections, help engineers to identify and quantify the performance of TxDOT's bridges.
"TxDOT has used the information from various inspections and condition surveys to help prioritize bridges and focus available funds on the bridges in most need," he added. "Prior to a bridge preservation project, TxDOT considers the benefits and costs of preservation compared to replacement to ensure that funds are maximized."
Bridges are prioritized for repair and replacement based on several factors. Once a need is identified, the time to repair or replace the bridge varies depending on the urgency and required actions.
"TxDOT uses available information to program bridge repair and replacement projects several years out in an effort to proactively preserve our bridges and avoid emergency projects," said Hammons.
The TxDOT Bridge Division is responsible for policy related to new bridge design in Texas.
Photo courtesy of TxDOT
"Bridge Division staff are involved in the design and review of projects across the state and promote innovations in materials, construction techniques, and maintenance. [The] Bridge Division serves as project advisors on research to advance innovations in these areas."
Bridge maintenance is crucial and it varies depending on structure type and location.
"Generally, TxDOT bridge maintenance includes maintenance of bridge joints, bearings, ensuring adequate drainage and maintaining bridge drains, sealing bridge decks, and performing concrete repairs," said Hammons. "TxDOT maintains electronic records for more than 56,000 bridges in our inventory. Electronic records include bridge information as required by the National Bridge Inspection Standards, including plans with design information, repair history, inspection reports, and other information."
"Texas bridges go through a painstaking design process that can sometimes take years," stated a TxDOT article. "Every inch of the bridge is studied, as engineers make certain the structure can perform under many types of conditions. These new structures benefit from advances in design techniques that target longer design lives for bridges than previous plans. And that level of detailed analysis is continued throughout the life of the bridge — during construction, inspections and ongoing maintenance."
"For nearly 40 years, TxDOT has been proactively inspecting bridges, making certain that all open, public-use bridges in the state are safe," it added. "That includes bridges both on the state highway system and all city and county bridges. In recent years, the ratings of Texas bridges have steadily improved. All public-use bridges in Texas undergo routine safety inspections every 24 months. The findings from these inspections help engineers to identify and quantify the performance of TxDOT's bridges. This high degree of self-scrutiny has resulted in significant improvements to the bridges on the state's transportation system."
The ATBA report in regards to Texas highlights the time and effort that TxDOT puts into bridge inspections and maintenance.
"The improvement in Texas' bridge rating is a direct reflection of TxDOT prioritizing bridge replacements and preservation, long-standing construction practices and standards, and the efforts to combat the most severe environments in Texas," stated the report. "TxDOT has aggressively pursued competitive grant dollars for bridges and aggressively prioritized the safety and maintenance of its bridges. Those grants also help local communities fund repairs to their bridges. This high degree of self-scrutiny has resulted in significant improvements to the bridges on the state's transportation system. If a bridge is open to vehicular traffic in Texas, you can be sure it's safe to cross." CEG
Irwin Rapoport
A journalist who started his career at a weekly community newspaper, Irwin Rapoport has written about construction and architecture for more than 15 years, as well as a variety of other subjects, such as recycling, environmental issues, business supply chains, property development, pulp and paper, agriculture, solar power and energy, and education. Getting the story right and illustrating the hard work and professionalism that goes into completing road, bridge, and building projects is important to him. A key element of his construction articles is to provide readers with an opportunity to see how general contractors and departments of transportation complete their projects and address challenges so that lessons learned can be shared with a wider audience.
Rapoport has a BA in History and a Minor in Political Science from Concordia University. His hobbies include hiking, birding, cycling, reading, going to concerts and plays, hanging out with friends and family, and architecture. He is keen to one day write an MA thesis on military and economic planning by the Great Powers prior to the start of the First World War.
Read more from Irwin Rapoport here.
Today's top stories
