AUSTIN (KXAN) – Central Texas is home to more than 4,300 bridges inspected by the state, and 780 of them have been classified as functionally obsolete or structurally deficient, according to data from the Texas Department of Transportation.

The bridges TxDOT inspects range from iconic postcard-worthy spans like the arched Pennybacker Bridge crossing Lake Austin (which is not deficient) to dry-creek culverts that drivers might not even notice passing over. TxDOT assigns a sufficiency rating from 0 to 100 — a rating below 50 is poor — for each bridge it inspects. Those rating help guide local decisions for spending on improvements and repairs.

Bridge collapses, like on in Pittsburgh in January, highlight the need for inspections and improvements to ones in poor condition. President Joe Biden’s $1 trillion infrastructure spending bill allotted $27 billion for bridge repairs across the country through the Bridge Formula Program.

Austin has no major bridges in poor condition, but the city identified five major bridges in need of significant rehabilitation or replacement, according to a city report released in late February. Of the 452 Austin bridges noted in the report, 29% are past their design lifespan of 50 years.

A bridge’s sufficiency rating takes several criteria into account, including the deck width, railings, approach design and more. Bridges that don’t “completely comply with today’s more rigorous standards are technically categorized as ‘obsolete,'” according to Kyle Carvell, public information officer with the Austin Public Works Department.

“A fair amount of obsolescence in structures built 40 or more years ago should be expected and may be acceptable for a while. Alternatively, a bridge with serious structural problems would be technically categorized as ‘deficient,'” Carvell wrote in an email.

KXAN has used TxDOT’s data to map each bridge in Travis and 11 surrounding counties. You can click or tap a point to find a bridge’s sufficiency rating, age and whether it has been classified as deficient or obsolete. Points with a lighter color have a lower rating, meaning they are in worse condition than others.

The bridge report released in February by Austin’s Public Works Department says none of the 452 major bridges inspected by TxDOT have a sufficiency ratings below 50 and none are deficient, but that report doesn’t provide a complete picture of local bridges.

KXAN analyzed TxDOT’s data, which includes far more bridges in Austin than the 452 outlined in the Public Works report. TxDOT’s latest records shows there are 10 bridges in Austin with a sufficiency rating below 50, or categorized as deficient or both.

Carvell said the city did not include those bridges rated poor and deficient in its report because they “are not the responsibility of Public Works” and “not part of the 452 TXDOT inspect for us.”

Carvel said most of those poor or deficient bridges are TxDOT’s responsibility, a few belong to the railroad and one – the Dean Keaton pedestrian walkway – is the University of Texas at Austin’s.

KXAN also found some of the sufficiency rating used by the Public Works Department in its report are higher than current ratings available from TxDOT. For example, the city’s rating for the Lamar Boulevard bridge over Lady Bird Lake is 73, but TxDOT’s current rating for the same bridge is 50.7, which is 22 points lower and barely above a poor rating.

Carvell said the city based its report data on inspection records provided by TxDOT in 2020, and the data available online from TxDOT has been updated more recently.

Austin Bridges over 100 years old

There are 40 bridges in Central Texas that were originally built more than 100 years ago, including 12 in or near Austin. Despite being the oldest spans in the area, none in Austin have a sufficiency rating in the “poor” range — below 50 — according to TxDOT data.

In Lee County, 27% of its 138 bridges are functionally obsolete, which is the highest percent of all 12 Central Texas counties we analyzed, according to TxDOT data. Travis County has the most bridges in the area with 1,514 monitored by TxDOT, followed by Williamson County with 1,100.

Overall Texas has more than 55,000 bridges, the most of any state. The percent of bridges in poor condition has decreased in the past 20 years, and the state is “well below” the national average for percent of bridges in poor condition, according to a 2020 TxDOT report.