IH 35 SB
IH 35 SB in 0.3 MI S Of Sh 29, Williamson County, Texas received a condition grade of B (61/100). Built in 1965, the bridge carries 517K vehicles daily on IH 35 SB over South San Gabriel River.
IH 35 SB carries a B on the BridgeSafety Condition Score with 61/100. Most component ratings are solid; one or two may show wear consistent with the structure’s age, but the bridge is not flagged as structurally deficient.
The bridge was built in 1965 and is now 61 years old, at or past the typical 50-year design life for bridges of its vintage. Maintenance and inspection cycles are correspondingly more involved than for newer structures. IH 35 SB carries an average daily traffic count of 517,256 vehicles, with 3 lane(s) crossing South San Gabriel River. The owning agency is State Highway Agency; bridge inspection records flow into the federal NBI database annually.
Component Ratings
The riding surface, evaluated for cracking, spalling, and wear
Beams, girders, and trusses that support the deck
Piers, abutments, and foundations below the deck
Bridge Details
About This Bridge
IH 35 SB is a 61-year-old bridge located 0.3 MI S Of Sh 29 in Williamson County, Texas. The bridge carries IH 35 SB over South San Gabriel River with 3 traffic lanes, handling approximately 517K vehicles per day. Built in 1965 and reconstructed in 2001, the structure spans 158.5 meters.
The bridge received a Condition Grade of B (61/100) based on Federal Highway Administration inspection data. Its deck is rated 6/9 (fair), superstructure 6/9 (fair), and substructure 6/9 (fair).
This bridge is owned and maintained by State Highway Agency.
Location Map
Frequently Asked Questions
IH 35 SB has a Condition Score of 61/100 (Grade B). Its deck is rated 6/9, superstructure 6/9, and substructure 6/9 on the NBI scale. The bridge is not classified as structurally deficient.
IH 35 SB was built in 1965 and reconstructed in 2001, making it 61 years old. The average bridge age in the United States is 48 years.
IH 35 SB carries approximately 517K vehicles per day (average daily traffic). The bridge has 3 traffic lanes. It is 158.5 meters long and located on IH 35 SB in 0.3 MI S Of Sh 29, Williamson County, Texas.
No, IH 35 SB is not classified as structurally deficient. All three primary components (deck, superstructure, and substructure) are rated above 4 on the 0-9 NBI scale.
IH 35 SB is located 0.3 MI S Of Sh 29 in Williamson County, Texas. The bridge carries IH 35 SB over South San Gabriel River. Its coordinates are 30.625933, -97.691122. It is maintained by State Highway Agency.
IH 35 SB carries IH 35 SB over South San Gabriel River. The bridge is 158.5 meters long and was built in 1965, with reconstruction in 2001.
Condition Score is calculated from deck (33%), superstructure (33%), and substructure (34%) NBI ratings with an age penalty for bridges over 50 years.
Source: FHWA National Bridge Inventory, 2026.