US Bridges

FM 791 over San Antonio River

Fair

Karnes County, Texas · 2.4 MI SW of FM 887 · Structure no. 161290112201002

Built
1949
76 years old
Condition
Fair
inspected June 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
310 ft
3 main spans
Daily traffic
1,225
2022 count
Owner
State
State Highway Agency

About this bridge

FM 791 over San Antonio River is a steel continuous stringer/multi-beam or girder carrying FM 791 over San Antonio River in Karnes County, Texas. It was built in 1949, so it is 76 years old, older than the Texas average of 44.4 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 1,225 vehicles a day, roughly 29% of them trucks, projected to reach 1,715 by 2042. The structure is 310 ft (94.5 m) long and 26 ft wide. If it were closed, the detour would be 14.9 mi (24 km).

CarriesFM 791
CrossesSan Antonio River
Location2.4 MI SW of FM 887
RouteState Highway 791
StateTexas
Coordinates28.95154, -98.06437
Functional classRural Major Collector

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating44 US tons
Inventory rating26 US tons

Structure

MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3 (+2 approach)
Design loadOther
Structure length310 ft (94.5 m)
Longest span90 ft (27.4 m)
Deck width26 ft (7.8 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,225 (2022)
Projected traffic1,715 by 2042
Trucks29%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed14.9 mi (24 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusPossibly eligible for the National Register; requires further investigation
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$455,000
NavigationNo navigation control on waterway

Frequently asked questions

When was FM 791 over San Antonio River built?

It was built in 1949, making it 76 years old in 2025.

What condition is FM 791 over San Antonio River in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in June 2024.

How much traffic does FM 791 over San Antonio River carry?

About 1,225 vehicles per day (2022 count), of which roughly 29% are trucks.

How long is FM 791 over San Antonio River?

The structure is 310 ft (94.5 m) long with a longest span of 90 ft (27.4 m) and a deck 26 ft wide.

Who owns FM 791 over San Antonio River?

It is owned by the State Highway Agency.