US Bridges

FM 491 over Willacy Main Canal

Fair

Hidalgo County, Texas · 0.80 MI W of FM 2629 · Structure no. 211090086101006

Built
1956
69 years old
Condition
Fair
inspected May 2023
Type
Slab
Concrete
Length
150 ft
6 main spans
Daily traffic
805
2020 count
Owner
State
State Highway Agency

About this bridge

FM 491 over Willacy Main Canal is a concrete slab carrying FM 491 over Willacy Main Canal in Hidalgo County, Texas. It was built in 1956, so it is 69 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 805 vehicles a day, roughly 35% of them trucks, projected to reach 910 by 2033. The structure is 150 ft (45.7 m) long and 25 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

Location

Open in Google Maps
CarriesFM 491
CrossesWillacy Main Canal
Location0.80 MI W of FM 2629
RouteState Highway 491
CountyHidalgo County
StateTexas
Coordinates26.34217, -97.90774
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 protection7 GoodSome minor problems.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour evaluation has not been made
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating58 US tons
Inventory rating30 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans6
Design loadOther
Structure length150 ft (45.7 m)
Longest span25 ft (7.6 m)
Deck width25 ft (7.7 m)
Roadway width23 ft (7.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic805 (2020)
Projected traffic910 by 2033
Trucks35%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.1 mi (13 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was FM 491 over Willacy Main Canal built?

It was built in 1956, making it 69 years old in 2025.

What condition is FM 491 over Willacy Main Canal 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 May 2023.

How much traffic does FM 491 over Willacy Main Canal carry?

About 805 vehicles per day (2020 count), of which roughly 35% are trucks.

How long is FM 491 over Willacy Main Canal?

The structure is 150 ft (45.7 m) long with a longest span of 25 ft (7.6 m) and a deck 25 ft wide.

Who owns FM 491 over Willacy Main Canal?

It is owned by the State Highway Agency.