US Bridges

FM 521 over Linnville Bayou

Fair

Matagorda County, Texas · 1.6 MI NE of FM 457 · Structure no. 131580084701022

Built
2006
19 years old
Condition
Fair
inspected December 2024
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
115 ft
1 main span
Daily traffic
2,980
2023 count
Owner
State
State Highway Agency

About this bridge

FM 521 over Linnville Bayou is a prestressed concrete box beam or girders - multiple carrying FM 521 over Linnville Bayou in Matagorda County, Texas. It was built in 2006, so it is 19 years old, younger 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 2,980 vehicles a day, roughly 6% of them trucks, projected to reach 5,602 by 2042. The structure is 115 ft (35.1 m) long and 47 ft wide. If it were closed, the detour would be 24.2 mi (39 km).

Location

Open in Google Maps
CarriesFM 521
CrossesLinnville Bayou
Location1.6 MI NE of FM 457
RouteState Highway 521
CountyMatagorda County
StateTexas
Coordinates28.95167, -95.71119
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
Deck8 Very GoodNo problems noted.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionDecember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating60 US tons
Inventory rating36 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length115 ft (35.1 m)
Longest span115 ft (35.1 m)
Deck width47 ft (14.3 m)
Roadway width44 ft (13.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,980 (2023)
Projected traffic5,602 by 2042
Trucks6%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed24.2 mi (39 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was FM 521 over Linnville Bayou built?

It was built in 2006, making it 19 years old in 2025.

What condition is FM 521 over Linnville Bayou 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 December 2024.

How much traffic does FM 521 over Linnville Bayou carry?

About 2,980 vehicles per day (2023 count), of which roughly 6% are trucks.

How long is FM 521 over Linnville Bayou?

The structure is 115 ft (35.1 m) long with a longest span of 115 ft (35.1 m) and a deck 47 ft wide.

Who owns FM 521 over Linnville Bayou?

It is owned by the State Highway Agency.