US Bridges

FM 1798 over Irons Bayou

Fair

Rusk County, Texas · 0.25 MI S of FM 2867 · Structure no. 102010166902004

Built
1948
77 years old
Condition
Fair
inspected May 2023
Type
Culvert
Concrete
Length
39 ft
5 main spans
Daily traffic
306
2020 count
Owner
State
State Highway Agency

About this bridge

FM 1798 over Irons Bayou is a concrete culvert carrying FM 1798 over Irons Bayou in Rusk County, Texas. It was built in 1948, so it is 77 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 306 vehicles a day, roughly 16% of them trucks, projected to reach 310 by 2033. The structure is 39 ft (11.9 m) long and 37 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

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CarriesFM 1798
CrossesIrons Bayou
Location0.25 MI S of FM 2867
RouteState Highway 1798
CountyRusk County
StateTexas
Coordinates32.09828, -94.61016
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
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; action required to protect exposed foundations
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating36 US tons
Inventory rating27 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans5
Design loadUnknown
Structure length39 ft (11.9 m)
Longest span7 ft (2.1 m)
Deck width37 ft (11.4 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic306 (2020)
Projected traffic310 by 2033
Trucks16%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 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 1798 over Irons Bayou built?

It was built in 1948, making it 77 years old in 2025.

What condition is FM 1798 over Irons 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 May 2023.

How much traffic does FM 1798 over Irons Bayou carry?

About 306 vehicles per day (2020 count), of which roughly 16% are trucks.

How long is FM 1798 over Irons Bayou?

The structure is 39 ft (11.9 m) long with a longest span of 7 ft (2.1 m) and a deck 37 ft wide.

Who owns FM 1798 over Irons Bayou?

It is owned by the State Highway Agency.