US Bridges

US 87 SB over Llano River

Fair

Mason County, Texas · 1.30 MI NW of RM 152 · Structure no. 141570007104018

Built
1931
94 years old
Condition
Fair
inspected June 2023
Type
Truss - Thru
Steel
Length
902 ft
2 main spans
Daily traffic
1,628
2020 count
Owner
State
State Highway Agency

About this bridge

US 87 SB over Llano River is a steel truss - thru carrying US 87 SB over Llano River in Mason County, Texas. It was built in 1931, so it is 94 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 5 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 1,628 vehicles a day, roughly 18% of them trucks, projected to reach 890 by 2033. The structure is 902 ft (274.9 m) long and 25 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesUS 87 SB
CrossesLlano River
Location1.30 MI NW of RM 152
RouteU.S. Route 87
CountyMason County
StateTexas
Coordinates30.66107, -99.10979
Functional classRural Minor Arterial

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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating48 US tons
Inventory rating29 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckConcrete, cast-in-place
Main spans2 (+14 approach)
Design loadH 15
Structure length902 ft (274.9 m)
Longest span182 ft (55.5 m)
Deck width25 ft (7.6 m)
Roadway width22 ft (6.6 m)
Vertical clearance over deck15 ft (4.5 m)

Traffic and service

Average daily traffic1,628 (2020)
Projected traffic890 by 2033
Trucks18%
Lanes on structure1
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusListed on the National Register of Historic Places
Work proposedOther structural work, including hydraulic replacements
Estimated improvement cost$50,000
NavigationNo navigation control on waterway

Frequently asked questions

When was US 87 SB over Llano River built?

It was built in 1931, making it 94 years old in 2025.

What condition is US 87 SB over Llano 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 2023.

How much traffic does US 87 SB over Llano River carry?

About 1,628 vehicles per day (2020 count), of which roughly 18% are trucks.

How long is US 87 SB over Llano River?

The structure is 902 ft (274.9 m) long with a longest span of 182 ft (55.5 m) and a deck 25 ft wide.

Who owns US 87 SB over Llano River?

It is owned by the State Highway Agency.