US Bridges

FM 121 over W Sister Grove Creek

Good

Grayson County, Texas · 3.4 MI E of US 75 · Structure no. 010920072902183

Built
2008
17 years old
Condition
Good
inspected March 2023
Type
Slab
Prestressed Concrete
Length
150 ft
3 main spans
Daily traffic
3,962
2020 count
Owner
State
State Highway Agency

About this bridge

FM 121 over W Sister Grove Creek is a prestressed concrete slab carrying FM 121 over W Sister Grove Creek in Grayson County, Texas. It was built in 2008, so it is 17 years old, younger than the Texas average of 44.4 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 3,962 vehicles a day, roughly 10% of them trucks, projected to reach 4,050 by 2033. The structure is 150 ft (45.7 m) long and 46 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesFM 121
CrossesW Sister Grove Creek
Location3.4 MI E of US 75
RouteState Highway 121
CountyGrayson County
StateTexas
Coordinates33.42899, -96.53162
Functional classRural Major Collector

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour evaluation has not been made
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating60 US tons
Inventory rating36 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHL 93
Structure length150 ft (45.7 m)
Longest span50 ft (15.2 m)
Deck width46 ft (14 m)
Roadway width43 ft (13.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,962 (2020)
Projected traffic4,050 by 2033
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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 proposedOther structural work, including hydraulic replacements
Estimated improvement cost$5,000
NavigationNo navigation control on waterway

Frequently asked questions

When was FM 121 over W Sister Grove Creek built?

It was built in 2008, making it 17 years old in 2025.

What condition is FM 121 over W Sister Grove Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in March 2023.

How much traffic does FM 121 over W Sister Grove Creek carry?

About 3,962 vehicles per day (2020 count), of which roughly 10% are trucks.

How long is FM 121 over W Sister Grove Creek?

The structure is 150 ft (45.7 m) long with a longest span of 50 ft (15.2 m) and a deck 46 ft wide.

Who owns FM 121 over W Sister Grove Creek?

It is owned by the State Highway Agency.