US Bridges

SH 121 Nbfr over Sister Grove Creek

Good

Collin County, Texas · 5.85 MI NE of FM 545 · Structure no. 180430054903235

Built
2021
4 years old
Condition
Good
inspected September 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
430 ft
4 main spans
Daily traffic
15,684
2020 count
Owner
State
State Highway Agency

About this bridge

SH 121 Nbfr over Sister Grove Creek is a prestressed concrete stringer/multi-beam or girder carrying SH 121 Nbfr over Sister Grove Creek in Collin County, Texas. It was built in 2021, so it is 4 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 15,684 vehicles a day, roughly 10% of them trucks, projected to reach 22,271 by 2040. The structure is 430 ft (131.1 m) long and 38 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesSH 121 Nbfr
CrossesSister Grove Creek
Location5.85 MI NE of FM 545
RouteState Highway 121
CountyCollin County
StateTexas
Coordinates33.33231, -96.48142
Functional classRural Principal Arterial - Other

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.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
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 typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadHL 93
Structure length430 ft (131.1 m)
Longest span120 ft (36.6 m)
Deck width38 ft (11.6 m)
Roadway width35 ft (10.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic15,684 (2020)
Projected traffic22,271 by 2040
Trucks10%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 km)
TollOn a free road
National Highway SystemYes

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 SH 121 Nbfr over Sister Grove Creek built?

It was built in 2021, making it 4 years old in 2025.

What condition is SH 121 Nbfr over 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 September 2023.

How much traffic does SH 121 Nbfr over Sister Grove Creek carry?

About 15,684 vehicles per day (2020 count), of which roughly 10% are trucks.

How long is SH 121 Nbfr over Sister Grove Creek?

The structure is 430 ft (131.1 m) long with a longest span of 120 ft (36.6 m) and a deck 38 ft wide.

Who owns SH 121 Nbfr over Sister Grove Creek?

It is owned by the State Highway Agency.