BridgeSafety
Dallas County, TX · Structure #180570036402430

SH 121 SB

SH 121 SB in 1.55 MI SW Of Denton C/L, Dallas County, Texas received a condition grade of A (81/100). Built in 2009, the bridge carries 143K vehicles daily on SH 121 SB over W Sandy Lake RD.

SH 121 SB carries an A on the BridgeSafety Condition Score with 81/100. Deck, superstructure, and substructure ratings all sit in the better tier of the FHWA NBI distribution. The bridge is structurally sound by federal standards.

The bridge was built in 2009 and is 17 years old — relatively young against the U.S. bridge stock. Modern bridges built to current FHWA standards generally outperform older structures on condition ratings. SH 121 SB carries an average daily traffic count of 142,733 vehicles, with 4 lane(s) crossing W Sandy Lake RD. The owning agency is State Highway Agency; bridge inspection records flow into the federal NBI database annually.

A
81/100
81
Condition Score
143K
Daily Traffic
2009
Year Built
76.2m
Length

Component Ratings

DeckGood
7/9

The riding surface, evaluated for cracking, spalling, and wear

SuperstructureGood
8/9

Beams, girders, and trusses that support the deck

SubstructureGood
7/9

Piers, abutments, and foundations below the deck

Bridge Details

Road
SH 121 SB
Crosses Over
W Sandy Lake RD
State
Texas
County
Dallas County
Location
1.55 MI SW Of Denton C/L
Year Built
2009
Age
17 years
Daily Traffic
142,733
Lanes
4
Length
76.2 meters
Owner
State Highway Agency
Structure Number
180570036402430

About This Bridge

SH 121 SB is a 17-year-old bridge located 1.55 MI SW Of Denton C/L in Dallas County, Texas. The bridge carries SH 121 SB over W Sandy Lake RD with 4 traffic lanes, handling approximately 143K vehicles per day. Built in 2009, the structure spans 76.2 meters.

The bridge received a Condition Grade of A (81/100) based on Federal Highway Administration inspection data. Its deck is rated 7/9 (good), superstructure 8/9 (good), and substructure 7/9 (good).

This bridge is owned and maintained by State Highway Agency.

Location Map

1.55 MI SW Of Denton C/L, Dallas County, Texas

32.973178, -97.028561

Open in Google Maps →

Frequently Asked Questions

SH 121 SB has a Condition Score of 81/100 (Grade A). Its deck is rated 7/9, superstructure 8/9, and substructure 7/9 on the NBI scale. The bridge is not classified as structurally deficient.

SH 121 SB was built in 2009, making it 17 years old. The average bridge age in the United States is 48 years.

SH 121 SB carries approximately 143K vehicles per day (average daily traffic). The bridge has 4 traffic lanes. It is 76.2 meters long and located on SH 121 SB in 1.55 MI SW Of Denton C/L, Dallas County, Texas.

No, SH 121 SB is not classified as structurally deficient. All three primary components (deck, superstructure, and substructure) are rated above 4 on the 0-9 NBI scale.

SH 121 SB is located 1.55 MI SW Of Denton C/L in Dallas County, Texas. The bridge carries SH 121 SB over W Sandy Lake RD. Its coordinates are 32.973178, -97.028561. It is maintained by State Highway Agency.

SH 121 SB carries SH 121 SB over W Sandy Lake RD. The bridge is 76.2 meters long and was built in 2009.

Last updated:

Condition Score is calculated from deck (33%), superstructure (33%), and substructure (34%) NBI ratings with an age penalty for bridges over 50 years.

Source: FHWA National Bridge Inventory, 2026.