I-15 (SR-15) NBL
I-15 (SR-15) NBL in Approx. 300 W.3400 South, Salt Lake County, Utah received a condition grade of B (67/100). Built in 1999, the bridge carries 219K vehicles daily on I-15 (SR-15) NBL over Union Pacific Railroad.
I-15 (SR-15) NBL carries a B on the BridgeSafety Condition Score with 67/100. Most component ratings are solid; one or two may show wear consistent with the structure’s age, but the bridge is not flagged as structurally deficient.
The bridge was built in 1999, making it 27 years old — past the early-life period but still well within typical service life. Routine inspections and modest repair work are normal for bridges in this age band. I-15 (SR-15) NBL carries an average daily traffic count of 218,515 vehicles, with 6 lane(s) crossing Union Pacific Railroad. The owning agency is State Highway Agency; bridge inspection records flow into the federal NBI database annually.
Component Ratings
The riding surface, evaluated for cracking, spalling, and wear
Beams, girders, and trusses that support the deck
Piers, abutments, and foundations below the deck
Bridge Details
About This Bridge
I-15 (SR-15) NBL is a 27-year-old bridge located Approx. 300 W.3400 South in Salt Lake County, Utah. The bridge carries I-15 (SR-15) NBL over Union Pacific Railroad with 6 traffic lanes, handling approximately 219K vehicles per day. Built in 1999, the structure spans 95.6 meters.
The bridge received a Condition Grade of B (67/100) based on Federal Highway Administration inspection data. Its deck is rated 5/9 (fair), superstructure 7/9 (good), and substructure 6/9 (fair).
This bridge is owned and maintained by State Highway Agency.
Location Map
Frequently Asked Questions
I-15 (SR-15) NBL has a Condition Score of 67/100 (Grade B). Its deck is rated 5/9, superstructure 7/9, and substructure 6/9 on the NBI scale. The bridge is not classified as structurally deficient.
I-15 (SR-15) NBL was built in 1999, making it 27 years old. The average bridge age in the United States is 48 years.
I-15 (SR-15) NBL carries approximately 219K vehicles per day (average daily traffic). The bridge has 6 traffic lanes. It is 95.6 meters long and located on I-15 (SR-15) NBL in Approx. 300 W.3400 South, Salt Lake County, Utah.
No, I-15 (SR-15) NBL is not classified as structurally deficient. All three primary components (deck, superstructure, and substructure) are rated above 4 on the 0-9 NBI scale.
I-15 (SR-15) NBL is located Approx. 300 W.3400 South in Salt Lake County, Utah. The bridge carries I-15 (SR-15) NBL over Union Pacific Railroad. Its coordinates are 40.693517, -111.902378. It is maintained by State Highway Agency.
I-15 (SR-15) NBL carries I-15 (SR-15) NBL over Union Pacific Railroad. The bridge is 95.6 meters long and was built in 1999.
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.