INTERSTATE 15
INTERSTATE 15 in 08-Sbd-015-3.05-Rcuc, San Bernardino County, California received a condition grade of B (77/100). Built in 1974, the bridge carries 204K vehicles daily on INTERSTATE 15 over Fourth Street.
INTERSTATE 15 carries a B on the BridgeSafety Condition Score with 77/100. 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 1974 and is now 52 years old, at or past the typical 50-year design life for bridges of its vintage. Maintenance and inspection cycles are correspondingly more involved than for newer structures. INTERSTATE 15 carries an average daily traffic count of 204,000 vehicles, with 13 lane(s) crossing Fourth Street. 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
INTERSTATE 15 is a 52-year-old bridge located 08-Sbd-015-3.05-Rcuc in San Bernardino County, California. The bridge carries INTERSTATE 15 over Fourth Street with 13 traffic lanes, handling approximately 204K vehicles per day. Built in 1974 and reconstructed in 2011, the structure spans 49 meters.
The bridge received a Condition Grade of B (77/100) based on Federal Highway Administration inspection data. Its deck is rated 7/9 (good), superstructure 7/9 (good), and substructure 7/9 (good).
This bridge is owned and maintained by State Highway Agency.
Location Map
Frequently Asked Questions
INTERSTATE 15 has a Condition Score of 77/100 (Grade B). Its deck is rated 7/9, superstructure 7/9, and substructure 7/9 on the NBI scale. The bridge is not classified as structurally deficient.
INTERSTATE 15 was built in 1974 and reconstructed in 2011, making it 52 years old. The average bridge age in the United States is 48 years.
INTERSTATE 15 carries approximately 204K vehicles per day (average daily traffic). The bridge has 13 traffic lanes. It is 49 meters long and located on INTERSTATE 15 in 08-Sbd-015-3.05-Rcuc, San Bernardino County, California.
No, INTERSTATE 15 is not classified as structurally deficient. All three primary components (deck, superstructure, and substructure) are rated above 4 on the 0-9 NBI scale.
INTERSTATE 15 is located 08-Sbd-015-3.05-Rcuc in San Bernardino County, California. The bridge carries INTERSTATE 15 over Fourth Street. Its coordinates are 34.077006, -117.544425. It is maintained by State Highway Agency.
INTERSTATE 15 carries INTERSTATE 15 over Fourth Street. The bridge is 49 meters long and was built in 1974, with reconstruction in 2011.
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.