I-77
I-77 in 11.0 MI N Of Rock Hill, York County, South Carolina received a condition grade of F (0/100). Built in 1973, the bridge carries 131K vehicles daily on I-77 over Steel Creek. It is classified as structurally deficient.
I-77 carries an F on the BridgeSafety Condition Score with 0/100 — the bottom tier of the FHWA NBI distribution. Component ratings flag the structure for near-term rehabilitation or replacement; the bridge may remain open to traffic but is on the priority list for action.
The bridge was built in 1973 and is now 53 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. I-77 carries an average daily traffic count of 130,800 vehicles, with 4 lane(s) crossing Steel Creek. 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-77 is a 53-year-old bridge located 11.0 MI N Of Rock Hill in York County, South Carolina. The bridge carries I-77 over Steel Creek with 4 traffic lanes, handling approximately 131K vehicles per day. Built in 1973, the structure spans 16.2 meters.
The bridge received a Condition Grade of F (0/100) based on Federal Highway Administration inspection data. Its deck is rated 0/9 (serious), superstructure 0/9 (serious), and substructure 0/9 (serious). The bridge is classified as structurally deficient, meaning at least one major component is rated 4 or below, this signals a need for repair or replacement but does not necessarily indicate an immediate safety hazard.
This bridge is owned and maintained by State Highway Agency.
Location Map
Frequently Asked Questions
I-77 has a Condition Score of 0/100 (Grade F). Its deck is rated 0/9, superstructure 0/9, and substructure 0/9 on the NBI scale. The bridge is classified as structurally deficient.
I-77 was built in 1973, making it 53 years old. The average bridge age in the United States is 48 years.
I-77 carries approximately 131K vehicles per day (average daily traffic). The bridge has 4 traffic lanes. It is 16.2 meters long and located on I-77 in 11.0 MI N Of Rock Hill, York County, South Carolina.
Yes, I-77 is classified as structurally deficient because at least one of its primary components (deck, superstructure, or substructure) is rated 4 or below on the 0-9 NBI scale. This does not necessarily mean it is unsafe, but it requires significant repair or replacement.
I-77 is located 11.0 MI N Of Rock Hill in York County, South Carolina. The bridge carries I-77 over Steel Creek. Its coordinates are 35.070278, -80.948889. It is maintained by State Highway Agency.
I-77 carries I-77 over Steel Creek. The bridge is 16.2 meters long and was built in 1973.
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.