ST 3
ST 3 in .16 KM E Braintree T.L., Norfolk County, Massachusetts received a condition grade of C (54/100). Built in 1957, the bridge carries 236K vehicles daily on ST 3 over HWY Summer ST.
ST 3 carries a C on the BridgeSafety Condition Score with 54/100. Component ratings sit in the middle of the FHWA NBI distribution; rehabilitation programming is likely on the owning agency’s medium-term horizon.
The bridge was built in 1957 and is now 69 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. ST 3 carries an average daily traffic count of 236,250 vehicles, with 6 lane(s) crossing HWY Summer ST. 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
ST 3 is a 69-year-old bridge located .16 KM E Braintree T.L. in Norfolk County, Massachusetts. The bridge carries ST 3 over HWY Summer ST with 6 traffic lanes, handling approximately 236K vehicles per day. Built in 1957 and reconstructed in 1978, the structure spans 19.1 meters.
The bridge received a Condition Grade of C (54/100) based on Federal Highway Administration inspection data. Its deck is rated 6/9 (fair), superstructure 5/9 (fair), and substructure 6/9 (fair).
This bridge is owned and maintained by State Highway Agency.
Location Map
Frequently Asked Questions
ST 3 has a Condition Score of 54/100 (Grade C). Its deck is rated 6/9, superstructure 5/9, and substructure 6/9 on the NBI scale. The bridge is not classified as structurally deficient.
ST 3 was built in 1957 and reconstructed in 1978, making it 69 years old. The average bridge age in the United States is 48 years.
ST 3 carries approximately 236K vehicles per day (average daily traffic). The bridge has 6 traffic lanes. It is 19.1 meters long and located on ST 3 in .16 KM E Braintree T.L., Norfolk County, Massachusetts.
No, ST 3 is not classified as structurally deficient. All three primary components (deck, superstructure, and substructure) are rated above 4 on the 0-9 NBI scale.
ST 3 is located .16 KM E Braintree T.L. in Norfolk County, Massachusetts. The bridge carries ST 3 over HWY Summer ST. Its coordinates are 42.199547, -70.970094. It is maintained by State Highway Agency.
ST 3 carries ST 3 over HWY Summer ST. The bridge is 19.1 meters long and was built in 1957, with reconstruction in 1978.
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.