US Bridges

US 1 Nb/Lowr Deck over Other Relief

Fair

Suffolk County, Massachusetts · Toll Pl Lower · Structure no. B160174X1DOTNBI

Built
1950
75 years old
Condition
Fair
inspected November 2023
Type
Girder and Floorbeam System
Steel
Length
1,072 ft
12 main spans
Daily traffic
41,988
2022 count
Owner
State
State Highway Agency

About this bridge

US 1 Nb/Lowr Deck over Other Relief is a steel girder and floorbeam system carrying US 1 Nb/Lowr Deck over Other Relief in Suffolk County, Massachusetts. It was built in 1950, so it is 75 years old, older than the Massachusetts average of 63.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 41,988 vehicles a day, roughly 7% of them trucks, projected to reach 70,595 by 2032. The structure is 1,072 ft (326.7 m) long and 42 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesUS 1 Nb/Lowr Deck
CrossesOther Relief
LocationToll Pl Lower
RouteU.S. Route 1
CountySuffolk County
StateMassachusetts
Coordinates42.3819, -71.05016
Functional classUrban Principal Arterial - Other Freeway or Expressway

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionNovember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Approach roadway alignment7: Better than present minimum criteria
Operating rating38.9 US tons
Inventory rating24.5 US tons

Structure

Structure typeGirder and Floorbeam System
MaterialSteel
DeckClosed grating
Main spans12
Design loadHS 20
Structure length1,072 ft (326.7 m)
Longest span116 ft (35.4 m)
Deck width42 ft (12.7 m)
Roadway width36 ft (11 m)
Vertical clearance over deck16 ft (4.9 m)

Traffic and service

Average daily traffic41,988 (2022)
Projected traffic70,595 by 2032
Trucks7%
Lanes on structure3
Traffic directionOne-way traffic
CarriesHighway
CrossesOther
Detour if closed5 mi (8 km)
TollToll bridge
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusPossibly eligible for the National Register; requires further investigation
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$40.4 million (2025 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was US 1 Nb/Lowr Deck over Other Relief built?

It was built in 1950, making it 75 years old in 2025.

What condition is US 1 Nb/Lowr Deck over Other Relief in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in November 2023.

How much traffic does US 1 Nb/Lowr Deck over Other Relief carry?

About 41,988 vehicles per day (2022 count), of which roughly 7% are trucks.

How long is US 1 Nb/Lowr Deck over Other Relief?

The structure is 1,072 ft (326.7 m) long with a longest span of 116 ft (35.4 m) and a deck 42 ft wide.

Who owns US 1 Nb/Lowr Deck over Other Relief?

It is owned by the State Highway Agency.