Structure L04042318DOTNBI · Essex County, MA

HWY S Union Conn over HWY South ST

Carries HWY S Union Conn over HWY South ST, At Andover Town Line.

Overall conditionFair

Set by its lowest-rated component: Deck and Superstructure at 5 of 9.

How ratings work
Decksets the rating5/9 · Fair
Superstructuresets the rating5/9 · Fair
Substructure6/9 · Satisfactory
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT122 FT OVERALL25 FT0ELEVATION · LENGTHS TO SCALE
Deck 5/9 · sets the ratingSuperstructure 5/9 · sets the ratingSubstructure 6/9

122 ft end to end, longest span 47 ft. Lengths and the semi-truck on the deck are drawn to the same scale. Each part is colored by its latest inspection rating. The inventory records lengths but not heights or the layout of the shorter spans, so those are drawn as typical for a multi-beam bridge.

Built196264 years old
Length122.0 ft37.2 m
Daily traffic10,100counted 2025
Last inspectedJanuary 2025every 24 months

Location

StateMassachusetts
CountyEssex
LocationAt Andover Town Line
CarriesHWY S Union Conn
CrossesHWY South ST
Coordinates42.68329, -71.15306

Physical Characteristics

MaterialSteel
DesignStringer/Multi-beam
Total Length122.0 ft (37.2 m)
Max Span46.9 ft (14.3 m)
Deck Width32.8 ft (10 m)
Deck Area372 sq m
Main Spans3
Year Built1962

Traffic

Avg Daily Traffic10,100 (2025)
Truck Traffic6%
Lanes On Bridge1
Lanes Under Bridge2

Inspection & Ownership

Last InspectionJanuary 2025
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour CriticalNot applicable
Structure NumberL04042318DOTNBI

How Bridge Ratings Work

Inspectors rate each major part of a bridge (the deck you drive on, the superstructure of beams that holds it up, and the substructure of piers and abutments beneath) on a 0–9 scale. A bridge's overall condition is its lowest of those ratings, so one deteriorated component makes the whole bridge "poor."

0Failed
1Imminent failure
2Critical
3Serious
4Poor
5Fair
6Satisfactory
7Good
8Very good
9Excellent
Good · lowest component 7–9
Fair · lowest component 5–6
Poor · lowest component 0–4

A poor rating is not a closure. It means the bridge is flagged for priority repair or replacement; bridges judged unsafe are closed or posted with weight limits. The waterway (channel) rating is reported, but it does not count toward the overall classification.

Nearby Bridges