Structure M120194DYDOTNBI · Middlesex County, MA

ST 16 Myst Val Pky over Comb Mystic R & Ped/bky

Carries ST 16 Myst Val Pky over Comb Mystic R & Ped/bky, .3 Mi E Of ST RTE 38.

Overall conditionFair

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

How ratings work
Decksets the rating5/9 · Fair
Superstructure6/9 · Satisfactory
Substructure6/9 · Satisfactory
Channelnot part of overall7/9 · Good
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT308 FT OVERALL50 FT0ELEVATION · LENGTHS TO SCALE
Deck 5/9 · sets the ratingSuperstructure 6/9Substructure 6/9

308 ft end to end, longest span 140 ft: about 4 semi-trucks nose to tail. 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.

Built198838 years old
Length307.7 ft93.8 m
Daily traffic41,250counted 2024
Last inspectedOctober 2024every 24 months

Location

StateMassachusetts
CountyMiddlesex
Location.3 Mi E Of ST RTE 38
CarriesST 16 Myst Val Pky
CrossesComb Mystic R & Ped/bky
Coordinates42.40590, -71.09642

Physical Characteristics

MaterialSteel Continuous
DesignStringer/Multi-beam
Total Length307.7 ft (93.8 m)
Max Span140.1 ft (42.7 m)
Deck Width108.6 ft (33.1 m)
Deck Area3104.8 sq m
Main Spans3
Year Built1988

Traffic

Avg Daily Traffic41,250 (2024)
Truck Traffic8%
Lanes On Bridge4

Inspection & Ownership

Last InspectionOctober 2024
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour Critical8 — Stable, low risk
Structure NumberM120194DYDOTNBI

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.

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