US Bridges

ST110 Merrimack ST over I 495

Fair

Essex County, Massachusetts · 1 MI S of ST-213 · Structure no. M170322YFDOTNBI

Built
1962
63 years old
Condition
Fair
inspected October 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
354 ft
5 main spans
Daily traffic
15,458
2024 count
Owner
State
State Highway Agency

About this bridge

ST110 Merrimack ST over I 495 is a steel stringer/multi-beam or girder carrying ST110 Merrimack ST over I 495 in Essex County, Massachusetts. It was built in 1962, so it is 63 years old, younger 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 15,458 vehicles a day, roughly 4% of them trucks, projected to reach 71,858 by 2031. The structure is 354 ft (107.9 m) long and 62 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesST110 Merrimack ST
CrossesI 495
Location1 MI S of ST-213
RouteState Highway 110
CountyEssex County
StateMassachusetts
Coordinates42.72818, -71.13903
Functional classUrban Minor Arterial

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
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 inspectionOctober 2024
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 rating57.9 US tons
Inventory rating35.4 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans5
Design loadH 20
Structure length354 ft (107.9 m)
Longest span88 ft (26.8 m)
Deck width62 ft (19 m)
Roadway width48 ft (14.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic15,458 (2024)
Projected traffic71,858 by 2031
Trucks4%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesHighway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$20 million (2025 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was ST110 Merrimack ST over I 495 built?

It was built in 1962, making it 63 years old in 2025.

What condition is ST110 Merrimack ST over I 495 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 October 2024.

How much traffic does ST110 Merrimack ST over I 495 carry?

About 15,458 vehicles per day (2024 count), of which roughly 4% are trucks.

How long is ST110 Merrimack ST over I 495?

The structure is 354 ft (107.9 m) long with a longest span of 88 ft (26.8 m) and a deck 62 ft wide.

Who owns ST110 Merrimack ST over I 495?

It is owned by the State Highway Agency.