US Bridges

HWY Mill ST over Water Assabet River

Fair

Middlesex County, Massachusetts · 0.2 Mi. N. of Rt. 62 · Structure no. M1000325UMUNNBI

Built
1937
88 years old
Condition
Fair
inspected September 2023
Type
Arch - Deck
Steel
Length
70 ft
3 main spans
Daily traffic
1,040
2014 count
Owner
Town / Township
Town or Township Highway Agency

About this bridge

HWY Mill ST over Water Assabet River is a steel arch - deck carrying HWY Mill ST over Water Assabet River in Middlesex County, Massachusetts. It was built in 1937, so it is 88 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 1,040 vehicles a day, roughly 1% of them trucks, projected to reach 1,642 by 2032. The structure is 70 ft (21.3 m) long and 34 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesHWY Mill ST
CrossesWater Assabet River
Location0.2 Mi. N. of Rt. 62
RouteCity Street 0
CountyMiddlesex County
StateMassachusetts
Coordinates42.4309, -71.46672
Functional classUrban Local

Condition and inspection

Fair

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

ComponentRatingMeaning
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.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating110.1 US tons
Inventory rating110.1 US tons

Structure

Structure typeArch - Deck
MaterialSteel
DeckNot applicable
Main spans3
Design loadUnknown
Structure length70 ft (21.3 m)
Longest span23 ft (7 m)
Deck width34 ft (10.5 m)
Roadway width22 ft (6.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,040 (2014)
Projected traffic1,642 by 2032
Trucks1%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerTown or Township Highway Agency
Maintained byTown or Township Highway Agency
Historic statusEligible for the National Register of Historic Places
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$2.3 million (2025 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was HWY Mill ST over Water Assabet River built?

It was built in 1937, making it 88 years old in 2025.

What condition is HWY Mill ST over Water Assabet River 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 September 2023.

How much traffic does HWY Mill ST over Water Assabet River carry?

About 1,040 vehicles per day (2014 count), of which roughly 1% are trucks.

How long is HWY Mill ST over Water Assabet River?

The structure is 70 ft (21.3 m) long with a longest span of 23 ft (7 m) and a deck 34 ft wide.

Who owns HWY Mill ST over Water Assabet River?

It is owned by the Town or Township Highway Agency.