US Bridges

Merrill Drive over Unnamed Canal

Good

St. Clair County, Michigan · Sec 1 Clay Twp · Structure no. 000000000010144

Built
1968
57 years old, rebuilt 2017
Condition
Good
inspected August 2023
Type
Slab
Wood or Timber
Length
25 ft
1 main span
Daily traffic
1,003
2016 count
Owner
County
County Highway Agency

About this bridge

Merrill Drive over Unnamed Canal is a wood or timber slab carrying Merrill Drive over Unnamed Canal in St. Clair County, Michigan. It was built in 1968 and reconstructed in 2017, so it is 57 years old, older than the Michigan average of 48.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 1,003 vehicles a day, roughly 7% of them trucks, projected to reach 1,225 by 2036. The structure is 25 ft (7.7 m) long and 30 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

Open in Google Maps
CarriesMerrill Drive
CrossesUnnamed Canal
LocationSec 1 Clay Twp
RouteCounty Highway 0
CountySt. Clair County
StateMichigan
Coordinates42.62902, -82.61172
Functional classUrban Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating88.2 US tons
Inventory rating67.9 US tons

Structure

Structure typeSlab
MaterialWood or Timber
DeckWood or timber
Main spans1
Design loadGreater than HL 93
Structure length25 ft (7.7 m)
Longest span20 ft (6.1 m)
Deck width30 ft (9.1 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,003 (2016)
Projected traffic1,225 by 2036
Trucks7%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Merrill Drive over Unnamed Canal built?

It was built in 1968, making it 57 years old in 2025. It was reconstructed in 2017.

What condition is Merrill Drive over Unnamed Canal in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in August 2023.

How much traffic does Merrill Drive over Unnamed Canal carry?

About 1,003 vehicles per day (2016 count), of which roughly 7% are trucks.

How long is Merrill Drive over Unnamed Canal?

The structure is 25 ft (7.7 m) long with a longest span of 20 ft (6.1 m) and a deck 30 ft wide.

Who owns Merrill Drive over Unnamed Canal?

It is owned by the County Highway Agency.