US Bridges

M-18 over Backus Creek

Good

Roscommon County, Michigan · 9.8 MI S of BUS-75 · Structure no. 000000000009017

Built
2019
6 years old
Condition
Good
inspected July 2024
Type
Culvert
Concrete
Length
22 ft
1 main span
Daily traffic
2,550
2017 count
Owner
State
State Highway Agency

About this bridge

M-18 over Backus Creek is a concrete culvert carrying M-18 over Backus Creek in Roscommon County, Michigan. It was built in 2019, so it is 6 years old, younger 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 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 2,550 vehicles a day, roughly 4% of them trucks, projected to reach 2,850 by 2040. The structure is 22 ft (6.7 m) long.

Location

Open in Google Maps
CarriesM-18
CrossesBackus Creek
Location9.8 MI S of BUS-75
RouteState Highway 18
CountyRoscommon County
StateMichigan
Coordinates44.35777, -84.61278
Functional classRural Minor Arterial

Condition and inspection

Good

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

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert8 Very GoodNo problems noted.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating81.8 US tons
Inventory rating62.8 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans1
Design loadGreater than HL 93
Structure length22 ft (6.7 m)
Longest span22 ft (6.7 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,550 (2017)
Projected traffic2,850 by 2040
Trucks4%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed—
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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$16,000 (2050 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was M-18 over Backus Creek built?

It was built in 2019, making it 6 years old in 2025.

What condition is M-18 over Backus Creek 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 July 2024.

How much traffic does M-18 over Backus Creek carry?

About 2,550 vehicles per day (2017 count), of which roughly 4% are trucks.

How long is M-18 over Backus Creek?

The structure is 22 ft (6.7 m) long with a longest span of 22 ft (6.7 m).

Who owns M-18 over Backus Creek?

It is owned by the State Highway Agency.