US Bridges

M-21 over Rush Creek

Good

Shiawassee County, Michigan · 2.8 MI W of Genesee Col · Structure no. 000000000009777

Built
2022
3 years old
Condition
Good
inspected July 2023
Type
Culvert
Concrete
Length
34 ft
1 main span
Daily traffic
9,700
2018 count
Owner
State
State Highway Agency

About this bridge

M-21 over Rush Creek is a concrete culvert carrying M-21 over Rush Creek in Shiawassee County, Michigan. It was built in 2022, so it is 3 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 9,700 vehicles a day, roughly 10% of them trucks, projected to reach 11,155 by 2038. The structure is 34 ft (10.3 m) long.

Location

Open in Google Maps
CarriesM-21
CrossesRush Creek
Location2.8 MI W of Genesee Col
RouteState Highway 21
CountyShiawassee County
StateMichigan
Coordinates42.99954, -83.98659
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 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating63.6 US tons
Inventory rating48.9 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans1
Design loadGreater than HL 93
Structure length34 ft (10.3 m)
Longest span34 ft (10.3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic9,700 (2018)
Projected traffic11,155 by 2038
Trucks10%
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$27,000 (2050 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was M-21 over Rush Creek built?

It was built in 2022, making it 3 years old in 2025.

What condition is M-21 over Rush 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 2023.

How much traffic does M-21 over Rush Creek carry?

About 9,700 vehicles per day (2018 count), of which roughly 10% are trucks.

How long is M-21 over Rush Creek?

The structure is 34 ft (10.3 m) long with a longest span of 34 ft (10.3 m).

Who owns M-21 over Rush Creek?

It is owned by the State Highway Agency.