US Bridges

M-21 WB over I-96 EB Ramp

Fair

Kent County, Michigan · 0.2 MI E of Grand Rapids · Structure no. 000000000004740

Built
1961
64 years old
Condition
Fair
inspected June 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
219 ft
3 main spans
Daily traffic
5,413
2007 count
Owner
State
State Highway Agency

About this bridge

M-21 WB over I-96 EB Ramp is a steel stringer/multi-beam or girder carrying M-21 WB over I-96 EB Ramp in Kent County, Michigan. It was built in 1961, so it is 64 years old, older than the Michigan average of 48.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 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 5,413 vehicles a day, roughly 3% of them trucks, projected to reach 6,780 by 2018. The structure is 219 ft (66.7 m) long and 37 ft wide.

Location

Open in Google Maps
CarriesM-21 WB
CrossesI-96 EB Ramp
Location0.2 MI E of Grand Rapids
RouteState Highway 21
CountyKent County
StateMichigan
Coordinates42.96294, -85.58113
Functional classUrban Other Principal 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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating85 US tons
Inventory rating50.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20 + Mod
Structure length219 ft (66.7 m)
Longest span78 ft (23.7 m)
Deck width37 ft (11.2 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5,413 (2007)
Projected traffic6,780 by 2018
Trucks3%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed—
TollOn a free road
National Highway SystemYes

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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was M-21 WB over I-96 EB Ramp built?

It was built in 1961, making it 64 years old in 2025.

What condition is M-21 WB over I-96 EB Ramp 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 June 2024.

How much traffic does M-21 WB over I-96 EB Ramp carry?

About 5,413 vehicles per day (2007 count), of which roughly 3% are trucks.

How long is M-21 WB over I-96 EB Ramp?

The structure is 219 ft (66.7 m) long with a longest span of 78 ft (23.7 m) and a deck 37 ft wide.

Who owns M-21 WB over I-96 EB Ramp?

It is owned by the State Highway Agency.