US Bridges

M-99 SB over Gtw RR & Grand River

Fair

Ingham County, Michigan · In Lansing (mlk Blvd) · Structure no. 000000000003691

Built
1975
50 years old
Condition
Fair
inspected July 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
1,167 ft
9 main spans
Daily traffic
16,460
2007 count
Owner
State
State Highway Agency

About this bridge

M-99 SB over Gtw RR & Grand River is a steel stringer/multi-beam or girder carrying M-99 SB over Gtw RR & Grand River in Ingham County, Michigan. It was built in 1975, so it is 50 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 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 16,460 vehicles a day, roughly 3% of them trucks, projected to reach 43,500 by 2028. The structure is 1,167 ft (355.7 m) long and 52 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesM-99 SB
CrossesGtw RR & Grand River
LocationIn Lansing (mlk Blvd)
RouteState Highway 99
CountyIngham County
StateMichigan
Coordinates42.71958, -84.56825
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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2024
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 geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating107.1 US tons
Inventory rating71.4 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans9
Design loadHS 25 or greater
Structure length1,167 ft (355.7 m)
Longest span180 ft (54.9 m)
Deck width52 ft (15.9 m)
Roadway width40 ft (12.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic16,460 (2007)
Projected traffic43,500 by 2028
Trucks3%
Lanes on structure3
Traffic directionOne-way traffic
CarriesHighway
CrossesRailroad and waterway
Detour if closed1.2 mi (2 km)
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 proposedDeck replacement with only incidental widening
Estimated improvement cost$793,000
NavigationNo navigation control on waterway

Frequently asked questions

When was M-99 SB over Gtw RR & Grand River built?

It was built in 1975, making it 50 years old in 2025.

What condition is M-99 SB over Gtw RR & Grand 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 July 2024.

How much traffic does M-99 SB over Gtw RR & Grand River carry?

About 16,460 vehicles per day (2007 count), of which roughly 3% are trucks.

How long is M-99 SB over Gtw RR & Grand River?

The structure is 1,167 ft (355.7 m) long with a longest span of 180 ft (54.9 m) and a deck 52 ft wide.

Who owns M-99 SB over Gtw RR & Grand River?

It is owned by the State Highway Agency.