Michigan’s bridges are in rough shape. Nearly every expert agrees the main culprit is lack of funding.

The American Road & Transportation Builders Association released the 2017 National Bridge Inventory data base, which analyzes the nation’s bridges. Below are the key findings for Michigan.

  • Of the 11,180 bridges in the state, 1,175, or 10.5 percent, are classified as structurally deficient. This means one of the key elements is in poor or worse condition.1
  • 63 structurally deficient bridges in the state are on the Interstate Highway System.
  • 1,086 bridges are posted for load, which may restrict the size and weight of vehicles crossing the structure.
  • Over the last five years, bridge investment has accounted for 22.4 percent of highway and bridge contract awards in the state, compared to an average of 28.9 percent nationwide.2
  • Over the last 10 years, 952 new bridges have been constructed in the state; 548 have undergone major reconstruction.
  • The state has identified needed repairs on 1,736 bridges; which the state estimates will cost $9.2 billion.3

Top Most Traveled Structurally Deficient Bridges in Michigan

County Year Built Daily Crossings Type of Bridge4 Location
Wayne 1954 146,000 Urban minor arterial Second Blvd over I-94
Wayne 1963 114,656 Urban freeway/expressway M-39 over Rouge River
Wayne 1967 100,492 Urban Interstate I-75 over Rouge R,Dearborn St & RR
Wayne 1967 100,492 Urban Interstate I-75 over Fort St
Kalamazoo 1956 69,260 Urban Interstate I-94 over Portage Road
Wayne 1969 68,056 Urban other principal arterial M-102 8 mile Rd over I-75
Oakland 1964 65,985 Urban Interstate I-75 SB over M-150 (Rochester Rd.)
Wayne 1962 65,737 Urban Interstate I-94 WB over Ecorse Rd
Jackson 1949 64,800 Urban Interstate I-94 over Conrail & Grand River
Wayne 1967 63,820 Urban other principal arterial US-24 Telegraph Rd over Rouge River
Genesee 1976 63,400 Urban Interstate I-475 over Stever – Broadway Aves
Saginaw 1961 60,342 Urban Interstate I-75 over CSX RR
Wayne 1962 55,956 Urban Interstate I-94 WB over Wayne Rd
Ottawa 1960 54,922 Urban other principal arterial US-31 over Grand River, M-104 Conn
Wayne 1953 54,800 Urban Interstate I-94EB Rmp to M-10 over I-94 WB & M-10 SB
Jackson 1949 54,000 Urban local road Elm Rd over I-94
Wayne 1964 51,090 Urban Interstate I-75 SB over Blakely Drain
Wayne 1964 51,090 Urban Interstate I-75 NB over Blakely Drain
Wayne 1966 50,643 Urban Interstate I-75 SB over North Line Rd
Wayne 1966 47,466 Urban Interstate I-75 SB over Eureka Rd
Wayne 1966 47,466 Urban Interstate I-75 NB over Eureka Rd
Wayne 1962 42,800 Urban minor arterial Jefferson Ave over I-375
Wayne 1964 41,706 Urban Interstate I-75 SB over US-24 Conn
Wayne 1966 40,500 Urban Interstate I-75 NB over Goddard Rd, Sxtn-Kil Drn
Genesee 1970 40,030 Urban Interstate I-69 EB over Hammerberg Road


Bridge Inventory Michigan

Type of Bridge4 Number of Bridges Area of All Bridges
(sq. meters)
Daily Crossings on All Bridges Number of Structurally Deficient Bridges Area of Structurally Deficient Bridges
(sq. meters)
Daily Crossings on Structurally Deficient Bridges
Rural Interstate 401 365,719 7,908,816 12 6,797 247,014
Rural arterial 637 410,305 5,642,667 22 8,419 114,182
Rural minor arterial 610 292,575 3,143,955 39 19,436 165,666
Rural major collector 2,089 671,731 4,420,563 279 61,602 537,350
Rural minor collector 544 131,154 1,099,448 64 10,347 33,121
Rural local road 3,162 544,269 1,556,108 489 51,035 127,827
Urban Interstate 829 1,391,264 29,855,289 51 198,430 1,805,107
Urban freeway/expressway 319 334,778 8,367,754 10 11,042 308,278
Urban other principal arterial 712 875,460 15,648,018 48 104,552 1,004,606
Urban minor arterial 811 739,387 9,717,303 73 40,843 900,386
Urban collector 475 287,454 3,417,785 34 18,910 156,111
Urban local road 591 324,510 2,949,852 54 20,215 194,425
Total 11,180 6,368,612 93,727,558 1,175 551,633 5,594,073

Proposed Bridge Work

Type of Work Number of Bridges Cost to Repair
(in millions)
Daily Crossings Area of Bridges
(sq. meters)
Bridge replacement 678 $5,755.1 1,985,960 141,019
Widening & rehabilitation 76 $34.5 1,306,239 43,688
Rehabilitation 169 $1,844.1 691,490 78,166
Deck rehabilitation/replacement 774 $1,644.3 9,712,315 750,527
Other structural work 39 $0.3 3,935 3,396
  • 1According to the Federal Highway Administration (FHWA), a bridge is classified as structurally deficient if the condition rating for the deck, superstructure, substructure or culvert and retaining walls is rated 4 or below or if the bridge receives an appraisal rating of 2 or less for structural condition or waterway adequacy. During inspections, the condition of a variety of bridge elements are rated on a scale of 0 (failed condition) to 9 (excellent condition). A rating of 4 is considered “poor” condition and the individual element displays signs of advanced section loss, deterioration, spalling or scour. ARTBA follows the methodology of the FHWA and evaluates bridge status without applying the 10-year rule.
  • 2ARTBA analysis of Dodge Data Analytics data.
  • 3States report the cost of proposed bridge work for each bridge to the Federal Highway Administration as part of the bridge inventory data each year. Each highway agency is encouraged to use its best available information and established procedures to determine bridge improvement costs.
  • 4Bridges are classified by FHWA into types based on the functional classification of the roadway on the bridge. Interstates comprise routes officially designated by the Secretary of Transportation, and the Dwight D. Eisenhower National System of Interstate and Defense Highways. Other principal arterials serve major centers of urban areas or provide mobility through rural areas. Freeways and expressways are similar to interstates, with directional lanes generally separated by a physical barrier, and access/egress points generally limited to on- and off-ramps. Minor arterials are used for trips of moderate length, serve smaller geographic areas and connect to the higher arterial system. Collectors funnel traffic from local roads to the arterial network; major collectors have higher speed limits and traffic volumes, and are longer in length and spaced at greater intervals, while minor collectors are shorter and provide service to smaller communities. Local roads do not carry through traffic, and are intended for short distance travel.
  • Source: Bridge data is from the 2017 National Bridge Inventory ASCII files, released by the Federal Highway Administration in January, 18 2018. Note that specific conditions on bridges may have changed as a result of recent work.