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
|Daily Crossings on All Bridges||Number of Structurally Deficient Bridges||Area of Structurally Deficient Bridges
|Daily Crossings on Structurally Deficient Bridges|
|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 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 local road||591||324,510||2,949,852||54||20,215||194,425|
Proposed Bridge Work
|Type of Work||Number of Bridges||Cost to Repair
|Daily Crossings||Area of Bridges
|Widening & rehabilitation||76||$34.5||1,306,239||43,688|
|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.