SEMCOG 2022 Bridge Condition Data Now Available
Bridges are an essential part of our transportation system. Many of us cross bridges each day without even noticing, provided they are well-maintained. Maintenance, along with bridge-building and restoration when necessary, comprise a significant investment for Michigan Department of Transportation (MDOT) and local agencies. SEMCOG recently updated its Bridge Condition map (in the Map Gallery) to provide local officials and stakeholders with information about bridge conditions throughout the region.

MDOT maintains the data as part of their annual report of the National Bridge Inventory (NBI) of structures in the state. Bridges in good or fair condition are inspected at least once every 24 months. Bridges in poor condition are inspected at least once every 12 months.
The SEMCOG region has almost 3,000 structures in the National Bridge Inventory. Of those structures, 2,468 are bridges, and 526 are culverts. What is the difference? Bridges are structures that have a span of 20 feet or greater. Culverts are structures that span less than 20 feet. Of the region’s bridges, 12 % are currently rated in poor condition, as are 12% of culverts.
Historical Bridge Conditions, SEMCOG Region

Source: MDOT; TAMC
Over the last decade, distinct trends have emerged for bridges in the SEMCOG region. The total bridge deck area in poor condition dipped below 10% in 2018 and has hovered around 9 percent since then. Once bridges deteriorate to poor condition, they are incredibly expensive to rehabilitate or reconstruct.
The percentage of bridge deck area in good condition has dipped from 40.5% in 2016 to 32.5% now. The percentage of bridges in fair condition has increased over that time. MDOT and local agencies are employing asset management approaches to maintain bridges and maximize investments. Preventing bridges from reaching poor condition remains a key goal, and the Infrastructure Invest and Jobs Act (IIJA) has prioritized improving bridge conditions. System providers will attempt to maximize this opportunity in the coming years to bring as many of the region’s bridges up to good condition as possible while maximizing the lifespan of each bridge with asset management.
Pedestrian Bridges
For the first time, information on the condition 132 pedestrian bridges in the region is available from MDOT. Most of the pedestrian bridges provide critical route connections for people who walk over freeways or other high volume roads. This data will help to maintain and enhance vital links in the region’s non-motorized transportation network.
Pedestrian Bridges

How Do I Find Bridges in My Community?
The state’s bridge database is a large, complex dataset, and SEMCOG’s bridge map allows you to filter data to find those structures that are important to your community.
For example, you may want to find all bridges owned by the City of Dearborn. First, select Dearborn in the County/Community area in the map legend. This will display all bridges within the city.
Bridges in Dearborn

You may also want to know who is responsible for each bridge. In the Bridge Owner filter area, you have the option of selecting MDOT, County, or City/Other bridges. Selecting City/Other will bring up city-owned bridges within Dearborn.
City-Owned Bridges in Dearborn

Finally, clicking on a bridge icon will bring up detailed information about the structure. You can even click on the “Click here to comment on this bridge” to send an email to SEMCOG if you have specific questions about any structure.
Detailed Information

Funding Opportunities
The Infrastructure Invest and Jobs Act (IIJA) made $563 million available to Michigan over 5 years to replace or repair bridges. At least 25 percent of the money will go to local bridges. This program is being administered through MDOT’s Local Bridge Program.
In addition, the Federal Highway Administration’s (FHWA) competitive, discretionary Bridge Investment Program focuses on improving existing bridges to reduce the overall number of bridges in poor condition. This program will make $12.5 billion available over five years. Information and application information for this program is available here.
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