SEMCOG | Southeast Michigan Council of Governments

About this Map

SEMCOG’s interactive Road Jurisdiction Map shows jurisdictional ownership, National Highway System (NHS), and National Functional Classification (NFC) of roads that make up the Southeast Michigan transportation network.

Jurisdiction information includes whether the road is under state, county, city and village, or private ownership. Jurisdiction is based on the Act 51 designation of the road as attributed in the Michigan Geographic Framework base map. Roads under state jurisdiction are owned by the Michigan Department of Transportation, and include all ‘I-‘, ‘US-‘, and ‘M-‘ routes in the region. County, city, or village roads are owned by the respective communities in which they are located. Under Michigan law, townships do not have jurisdiction of roads. Those roads are under the jurisdiction of the county.

The National Functional Classification is a federal designation based on the type and characteristics of traffic carried on the particular roadway. For example, the interstate system has high mobility, whereas local roads are generally low-speed roads with high access to housing, commercial, or other types of land use. The NFC is also used to determine the funding eligibility for certain federal highway programs. NFC designations are Interstate, Other Freeway, Other Principal Arterial, Minor Arterial, Major Collector, Minor Collector, Local, and Uncertified Road.

Instructions

Hover over and click a road segment to learn more details about the road including Road Name, County, Community, NFC, System Status, and Contact. The top right corner of the map will show the percentage of road and centerline miles by jurisdiction for the roads in the map view screen. Individual counties and communities can also be selected.

Definitions

• Jurisdiction: Community responsible for maintaining road.
• National Highway System (NHS): The National Highway System is a network of strategic highways within the United States, including the Interstate Highway System and other roads serving major airports, ports, rail or truck terminals, railway stations, pipeline terminals, and other strategic transport facilities.
• National Functional Classification (NFC): Federal organizational system for all public roads.

Data from these maps are available via the SEMCOG Open Data Portal.

Please contact SEMCOG about any needed updates to the data or map.