Transportation Data and Analysis

Here you will find data and maps on things like transportation projects, traffic volumes, condition ratings for bridges, and other data as we gather it.

National Highway System (NHS) Bridge Condition Data for Michigan MPOs

National Highway System (NHS) bridge condition ratings as of January 2023 for all Michigan MPOs.

The National Bridge Inventory (NBI) is a database maintained by the Federal Highway Administration (FHWA) that contains information on all bridges on public roads in the United States. The NBI includes details such as the location, size, type, condition, and weight capacity of each bridge, as well as the year it was built, its owner, and any recent inspections. The purpose of the NBI is to provide state and local transportation agencies with the information they need to prioritize and allocate resources for bridge maintenance and replacement, and to help the public make informed decisions about travel. The NBI is updated annually and is available to the public through the FHWA's website.

The National Highway System (NHS) is defined by law in the United States as a network of highways that are important to the nation's economy, defense, and mobility. The legal definition of the NHS is set forth in Title 23, United States Code, Section 103 (c).

According to the act, the NHS consists of:

  1. The Dwight D. Eisenhower National System of Interstate and Defense Highways, which includes the entire interstate highway system.

  2. Other principal arterials that connect major cities, urban centers, and rural communities and serve national defense, economic, and mobility needs.

  3. Strategic highways that connect major military installations, ports, airports, and other strategic transportation facilities.

The purpose of the NHS is to provide an efficient and effective national transportation system that can support the movement of people and goods, enhance economic competitiveness, and enhance national security.

The NHS is eligible for federal funding under the Federal-Aid Highway Program, which provides financial assistance for the construction, improvement, and preservation of highways and bridges in the United States.