According to the Federal Highway Administration, the Interstate System consists of routes of highest importance to the
nation. The highways connect principal metropolitan areas, cities and industrial
centers and are built to uniform geometric and construction standards.
The system also serves the national defense and connects with routes of continental importance in Canada and Mexico. Roadways with interstate designation have the highest priority among the functional classes of highways in terms of maintenance and safety.
Wisconsin's Interstate highway designations
Currently, Wisconsin has four designated Interstate highways: I-39, I-43, I-90 and I-94. The most recent designation occurred in 1996, when I-39 was designated from the Wisconsin state line near Rockford, Illinois, north to Wausau (along much of US 51).
Wisconsin first proposed the designation of I-39 in 1991, with the request approved by the U.S. DOT in 1992. Following approval, there were key steps to complete the designation:
The change required significant capital investment to upgrade interchanges and bridge clearances to Interstate highway standards.
Congress exempted the route from certain federal weight limit requirements in 1995 to allow trucks over 80,000 pounds.
From 1995 to 1997, WisDOT spent about $1 million to upgrade signs and install new Interstate highway shields along the route.
Interstate highways and economic development
Many businesses saw the designation of I-39 as a major boost to economic development and commerce. The change literally put the highway and certain communities on the map from a national perspective, and aided in marketing central Wisconsin products and businesses. Local planning efforts have incorporated many of the economic development initiatives near the access points along the interstate highways. Studies have revealed that development has occurred at major interchanges along the interstate highways depending upon its proximity to urban centers and availability of essential utility services needed for development.
The potential exists for other communities or regions to seek Interstate highway designations to pursue similar economic benefits. A likely possibility is the US 45/US 41 corridor from Milwaukee to Green Bay. WisDOT recently upgraded the entire corridor to a freeway, and the route serves several population and employment centers, including Appleton, Oshkosh, and Fond du Lac.