Formed: June 29, 1956 | Interstates: Interstate nn (I-nn) | |
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Length: 1,572.35 mi (2,530.45 km) Business Loops: Business Loop Interstate nn (BL I-nn) | ||
There are a total of 21 Interstate Highways in Ohio, including both primary and auxiliary routes. All of the Interstate Highwayss are owned and maintained by the U.S. state of Ohio through the Ohio Department of Transportation (ODOT); however, they were all built with money from the U.S. federal government. The road miles of these 21 Interstates add up to a total of 1,572.35 miles (2,530.45 km). Ohio has more route miles than this, most of which comes from Interstate 80 (I-80) running concurrently with I-90 for 142.80 miles (229.81 km). The Interstate Highways in Ohio range in length from I-71, at 248.15 miles (399.36 km), all the way down to I-471, at 0.73 miles (1.17 km).
As of 2006, out of all the states, Ohio has the fourth-largest Interstate Highway System. Ohio also has the fifth-largest traffic volume and the third-largest quantity of truck traffic. Ohio ranks second in the nation in terms of the number of bridges for its Interstates.
History
On June 29, 1956, President Dwight D. Eisenhower signed the Federal Aid Highway Act of 1956, which called for the construction of up to 41,000 miles (66,000 km) of Interstate Highways. Of that, up to 1,500 miles (2,400 km) were to be built in Ohio. The same year, Ohio passed a law which raised the state's speed limit to 60 mph (97 km/h), and in 1957, Ohio began the construction of its Interstate Highway allotment. By 1958, Ohio had spent more money on its Interstate Highways than either New York or California. In 1960, Ohio had completed the construction of 522 miles (840 km) of pavement; in 1962, Ohio had completed the construction of 684 miles (1,101 km) of pavement; and in 1970, Ohio had completed the construction of 1,000 miles (1,600 km) of pavement. By the end of 1971, Ohio had only 167 miles (269 km) of Interstate still to build. On September 19, 2003, Ohio finally finished the originally planned Interstate Highway System.