Construction of the US Interstate System
The Interstate Highway System was authorized by the Federal Aid Highway Act of 1956 – popularly known as the National Interstate and Defense Highways Act of 1956 – on June 29.
Three states have claimed the title of first Interstate Highway. Missouri claims that the first three contracts under the new program were signed in Missouri on August 2, 1956. The first contract signed was for U.S. 66. On August 13, 1956, Missouri awarded the first contract based on new Interstate Highway funding.
Kansas claims that it was the first to start paving after the act was signed. Preliminary construction had taken place before the act was signed, and paving started September 26, 1956. The state marked its portion of I-70 as the first project in the United States completed under the provisions of the new Federal-Aid Highway Act of 1956.
According to information liaison specialist, Richard Weingroff, the Pennsylvania Turnpike could also be considered one of the first Interstate Highways. On October 1, 1940, 162 miles (261 km) of the highway now designated I-70 and I-76 opened between Irwin and Carlisle. The Commonwealth of Pennsylvania refers to the turnpike as the Granddaddy of the Pikes.
Nebraska was the first state to complete its mainline Interstate Highway, finishing its section of Interstate 80 on October 19, 1974. The opening of I-70 through Glenwood Canyon in 1992 is often cited as the completion of the originally planned system. The initial cost estimate for the system was $25 billion over 12 years; it ended up costing $114 billion (adjusted for inflation, $425 billion in 2006 dollars) and took 35 years.
Posted by Dave at 10:00 AM