June 29 marked fifty years since President Eisenhower signed the bill creating the Interstate Highway System, one of the most successful federal programs ever. Interstates opened up the country to the average family who could not afford plane or train fares; they enabled rapid, low-cost movement of freight; and they greatly increased highway safety. But they also took far longer to complete than originally projected and many of the routes, particularly in cities, were subject to acrimonious conflict.
When Congress passed the Federal-Aid Highway Act in 1956, engineers estimated they could build the entire system in twelve years for $25 billion. In fact, the system was not declared complete until thirty-five years later at a total cost of $114 billion.
Three factors made the Interstate Highway System work: decentralization, the engineering mindset, and incentives. Although it was a federal program, the Interstate Highway System was actually planned, designed, built, and maintained by state highway departments. The Bureau of Public Roads -- later the Federal Highway Administration -- enforced minimum standards, such as lane width and curvature -- most of which had been developed by the state engineers -- but otherwise was really little more than a pass-through funding agency.
