The Interstate Highway System: What Worked, What Did Not

It's been 50 years since President Eisenhower signed the bill creating the Interstate Highway System, one of the most successful federal programs ever. Randal O'Toole offers a few indicators of the success of the Interstate Highway System.

1 minute read

July 6, 2006, 1:00 PM PDT

By Chris Steins @planetizen


Among the indicators:

  • Interstate highways make up less than 1.2 percent of the mileage of all roads in the U.S., yet they carry nearly half of all heavy truck traffic and nearly a quarter of all passenger traffic.
  • Since the Interstate Highway System was created, per capita miles of driving have tripled without any increase in the share of personal incomes spent on driving.
  • When combined with freight containers -- which, coincidentally, were also developed in 1956 (or 1955, depending on which history you read) -- the Interstate Highway System greatly contributed to the 90-percent reduction in shipping costs during the twentieth century.

    "...When Congress was debating the Federal-Aid Highway Act in 1955, engineers estimated they could build the entire system in twelve years for $23 billion. In fact, the system was not declared complete until thirty-five years later at a total cost of $129 billion. Even today, some short sections remained unfinished.

    After the system was more-or-less complete, the money kept pouring in. With no firm goal for the money, it might not be surprising that Congress turned highway funds into pork. The truth is a bit more subtle and involves the transfer of policy-making and planning power from engineers to urban planners. One reason for this transfer was the inflation of the 1960s and 1970s."

    Thanks to Randal O'Toole

  • Wednesday, July 5, 2006 in The Thoreau Institute

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