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Broad, open and breezy as the superhighway may be out in the country, it often hits trouble at the city limits. The name of the trouble is "downtown." Where cities prize the idea of a distinct center, or where they are locked into it by topography, as in New York City or San Francisco, the congestion of building at the center vastly increases the difficulty of applying the principles—divided lanes, cloverleafs —of the expressway. Where cities have ample room and are indifferent to the idea of "downtown," expressways can be shaped in belts, loops and spokelike patterns that solve most traffic problems. Houston is one such city, and it smugly considers its traffic headaches to be negligible.
In truly congested cities, the expanses of concrete built to unclog traffic are often jammed almost from the moment they open. The Long Island Expressway, designed for 80,000 by 1970, now carries up to 170,000 a day; and the Hollywood Freeway, intended for 120,000 by 1970, now conveys nearly twice that many. "This is the only business where, if you have record crowds the first day, you consider it a failure," says Chicago's Project Supervisor Patrick J. Athol. To technophobes, this proves the futility of building roads—but that is something like not building schools to keep children from being born.
The traffic-jam trauma is under attack. For example, Detroit's John C. Lodge Expressway is testing an ingenious control system. Fourteen TV cameras, mounted on bridges over a particularly congested three-mile stretch, transmit pictures of cars to a 14-screen big-brother console near by. Technicians at the console can zoom in their lenses for closeup shots of any single suspicious vehicle; on several occasions they have watched on television while a smashup or a breakdown occurs. Then they call a policeman and throw switches that change speed-limit signs, block ramps, and turn on big red X signs over the lane that is blocked.
Even without such futuristic paraphernalia, city traffic in most places is moving better than it ever has. Driving time from one distant suburb into downtown Houston averaged 26.7 minutes during peak hours in 1960, now takes just 17.7 minutes. Los Angeles has a last laugh too: in 1957 a survey showed that peak-hour speeds on all freeways and streets averaged 24 m.p.h.; last year the average was up to 31 m.p.h.—not grand prix, but better than most mass transit.
Meanwhile New York, bastion of the crawling car and the double-parked truck, is only coping. Traffic Commissioner Henry A. Barnes has seen to it that Manhattan's major north-south streets are going—or will go—one way, and traffic has speeded up about 30%. Last week Barnes finally got permission to begin installing a $100 million system of traffic lights that will get their cues from what sensor-sent messages tell a computer about the flow of traffic.