Ban on Lone Drivers at Some New York Gates

Mayor Rudolph W. Giuliani said yesterday that the police would bar cars carrying only one person from crossing into Midtown and Lower Manhattan on weekday mornings, starting tomorrow, a response to crushing traffic jams that have spread for miles as a result of security checkpoints.

The decision -- which city transportation officials had been urging the mayor to make for the last week -- was an indication of just how bad traffic across the metropolitan region has become since the attack on the World Trade Center, causing cars and trucks from gridlocked highways to spill back onto local roads as far away as Nassau County and many miles into New Jersey, long after regular rush-hour jams usually abate.

The traffic jams have been caused, in part, by bridge and tunnel closings and the cordoning off of Lower Manhattan. But the heightened security at nearly every crossing into the city is the main factor causing the gridlock. And yesterday -- as Attorney General John Ashcroft warned in Washington that there was a ''clear and present danger'' of additional terrorist attacks that could include trucks carrying hazardous chemicals -- the checks were made much stricter.

Asked yesterday if the security checkpoints around the city were the result of a specific or credible threat, Mr. Giuliani said no, but added that ''we're more sensitive to threats that are received that -- maybe six months ago or, not even six months ago, three weeks ago -- you would have said: 'There's another nut that's calling.' ''

The result of the heightened security, all day, everywhere around the city, was a system almost at the breaking point, even delaying the Yankees game by half an hour last night because fans could not get to Yankee Stadium.

''Traffic today was frankly the worst that many at Transportation had seen in recent memory,'' said Tom Cocola, a spokesman for the city's Department of Transportation. ''It was hell. All the arteries were clogged because of the checkpoints, and the rain didn't help either. It was bad.''

City officials said the ban would apply to cars entering Manhattan south of 62nd Street between 6 a.m. and noon weekdays on all the East River bridges that the city controls. The city also expects the cooperation of the Port Authority of New York and New Jersey, which operates the Lincoln Tunnel, and the Triborough Bridge and Tunnel Authority, which operates the Queens-Midtown Tunnel, in placing the same restrictions at those crossings.

The bridge and tunnel agency, a part of the Metropolitan Transportation Authority, which also runs the subways and buses, was said yesterday to favor the idea. That is in part because the subways have been carrying only about 80 to 85 percent of their regular ridership since the Sept. 11 attacks, a decline that should be addressed, Mr. Giuliani said yesterday.

City officials said that on an average weekday, roughly two-thirds of the vehicles in Manhattan south of 96th Street are single-occupancy vehicles.

They said the ban would not apply to cars with Taxi and Limousine Commission license plates, meaning medallion and livery cabs and limousines based in New York City. It would also not apply to any vehicles with commercial license plates, even to vans or cars with such plates whose drivers are conducting business or carrying goods into the city. And people who live in Manhattan could take their cars on the streets without passengers, officials said, but if they left the island and tried to return, they could be prevented from doing so during the restricted hours.

''If you're a delivery guy, clearly we want you to get into the city without as much of a problem,'' a senior city official said.

But the remedy announced by the mayor raised a long list of logistical questions that city officials were unable to answer yesterday. How and where would single-occupancy vehicles be stopped? Would they be turned around, on already gridlocked highways, or just ticketed?

''Those are things we are trying to work out right now,'' a city official said.

Officials said the ban would be the first time in more than 20 years that such restrictions had been placed on cars entering Manhattan. During a subway strike in 1980, when added vehicular traffic created scenes of gridlock similar to those now, single-occupant cars were temporarily barred from entering south of 96th Street during the morning rush hour.

Since the World Trade Center attack, the police have set up checkpoints at most of the crossings into the city and are stopping many vehicles to make sure they are not carrying explosives or other dangerous cargo.

Inspections were being made mostly of buses and trucks, not cars, because security experts believe that a car could not carry enough explosives to cripple a bridge or tunnel, according to one police official.

Yesterday, those checkpoints appeared to become much stricter and drivers reported that even private minivans carrying families and children were being pulled over and examined near bridges and tunnels. The checks, coupled with a handful of accidents and other delays caused by construction, caused traffic to back up for miles into Queens and Brooklyn from as early as 5:30 a.m. until after noon.

One man described how a normal half-hour commute from the Queens-Nassau County border to the Midtown Tunnel had turned into a two-hour crawl yesterday.

A city official warned drivers not to expect much better:''It's not going to go back to the way it was in the foreseeable future.''