If a major disaster hits the Twin Cities, people should walk, not drive, to the nearest safe zone, according to the official evacuation plan developed by state officials.

For the first time Wednesday, two of the key people who worked on the plan talked about it publicly even though it was completed in late December. The disasters they envisioned were all man-made, ranging from an airborne anthrax release to a chlorine tank rupture, said Daryl Taavola, who works for a transportation engineering company, URS Corp., and was hired to work with the Minnesota Department of Transportation on the evacuation plans.

The Minnesota Army National Guard's 55th Civil Support Team recommended that only people within a one-mile radius of the disaster be evacuated, he said.

"We would encourage people to walk to pickup points in safe zones,'' Taavola told an audience at the Intelligent Transportation Systems meeting in Minneapolis. "We will get you out of harm's way, but we can't guarantee we will get you home right away.''

Instead, people would be transported by Metro Transit or school buses from the pickup points to large gathering areas, such as the Minnesota State Fairgrounds, where they could get water, use bathroom facilities and call their loved ones, he said.

University of Minnesota professor Shashi Shekhar ran computer models of evacuation routes and found that because of the time people took to get to their cars and then the traffic jams created, leaving the car behind was the best option.

"For a one-mile evacuation, almost always the pedestrian is faster than the vehicle,'' he said.

They even considered locking down the parking ramps so people could not leave by car but decided against it because of liability issues, Taavola said. The other problem with cars is that a family of four with four drivers will have each one jump into a family car and head out as a caravan because the cars "are such a big investment,'' said Scott Alley, who saw that problem firsthand as a Texas Department of Transportation official during the Hurricane Rita evacuation. That many cars clog the roads even quicker, he said.

Because walking rather than driving contradicts the natural instincts of most people, there will have to be public education before a disaster, Taavola said.

The evacuation plan "is a big thing, multi-agency, with lots of moving parts, and we will get that out at some point,'' said transportation department spokesman Kevin Gutknecht. He did not know when that public education would begin.

The transportation department spearheaded the Twin Cities metropolitan area evacuation plan in January 2004. At first, they and dozens of other state and local agencies looked at 15 sites in the Twin Cities where a disaster was likely to occur. They eventually narrowed it to downtowns St. Paul and Minneapolis, the University of Minnesota, Mall of America and one of the oil refineries south of St. Paul, Taavola and Shekhar said.

Under the plan, transportation department trucks or police cars would be parked across a street lane or a freeway ramp to prevent people from driving toward the disaster, and force them to make only right turns, Taavola said. Minnesota State Patrol troopers would secure the routes to the hospitals so ambulances could move freely, he added.

Assuming electrical systems are working, the electronic signboards on the freeways would flash evacuation messages. The traffic and jazz radio station, KBEM-FM, would switch to providing emergency information, and the news media would be informed, although Taavola admitted there was still "lots of outreach to be done."

They also decided against contraflowing, which is making all lanes of the freeway go the same direction as they do in hurricane evacuations, Taavola said. More planning needs to be done, he added, including how to reach non-English speaking people in the disaster zone and working with building managers on what to tell tenants if there is a need to evacuate, he said.

Charles Laszewski can be reached at claszewski@pioneerpress.com or 651-228-5458.