U.S. federal and local authorities are gearing up to meet the challenge of massive wave of inaugural-goers on Jan. 20, when Barack Obama is inaugurated as U.S. President, CNN reported Wednesday.

Authorities are struggling to achieve an almost impossible balance, encouraging people to participate on the one hand while warning potential participants that the crush could be overwhelming.

At a control center in northern Virginia close to Washington D.C., officials will monitor traffic for the area, and they are bracing for a couple of very difficult days.

An elaborate transportation plan will ban private cars from two major routes into the capital city and all the bridges from Virginia to Washington.

Members of the U.S. military line the street during a rehearsal of the upcoming parade to celebrate the inauguration of U.S. President-elect Barack Obama in Washington January 11, 2009
For security reasons, a big swath of downtown Washington will be closed to cars.

On Tuesday, President George W. Bush declared that an "emergency exists in the District of Columbia" from January 17-21 and ordered that federal aid go to supplement the city's response efforts, according to the White House.

Funds will be used for emergency protective measures related to the inauguration.

The city of Washington has received 15 million U.S. dollars in federal funding for inauguration activities.

Another part of the transportation plan is how to get people out of the city.

People should not venture into Washington on Inauguration Day without a travel plan, said Martin O'Malley, governor of Maryland close to Washington D.C..

Authorities have rolled back early estimates of 4 million visitors but say that even half that number will result in traffic jams and disappointed people being turned away from the parade route.

Officials said it will be impossible for people who are attending the swearing-in ceremony in the morning to also witness the inaugural parade in the afternoon, even though the events are just blocks away.

The parade route is expected to fill up even before the swearing-in starts.

Once the route, which can accommodate 300,000 to 350,000 people, is filled, people will be turned away.

The relief valve will be the huge National Mall, where hundreds of thousands can congregate and witness both the swearing-in and parade on more than 20 JumboTrons TVs.

The U.S. Secret Service, the Department of Homeland Security and local jurisdictions are working on a comprehensive plan to deal with the possibility that people on the Mall may have to be evacuated.

Source:Xinhua