Baltimore Grand Prix

This is a view of Grand Prix preparation construction on Conway Street between Charles and Light streets. (Barbara Haddock Taylor, Baltimore Sun / June 6, 2011)

Imagine the crowds that attend Artscape and the city marathon. Add the throngs drawn by Barack Obama's pre-inaugural visit. Mix in a few ethnic festivals and a bunch of holiday parades, and you get a sense of the transportation tangle Baltimore faces when open-wheeled racing comes to town.

The city's first venture into Indy car street racing — to run for three days beginning Friday — will tie up traffic for much of a week and disrupt transit patterns for at least five days when the Baltimore Grand Prix turns some of the busiest downtown thoroughfares into a racetrack.

Though officials have been planning for the race for months and say they can hold hassles to a minimum, they also say the Grand Prix has been one of the most complicated events ever held in Baltimore. City and Maryland Transit Administration officials emphasize their experience with events that require multiple street closings. Every summer, for example, they cope with Artscape, which blocks off some streets for more than a week — and involves moving light rail trains through the thick of the crowd.

The Grand Prix "will be the best-planned event we've ever had," said Frank Murphy, the city's deputy director of transportation.

The racing event brings some entirely new challenges. In addition to road closures, the race will sever the light rail line between South Baltimore and downtown. It also will cut in half eight MTA bus routes and one run by the city. Shuttle buses will serve the areas in between.

The Grand Prix has required the involvement of such agencies as the Maryland Transportation Authority, which controls Interstate 395 leading into downtown, and the Federal Highway Administration, which had to give permission to city and state officials to close part of the interstate highway system during the event.

While the Grand Prix itself is scheduled to run Friday through Sunday — unless bad weather forces a fourth day — it will also impede traffic flow while the race course is set up the preceding Thursday and broken down the following Monday.

City officials say that even if rain forces the event to spill over into Labor Day morning, all major intersections will be open and mass transit will be restored in time for the morning commute on Tuesday, Sept. 6.

Drivers in Baltimore will begin to feel the effects of the Grand Prix on Monday night, when a few small streets near Pratt will close. More will close Tuesday night, affecting the Wednesday commute, but the most serious disruptions won't begin until Thursday, officials say.

That day and Friday will be the most difficult for workers in and around downtown who haven't managed to get the days off.

Some of the city's main streets will be closed in the Camden Yards-Inner Harbor area, including Pratt, Light, Conway and Russell. Interstate 395 will be open through midday Thursday, but it will be closed before the evening rush hour that day and will remain shut until the event is over.

With I-395 and Light Street closed for much of the extended weekend, the main north-south route into the city will be Martin Luther King Boulevard. City officials acknowledged that route could become seriously congested and urged drivers to venture farther afield to avoid central Baltimore.

Specific suggestions can be found at the Grand Prix website, http://www.gptraffic.com. Murphy mentioned such routes as Caton Avenue, Hilton Parkway and Franklin/Mulberry on the west side or Washington and Wolfe streets on the east.

For many who use public transportation, the Grand Prix will bring significant disruption.

The city's two Charm City Circulator routes will be affected. The north-south Purple Route will be split in two by the race, which will close Light Street at Pratt. A southern portion will circulate around Federal Hill and Sharp-Leadenhall. The northern part will run from Penn Station to Redwood Street.

The eastbound part of the Orange Route loop will shift from Pratt Street to Baltimore Street. Travelers going from downtown to Federal Hill can walk along the Inner Harbor promenade.

The light rail line between Baltimore-Washington International Thurgood Marshall Airport and downtown will be split in two because the race course crosses the line at Camden Yards.

Northbound trains will end their run at Hamburg Street, near M&T Bank Stadium, while southbound trains will end at Baltimore Street. Riders who want to travel the full length of the route can take a shuttle bus that will ferry them from Baltimore Street to Hamburg via Martin Luther King Boulevard.

MTA spokesman Terry Owens acknowledged the transfer to the "bus bridge" would add time to the trip.