Construction is planned to start at 6 p.m. and will last for a week as the city prepares to host one of professional cycling’s most visible events.

The work will begin at East Broad and North Fifth streets and spread out across the city and region at a rate of about 4 miles per day. East Broad between Third and Seventh streets will be closed beginning tonight.

“They’ve timed the build-out at the exact pace necessary to have it complete as the event begins,” said Paul Shanks, director of communications and digital marketing at Richmond 2015, the group organizing the races.

The idea behind the timing of the work is to reduce the impact and leave as many roads open as possible and to minimize the disruption to the public ahead of the races.

The world championships, which begin with the opening ceremonies next Friday, are expected to draw 450,000 spectators over nine days and 300 million television viewers worldwide.

In addition to the spectators, about 1,000 cyclists from more than 60 countries as well as journalists and cycling officials from around the world are expected.

The event, Sept. 19 to 27, is forecast to create $158.1 million in economic impact for the state, with visitors spending $129.2 million in the region during the event.

The construction beginning today will transform a chunk of downtown Richmond into an Olympic-style village once the racing has begun.

Along the front of the Greater Richmond Convention Center, crews will build the main staging area for the races, with grandstands and broadcast booths.

One of the items to be built is the Markel VIP Pavilion, a 528-foot-long by 41-foot-wide elevated platform along Broad Street between Fifth and Seventh streets adjacent to the finish line.

Work on the pavilion will take about a week.

City crews will remove traffic signals and light poles and pave a stretch of road right around the finish line to accommodate the staging area and pavilion.

The target date to reopen the stretch of Broad Street is Oct. 1.

As the construction begins, city crews will continue focusing on last-minute work at sites such as Libby Hill, Jefferson and Monroe parks, as well as finishing paving projects around the course, trimming trees and cutting grass.