Crews will take down the barricades and detour signs and open bridges on Lyndale and Plymouth Avenues in Minneapolis to traffic this afternoon.

A little fanfare will surround the opening of the Lyndale Avenue Bridge over Minnehaha Creek as city and county officials, business owners and residents mark the occasion with a ribbon cutting at 1 p.m. at the Washburn Library at 5244 Lyndale Av. S.

About an hour later, the "Road Closed" signs will come down on the Plymouth Avenue Bridge, allowing traffic to pass over the Mississippi River just north of downtown for the first time in two years.

One lane in each direction will open at 2 p.m. Lane restrictions will remain in place until November. They will return in the spring to allow the completion of the $6 million project. All four lanes will be open to traffic from November until work resumes in 2013.

The repairs involve breaking out concrete around the corroded cables, replacing the cables and then pouring new concrete. The cables stretch the length of the bridge and hold together the box girders.

In south Minneapolis, the opening of the Lyndale Avenue Bridge marks the end of four years of upgrades along the busy street. The city, county and the Nicollet-East Harriet Business Association, businesses and residents collaborated to make a number of changes that began in 2008. They include:

Reducing the road from four lanes to two, adding turn lanes, adding center medians with trees and ornamental grasses, widening the sidewalks by three feet, and installing pedestrian friendly lights.

The segment of Lyndale from 38th Street to 50th Street was reconstructed in 2008 and the segment from 31st to 38th streets was redone in 2009. The completion of the bridge was the last part of the upgrades

"In 1997, residents from 10 neighborhoods along this corridor developed a vision for a 21st Century Lyndale Avenue that connected the neighborhoods, was safe for pedestrians and vehicles,and restored the grandeur of the avenue," said Hennepin County Commissioner Gail Dorfman. "Completion of this project is the realization of their dream."

A celebration called "Experience 54th and Lyndale" will take place from 11 a.m. to 4 p.m Saturday. Festivities will include a historic walking tour, treasure hunt, kids' activities and contests.