A 25-year construction project on the Manhattan Bridge ended Monday, with the lower level opening to Brooklyn and other commuters.

The lower level reopened complete with an HOV lane for buses and carpools of two or more people from 6 a.m. to 10 a.m. weekdays. The HOV lane is the first on an East River bridge.The government required the lane when it pledged funding for Mayor Michael Bloomberg's congestion pricing plan.

Two additional lanes were also added to the bridge, which is back open to bicyclists and pedestrians on separate paths.

Construction had been going on for 25 years to the tune of $829 million. Officials originally considered demolishing the then-structurally flawed bridge about 50 years after it opened in 1909.