Work Begins On US 1 Bridge Over Mamaroneck River

MAMARONECK, NY — Congestion is likely on Boston Post Road for the next three weeks as crews work on a bridge over the Mamaroneck River near Harbor Island Park.

A major construction project starts on June 7. Crews will begin test pitting work ahead of plans to reinforce the stone arch bridge on the heavily traded thoroughfare. Initial work will take place between 9a.m. and 3:30 p.m. for most of June.

At least one lane of traffic in each direction is expected to remain open during the bridge work. The New York State Department of Transportation (NYDOT) hopes to keep two lanes of traffic moving in each direction, but lane closures are possible during off-peak times.

"The existing natural stone arch structure is over 100 years old, needs repairs and is missing mortar between the stones," the NYDOT said in a factsheet announcing the infrastructure project.

"Full replacement is needed because of hydraulic vulnerability and potential scour, which could undermine the bridge. The Bridge will be widened and pedestrian walkway will be installed."

The U.S. Route 1 stone arch bridge over the Mamaroneck River will be reinforced and strengthened with a steel liner installed underneath the bridge. The physical structure supporting part of the Harbor Island Park pocket park at the southeast corner of U.S. Route 1 and Mamaroneck Avenue will be removed entirely and replaced. The pocket park will be reconstructed and a new sidewalk will also be installed on the south side of the new bridge.

The bridge replacement project is part of a capital improvement initiative in Westchester County. The initiative known as the "Lower Westchester Bridge Bundle" also includes the replacement of the East Lincoln Avenue bridge in Mount Vernon and the Saw Mill River Parkway bridges.