By Anne Levin

The bridge over the D&R Canal on Alexander Road is scheduled to be closed starting sometime this summer while the New Jersey Department of Transportation (NJDOT) replaces the span. At the same time, Mercer County will be replacing a nearby culvert and the bridge over the Stony Brook. The closure is expected to last through spring 2020.

Traffic tie-ups are inevitable. “It’s going to cause traffic issues, obviously, and we’re going to be discussing in more detail what the detours are going to be,” Mayor Liz Lempert said during the December 17 meeting of Princeton Council. “The good news is that both bridges are going to be worked on at the same time, so we won’t have to shut it down again to work on each one.”

On December 19, the NJDOT held a public information session at Monument Hall. Traffic was chief among the concerns of the approximately 50 people who attended. During the replacement projects, Alexander Road will be closed between Faculty Road and Canal Pointe Boulevard. The primary detour route being recommended is Faculty Road and Washington Road.

According to the NJDOT, the D&R Canal bridge, which was built in 1948, is in poor condition. It has one travel lane in each direction and no shoulders. Since it is located within the Delaware and Raritan Canal Historic District, along with the associated Camden and Amboy Railroad Branch Line and Princeton Basin historic districts, the project required a public forum to obtain public comment on issues related to the protection of historic resources under the New Jersey Register of Historic Places Act.

Replacing the old bridge will be a single-span bridge made of a concrete deck, supported by galvanized steel beams founded on reinforced concrete abutments. Both lanes will be 2 feet wider, with a 5-foot shoulder on each side. Each side will have timber sidewalks with concrete curbs. The outer edge will have a wood facade.

While the roadway is under municipal jurisdiction, the D&R bridge is owned by the state, and the span over the Stony Brook is owned by the county. Construction of the bridges will be coordinated between the state and the county.

At the December 17 Council meeting, Lempert looked for a silver lining. “This is planned for as opposed to having an emergency repair that’s necessary,” she said. “We have a long time to get ready.”