Mercer County is in the planning stages of replacing the Washington Road bridge over Lake Carnegie, which is over 120 years old.
The bridge has been deemed “structurally deficient,” Deputy Director of Mercer County Communications Sam Weiss wrote in an email to The Daily Princetonian, although he said that “residents should not have any concerns about using [the bridge] day-to-day.”
Portions of the Washington Road bridge have undergone maintenance and refurbishments over the past couple of years. The section of the bridge over the Delaware and Raritan canal was closed for several months over the summer of 2023 for “emergency” repair. The same section received additional repairs in Oct. 2024.
However, the proposed changes would be the first significant work on the Lake Carnegie portion in the past several years.
Future construction may also see the intersection of Washington and Faculty Road being turned into a roundabout, Weiss said.
“The design and construction of the roundabout are being conducted by Princeton University, with support and oversight from Mercer County,” he added.
He estimated that conversations about the roundabout have been ongoing for about five years, and that it would be some time before any construction moved forward.
“No final determinations have been made at this time regarding the configuration of lanes, but the new bridge will have the same overall width as the existing structure,” said Weiss.
“Mercer County values the historic nature of the Washington Road bridge,” he said. “We are committed to working with the NJ State Historic Preservation Office to bring the bridge in-line with modern safety and engineering standards while maintaining its aesthetic value.”
The municipality will have at least one public meeting with the community while designing the bridge. The next public meeting has yet to be scheduled and could be more than a year away, according to Weiss.
“The design and permitting process will play out over the next several years and will involve multiple public meetings to share information with, and solicit feedback from, the local community,” he said.
The Washington Road bridge is a key commuter artery for professors as well as graduate students living in the Meadows apartments.

David Yun is a staff News writer for the ‘Prince.’ He is from Rochester, Mich. and can be reached at dy3599[at]princeton.edu.
Please send any corrections to corrections[at]dailyprincetonian.com.