By Matthew Hersh

New speed limits along Nassau Street are now in effect as motorists contend with changes that, local officials say, were necessary to calm traffic on the increasingly busy throughway.

The Princeton Police Department announced last week that new limits had been set along two portions of the roadway, also known as Route 27, a state highway. Zone 1, which runs from Bayard Lane to Snowden Lane, now sets a 25-mph limit through the entire stretch. A second portion, Zone 2, further north along Princeton-Kingston Road, runs from Snowden Lane and Riverside Drive Extension and reduces the speed to 35, down from the previously posted 45 mph.

Princeton Police Chief Matthew Solovay said the public should begin to take note of message boards in the area alerting motorists of the changes. Solovay said there will also be an increased police presence to monitor, educate, and enforce the new speed regulations.

While local leaders continue to place Princeton’s Vision Zero initiative, which identifies and implements ways to reduce traffic-related fatalities and injuries while emphasizing access to transit and other modes of transportation, the speed reduction on Route 27 was primarily the result of resident advocacy.

The New Jersey Department of Transportation (DOT), which has final say over rules governing state highways like Route 27, approved the speed reduction in December, notifying Princeton that it has completed a comprehensive review and had considered factors including increased density of residential and commercial developments, the municipal zoning map, roadway configuration, road usage patterns by pedestrians, bicyclists, and transit users, and the historical context of the current speed limits.

Princeton Council advanced a formal resolution requesting the speed limit changes in November 2025 after working with DOT officials, residents, and municipal engineers, said Councilman David Cohen, chair of Princeton’s Code Review Council committee and who has worked to develop Princeton’s Vision Zero efforts.

Meetings with affected and concerned residents, including PTO meetings with parents at Riverside, resulted in constructive dialogue, Cohen said, including identifying where students use a “desire path” to cross 27 at Harriet Drive and Poe Road. It was then determined that a speed reduction would treat that residential area similar to others around town.

“We talk about safe routes to school, and for that quadrant of town it quickly came to the surface that a lot of the older kids who live around Riverside like to bike to the high school and the middle school,” said Cohen. “To find a safe way for them to cross 27 is key, and so we started talking about ways to make the places where students were already crossing safer.”

The reduced speed limits, Cohen said, coupled with the bike boulevards that exist throughout town, would create a safer environment in the immediate area, as well as encourage cycling. Bike boulevards are generally used to create a connected network of cycling-friendly roads throughout town that connect to various destinations. Sustainable Princeton highlights these mapped bike loops at sustainableprinceton.org.

Cohen said he and his Council colleagues were pleased with the response from the DOT, which can be a bureaucratic hurdle for many towns with state highways running through them. “I think part of what happened with the state is that they looked at our request and they agreed that there are enough houses along this stretch of 27 that it can be considered a suburban residential road. And so 35 is the speed limit to reflect that change,” he said.

Residents should continue to expect messages and notifications alerting motorists to the change, and police will be out educating speedy drivers to ensure that the new speed limits are known by anyone who normally traverses the King’s Highway.

“After that, we’ll see how the new speed limits are working and determine if a broader campaign is needed,” Cohen said. “If we need to do more, then we’ll certainly do more.”