Albuquerque and Portland test lights that reward drivers at the limit

On Lead Avenue in Albuquerque, the sound of cars racing through the night has begun to fade. Isaac Romero, who lives along the corridor, remembers crashes that flipped vehicles and one impact that shook his house. Now, the city says its speed-sensing traffic lights are helping cut crashes and injuries by giving drivers who respect the limit an earlier green—and making speeders stop more often.

The system is a targeted version of “rest in red”: signals default to red until a vehicle approaches. Albuquerque and Portland add speed sensors, so a driver traveling at or below the posted limit can receive a much earlier green light. Jennifer Turner, Albuquerque's director of municipal development, said drivers learn quickly that speeding along Lead and Coal avenues means stopping. The city has also installed three speed cameras near the corridor.

Portland recently began testing the approach during late-night hours on Southeast Powell Boulevard, a busy state highway with a history of crashes, including fatal ones. At the first intersection, Peter Koonce, who manages the city's signals and street lighting, reported that the average speed fell from 39 mph (63 kph) to 30 mph (48 kph)—the speed limit. Oregon State University researchers helped select the detection system and are now evaluating how it performs.

The evidence is encouraging but incomplete. David Hurwitz, the transportation engineering professor leading Portland's study, said the approach “seems like it has potential” while stressing that more research is needed. Jay Beeber of the National Motorists Association argues that some drivers may simply become frustrated without understanding why a light stays red. A 2023 study cited by the North Carolina Department of Transportation found a 43% reduction in total crashes on five rural and urban roads after a different, sensor-free version of rest in red was introduced around the clock.

So what changes in practice? For residents along dangerous corridors, the immediate goal is fewer high-speed passes and crashes without relying only on punishment. For drivers, keeping to the limit may mean fewer stops. For cities, the approach offers a way to use existing traffic signals to influence speed, but Portland's test still has to establish whether the benefit survives outside the first intersection and without creating new red-light violations.