Traffic Light Detectors. Benjamin Rondel // Getty Images. ... system uses a series of underground wires charged with alternating current to detect a vehicle once it rolls over the circuit.

The center can actively signal timing, but city staff can view traffic through closed-circuit television and also change the lights manually if it is required, the city states.

GRAND RAPIDS, Mich. (WOOD) — The city of Grand Rapids and Consumers Energy are investigating what may have caused a power outage that darkened traffic lights early Monday morning. The outage was ...

GRAND RAPIDS, Mich. — Digging can be seen at Monroe and Coldbrook in the city's northeast side in front of the decommissioned water pumping station, where the city's primary circuit that serves ...