What is a green wave?

• A. Coordinated green signals along a corridor enabling continuous movement at a set speed.
• B. A single long green signal.
• C. A signal that never turns red.
• D. A pedestrian-only signal.

Answer: (A)

A green wave focuses on coordinating signals so a vehicle can travel along a corridor and encounter green lights at successive intersections without stopping, by timing the greens to match a specific travel speed. Engineers set cycle lengths and offsets so that, if you drive at the designed speed, you reach each intersection just as its light turns green. This creates smooth, continuous movement, improves travel time reliability, and reduces stops and fuel use. It isn’t just one long green at a single intersection, and it isn’t a signal that never turns red or a pedestrian-only signal—these don’t achieve coordinated progression along multiple intersections.