Many traffic signals were originally installed due to high accident rates and poor vehicular flows at junctions. Switching off signals would result in numerous incidents and regular gridlock for vehicles as well as making it more difficult and unsafe for pedestrians and cyclists to cross.
While smart traffic signals (ones with sensors to detect different types of vehicles and use that data to alter traffic flow) may help to keep traffic moving and have been trialled in Cambridge, they will only alleviate congestion slightly in certain locations. Congestion can only be brought down to reasonable levels by providing viable alternatives to driving and thus decreasing the number of journeys taken by motor vehicle.
The GCP estimates that its proposals for a Sustainable Travel Zone would halve congestion in Cambridge. If this were to happen, many junctions (such as Mitcham’s Corner and those on Newmarket Road) could be reimagined to improve journey times and the public realm.
You can read more about smart traffic signals here.