London has one of the most advanced traffic surveillance system in the world. London traffic control centre(LTCC) servile spooling network of roads. London is circled by Britons most expensive roads, worlds biggest ring roads, 6 lane M25. Every rush hour M25 feeds equivalent of 25 free way lanes into the city.
More traffic into the same constrained space result in grid lock. LTCC's job is to avoid grid locks.
On 80 screens it get the real time view of streets of London. Other cities monitor traffic jam after they form. But London can predict and even head them off. It is all done with central office management of integrated traffic(COMIT) system.
Embedded in London streets are 3000 electronic sensors. Sensor detects when a vehicle passes over and measures time travel to next sensor. Average time of travel between adjacent sensor is stored 100 times a minute. When traffic speed falls to lower average the system alerts and feeds to COMIT map in control centre. Green means no congestion, light blue means congestion has increased by 10%, dark blue up to 50%, red more than 50% congestion(grid lock). The LTCC team then can manipulate computer operated traffic signals and reduce the congestion.
Most of the time there is no need for LTCC team to do anything. The traffic lights are so smart that they constantly monitor the traffic at their intersection and reset the timing for ideal flow.
To keep traffic rolling this city relies on more than sensors and traffic lights with minds of their own. At very heart of the city the volume of traffic exceeds capacity of streets. The solution is not improving flow but subtracting cars. Today motorists in central London are travelling in another dimension. The dimension not of space or time but of cash. There is a sign board - next stop congestion zone. Don't even think of entering the congestion zone if you haven't paid. That’s the solution to reduce crowd by hitting motorists where it hurts, in the wallet. 5 pounds per day to enter congestion zone.
But with the quarter million vehicle entering a day how do you keep track of who has paid and who is cheating? The zone is servile at 174 entry points. two cameras at each point. Whenever a vehicle passes one camera records the licence plate and other background. With vehicles moving in and out of the congestion zone cameras takes million pictures a day. With the picture finding freeloaders is done at secret place in east London. In real time the system reads the plate as numbers and letters and sort out legal drivers from cheaters. The technology is so good that you can take it to the court. The fine for not paying congestion charge is 100 pounds.