Cambridge Community Speedwatch

This article was published in 2015, in Newsletter 120.

Police-facilitated Community Speedwatch operations across the county have helped save many villages from the blight of speeding. The urban environment presents its own challenges.


On a Sunday lunchtime at Parkside Police Station I sat with about a dozen other residents from many parts of the city to hear how Community Speedwatch works and how it will be introduced into the city. It is basically like ‘Neighbourhood Watch for cars’. Most had heard about the meeting from alerts on ‘eCops’ (an email and feedback service provided by the police giving local information on crime and antisocial behaviour) and attended because they had specific issues they were concerned about in addition to speeding, such as rat- running, traffic volumes and cyclists on footways. Speedwatch has previously been tried only in villages, and rather has the image of ‘a bunch of old geezers handing out tickets’. However, in effect it operates as a data-gathering exercise helping the police to target their resources more effectively towards extreme or repeat offenders.


Perceptions of the effects of speeding can be quite different from reality, so every Speedwatch operation has to have a proven need. At least a week before a Speedwatch exercise is conducted, a black-box data-gatherer is sited on a nearby lamppost or other street furniture at a height of three and a half metres. This unit contains a radar detector and can record the type (e.g. motorcycle, car, van, bus or lorry) and speed of all motor traffic passing that point. It does not contain any camera so cannot collect number plates. Data are collected for the week before the Speedwatch operation and for the week afterwards. The results are used to demonstrate the outcome of the activity, i.e. showing how much excess speeds have fallen. We were told that a typical data result from these black boxes might be, for example, 11,000 vehicles recorded in a week travelling in excess of 40mph in Bluntisham.


A Speedwatch operation comprises a group of three trained volunteers at a carefully selected location within the village. They have a big yellow sign clearly showing ‘Community Speedwatch’. There’s an electronic speed display board which is placed at the side of the road facing oncoming traffic. It has a radar detector that displays vehicle speed. The volunteers stand about 20 metres in front of the display board with clipboards, tally counters and voice recorders. Together they record the vehicle registration number, and optionally the type (car, van or motorcycle), colour and make of any passing motor vehicles that exceed the threshold speed. This is: (speed limit + 10% + 2mph).

After the exercise the data are transmitted back to the Speedwatch officer (known as SPOC – the single point of contact) who arranges for the data to be checked. Experience has been that communities are supportive of the Speedwatch volunteers and that it can be a sociable and friendly activity.


Letters are sent to the registered keepers informing them that their vehicles have been recorded as exceeding the speed limit. There’s no threat of fine or prosecution, but the letter is a warning of what may happen if the speeding continues. Weeks later the operation may be repeated and if the same number plates are recorded this can help the police decide whether to set up an enforcement activity. Repeat offenders have predictable patterns of speeding and so are easy to catch. Based on the information collected by the Speedwatch operations, the traffic cops choose a time and place where they are likely to catch many offenders. They use different devices to record speed for collecting evidence that would be accepted by a court. The Speedwatch officer said that many villages had been saved from the blight of speeding by these operations.


The current challenge is to try operating Speedwatch in an urban environment. The new equipment can be operated in 20mph areas, if a suitable location on the street can be identified. Letters will only be sent to offenders travelling at 25mph or more. I’m wary about taking part in this initiative myself as it may be seen as cyclists taking on motorists. So far I’ve only had a lukewarm response from followers of the relevant thread on Cyclescape, but if you are interested do get in touch.

Simon Nuttall