Worcester speeding contour maps
People using a bike as a mode of transport often have a heightened awareness of the risks around using our roads. The reasons for this are fairly obvious; the exposed nature of cycling compared with driving in that you are not encased in a metal box resulting in better visibility and hearing, with a more elevated position also improving lines of sight. In addition the vast majority of cyclists will also be users of motor vehicles, as well as making journeys by foot. Why is this relevant? Well, it means they will be making observations of other road users' behaviour at a range of speeds about 3 mph (walking), 12 mph (cycling) and anything the range a car offers; lets go with the legal limits of 0 - 70 mph.
Regardless of whether you cycle regularly or not, it is likely that you have witnessed people driving over the speed limit, or at an inappropriate speed for the road / conditions. The problem with speeding, not least it's illegality, is that it increases the risk of a road traffic collision (RTC), both the likelihood and the severity. RTCs are bad (hopefully we can all agree on that) causing damage to private and publicly owned stuff (other cars, or road infrastructure) which has to be repaired. More RTCs result in more injuries, and more injuries at some point result in fatalities. Each RTC also normally requires police attendance, and may end up as a case in the court system, all a drain on societies resources.
Of course, it's easier for everyone to turn a blind eye to the problem, rather than to acknowledge and tackle the issue. In my experience, whether dealing with parish, city or county councillors, council officers or the police, there seems to be a reluctance to tackle speeding, sometimes suggesting there's nothing that can be done, or it's someone else's problem. A common cited reason is that it's not really an issue, despite anecdotal observations by the public, or perceptions: 'Calm down dear, you don't know what you're talking about, we've got lots of data to prove it's not an issue'.
Let's look at the data
Worcestershire County Council have pretty good data sets for traffic surveys undertaken at different locations in the city, which include vehicle counts and speed measurement. This was kindly provided via the Freedom of Information process, and has been reviewed by Bike Worcester, the results of which can be viewed on the traffic survey map here. In each case we have determined the following parameters which can be seen on the graphs revealed by clicking on each location. Where the traffic survey was undertaken over several days, the mean of the data was taken.
Total number of vehicles each hour
Total number of vehicles speeding each hour
Percentage vehicles speeding each hour
Maximum recorded speed each hour
In summary, in some locations there is almost 100% compliance with the speed limit, in other locations the perception that speeding is a problem is backed up by the data, in both severity (max speeds), frequency (count of vehicles speeding), and proportion (% age of vehicles speeding). This can be seen to vary dependent on the day of the week and time of the day. Making reference only to the average speed is unhelpful, and ignores the smaller percentage of drivers who drive far in excess of the speed limit. In addition periods where roads are full of stationary traffic drag down this average, so it is unlikely to be reflective of 'normal' driving conditions. It's complicated.
If we add up all the incidents of speeding, and extrapolate this over a period of a year, then the count of incidences runs into the millions. Just in Worcester. Measured at a limited number of locations.
Worcester, we have a problem…
To make the data more visual and accessible we then created the heat map shown below, which displays all of the 2022 data. The map can be changed with the drop down in the bottom let hand corner to show the following statistics:
Mean speed
Difference between the mean speed and the Speed Limit
85 percentile speed
Difference between the 85 percentile speed and the
Speed Limit
Count of vehicles breaking the speed limit
% of vehicles breaking the speed limit
Max recorded speed
Count of all vehicles
We think this is a useful tool to reflect on the data, and to highlight problem areas. There is more data available, notably from the Vehicle Activated Speed Signs installed around the city. We are hopeful this data is also made available, and can be added to the information displayed here.
So, in conclusion. If you think there is a problem with speeding on a particular street in Worcester, there probably is. We don't have to accept this. Contact your city and county councillors, and demand action. Streets can be subtly redesigned, slowing drivers, or traffic can be diverted using modal filters to direct traffic where we want it to go. Lets collectively call out speeding for what it is; illegal and antisocial behaviour that increases the risk of RTCs, leading to destruction, injury and death.
