The University of West England has conducted an elaborate study of the effects of lower urban speed limits in Bristol. The study looked at individual speed data from more than 36 million vehicle observations and controlled for other factors that might affect changes in traffic speeds, representing a more sophisticated analysis than previous studies of 30kph limits. Bristol Health Partners reports:
The 30kph speed limits in residential areas in Bristol have prevented more than four fatal casualties a year, as well as 11 serious and 159 slight injuries. This is estimated to have saved the NHS £15 million a year
The research also showed average speeds have dropped by 4.3kph in the areas with 30kph limits – a larger reduction than other cities have seen. Speeds reduced in 100 of the 106 roads that the researchers looked at. Critics of 30kph limits often cite a lack of compliance as an argument against the schemes. However, this evidence suggests that, overall, while drivers may not be driving below 30kph, they have reduced their speeds by a significant amount.
Dr Suzanne Audrey, Senior Research Fellow in Public Health at the University of Bristol and co-Director of the Supporting Healthy Inclusive Neighbourhood Environments Health Integration Team (SHINE), welcomed the findings, saying:
“This is vital evidence that 30kph limits are effective – both in preventing casualties and encouraging healthy behaviour in the neighbourhoods where they’re brought in. If more people feel they can walk and cycle around residential areas rather than get in their cars, this brings enormous benefits to health, community cohesion and air quality.
The introduction of lower urban speed limits is overwhelmingly popular:
The latest YouGov 2017 survey revealed 62 per cent of Bristolians support the limits on residential roads, and 72 per cent support them on busy streets. These levels are very similar to the rest of the UK.