20’s the limit – how to encourage speed reductions

Organisation: Wales Centre for Public Policy 
Date uploaded: 21.10.20
Date of publication: 07.20

This report says a comprehensive programme of behaviour change interventions will be needed to change drivers’ habits and build a 20mph culture across Wales.

Plans to make 20mph the default limit for residential areas received backing from the Welsh Government in July 2020 – following the culmination of a year-long study.

This report describes the introduction as a bold and exciting step that will, if complied with, improve quality of life for people living in the country.

It calls for an integrated package of measures, including a balanced mix of enforcement, engineering and promotion interventions in order to maximise impact across all geographies and demographics. 

The report reads: “A behavioural change programme to support the Wales 20mph default should be tailored according to data on driver groups, locations and stakeholder commitment. 

“Targeting ‘average’ drivers to reach a tipping point in mainstream compliance would likely be a cost-effective approach. This would include mobile vehicle activated signs, positive messaging, pop-up police enforcement, speed awareness courses and localised reengineering of junctions/roads.”

The report also says that future technology offers the potential to increase compliance – with the introduction of Intelligent Speed Adaptation (ISA) on all new cars by 2022. However, it adds that benefits will not be automatic, as drivers will be able to override the system.

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