There is no evidence that signed-only 20mph speed limits, which have been trialled across Hampshire since 2012, have improved road safety.
That is the headline conclusion following monitoring of the effects of the 20mph limits on vehicle speeds and casualties at 14 pilot schemes in residential areas.
The report was presented to Hampshire County Council on 5 June by Martin Wiltshire, the county’s highway safety manager.
The report says that while four of the pilot schemes have ‘demonstrated compliance’ with the 20 mph speed limits, ‘these have merely served to formalise existing low speed environments with very marginal speed reductions having been achieved’.
Reductions elsewhere are described as ‘modest’ and in some cases average speeds ‘have even increased’.
The only pilot schemes where average speeds are ‘below the new speed limit’ are in areas where averages were already under 20mph.
In terms of collision and injury data, the impact of the pilot schemes upon road safety is ‘projected to be neutral’, and the report says there is ‘no evidence of enhanced road safety benefits compared with that observed for the entire road network maintained by the county council’.
Hampshire Constabulary are not ‘routinely enforcing’ the 20 mph speed limits, except in circumstances where there is ‘evidence to support that a road or a given location presents a heightened risk’, which, the report says, ‘would in any case be consistent with the county council’s traffic management policy since 2016, which requires the prioritising of safety and casualty reduction initiatives over all other interventions’.
The report says the pilot schemes received some positive feedback from residents, the majority of whom observed that their own driving behaviour has become ‘more compliant’ as a result of the pilots – and one third had noticed a decrease in speeds in their area.
However, the majority of residents felt that motorists continue to exceed the speed limit and the report concludes that the pilots do not appear to have ‘won round’ residents who were initially opposed to the introduction of the 20mph limits.
Residents who responded to the survey felt that better enforcement and a more targeted approach to applying 20 mph speed limits would improve their effectiveness.