Rockburner wrote: Sun Apr 26, 2026 9:35 am
Slight derail, but apparently the 20 limit is being considered a massive success in road safety circles, so don't think it's going to go away anytime soon.
The numbers they're getting for incidents and injuries show a huge reduction in 20mph areas.
That'll be the Welsh data, with England as the experimental 'control' set.
However, given the reluctance to introduce Graduated Driving Licenses, despite substantial evidence, a nationwide 20 limit may still not happen.
Edit: Google says:
The implementation of a default 20 mph speed limit on restricted roads in Wales (introduced on 17 September 2023) has resulted in a significant reduction in road casualties, with data for the first full year showing roughly 100 fewer people killed or seriously injured.
Key Data Reduction Findings (First Year: Oct 2023 - Sept 2024)
Total Casualties: Road casualties on 20mph and 30mph roads combined fell by 28% compared to the same period the previous year.
Collisions: Recorded collisions on 20mph/30mph roads dropped by 26%.
Fatalities/Serious Injuries: The number of people killed or seriously injured on these roads saw a reduction of around 100 in the first year.
Speed Reduction: Average speeds fell by approximately 4mph on main roads.
Insurance Claims: Insurance company esure reported a 20% decrease in vehicle damage claims within these areas.
Contextual Factors
Performance: The first full year data indicates the policy has resulted in the lowest number of casualties in the third quarter of 2024 since records began.
Regional Variation: North Wales saw a 46% reduction in casualties, with 94% of roads changing from 30mph to 20mph.
Compliance: Data from GoSafe indicates that 97% of vehicles monitored since January 2024 were traveling below the enforcement threshold of 26mph.
Long-Term Trend: While casualties have been on a downward trend for the past decade, this reduction was described as the most successful road safety intervention in modern times, yielding a reduction nearly three times larger than the previous highest year-on-year drop.
Reversals: Following public feedback, some local councils have begun reversing the 20mph limit back to 30mph on specific roads.
Economic and Social Impact
Implementation Cost: The cost to implement the 20mph limit was approximately £34m.
Prevention Savings: Public health researchers estimate the casualty reductions could provide around £92m in annual prevention savings.
Economic Disbenefit: A Welsh government assessment projected an upper-bound "disbenefit" of £9 billion to the economy over 30 years due to increased journey times, although this figure is debated.