Small reductions in speed greatly increase survival rates

Evidence from many studies confirms that a 20mph speed limit does reduce average speeds.
An extensive before-and-after study by Napier University of vehicle speeds in villages found that 85% of drivers dropped their speed by 3 mph. That may not sound much, but even small reductions in average speed greatly improve survival rates for pedestrians and vehicle occupants (see “The effect of speed panel”).

 

 Vulnerable road users in Burwell
When it comes to road safety, most people are aware that children are a vulnerable group, but as the panel above shows, the over 60s are also at risk:

 

• 20% of Burwell residents are aged 0-17
• 29% of Burwell residents are over 60

With almost half the population of Burwell being in one of the vulnerable age groups, it becomes even more important to reduce vehicle speeds. That remains true, even if full compliance with the actual speed limit is not achieved.

 

Partial compliance still saves lives
 In a 2022 study by NIHR, prior to the introduction of 20mph restrictions, 45% of cars in Edinburgh travelled faster than 25 mph – one year later, this had dropped to 31%. We know that compliance with both 20mph and 30mph speed limits is far from perfect, but what matters is that average vehicle speeds in 20mph zones are significantly lower than in 30mph zones. (See also: Does a 20mph speed limit really improve road safety?)

Sources

Napier research
The effect of speed 
NIHR study