The case in favour: No silver bullet but a life-saver all the same
More than 400 people were killed on London’s roads in 1990. Increasing volumes of traffic, unsafe roads and speeding prompted many to demand lower speeds in their streets and neighbourhoods. Over two decades, more than 300 traffic-calmed 20mph zones were introduced in residential areas.
In these new 20mph zones, the numbers of serious and fatal casualties fell by more than 40 per cent. But little changed on London’s main roads and town centres. This is where vehicles and people mix and the majority of serious and fatal casualties happen.
Now 20mph speed limits began to be introduced over large areas. These lower limits covered main roads where the risk to people walking and cycling was greatest as well as the residential streets. The London boroughs control 95 per cent of roads and in 2012 Islington was the first to move to a default 20mph speed limit on all its roads. Out of 33 London boroughs, 21 have either introduced a default 20mph limit or plan to.
After 2010, TfL started to focus on safe, attractive streets for people and began to look at the speed limits on its red route network. The 1,000 kms of network makes up five per cent of London’s road network and carries 30 per cent of its traffic but it is also where almost 30 per cent of serious and fatal casualties happen.
TfL introduced its first 20mph speed limit at the Imax roundabout at Waterloo in 2013. The programme grew slowly until the pandemic but has expanded rapidly recently towards the Mayor’s target of 140kms of 20mph limits on red routes by March 2024.
London still has more than 3,500 serious and fatal casualties every year and speed is a factor in over a third of these. Speeding traffic continues to blight communities and discourage people from walking and cycling. Those living in deprived areas are still more likely to be injured on the roads. The 20mph speed limits are not a silver bullet but they save lives.
Jeremy Leach is the London campaign co-ordinator at 20’s Plenty for Us
The case against: Blunt tool that will slow London down
In residential areas, near schools, and in some central locations popular with pedestrians, 20mph limits make sense and have a clear role in eliminating deaths and serious injuries. However, radically reducing speed limits on major arterial roads is wholly inappropriate.
We’ve seen the negative impact this has already had on Park Lane, the Westway, and many other roads, some of which changed from 40 to 20mph zones. These wide, multi- lane highways were designed to carry traffic, at volume, in and out of our great city. Vehicles now crawl along, with congestion building up more than ever before. This leaves traffic idling and undermines efforts to reduce harmful emissions.
TfL now plans to drastically reduce speed limits on more major thoroughfares in its road network, including sections of the A4 — a continuation of the M4 — a key route in and out of west London, and the A2 — a major access route for the south-east. The Transport for London Road Network covers just 5 per cent of London’s roads, but these strategically important roads carry 30 per cent of all traffic, keeping London moving.
London is a global city that people and goods in large volumes need to enter via road. That’s not to mention the many people who cannot complete their journey by walking, cycling or public transport, many of whom travel by taxi.
The mass rollout of 20mph zones is a blunt instrument. It makes little sense across a capital city in which 80 per cent of journeys are made via road and is resulting in congestion, confusion and chaos in many areas.
We are committed to making London’s roads safer and realising Vision Zero but believe more targeted approaches are required. At the very least, a proper debate about the use of lower speed limits is needed before Greater London becomes a 20mph zone by default.
