Restricted Roads (20 mph Speed Limit) Scotland Bill

January 17th, 2019 Posted by Blogs No Comment yet

The Scottish Parliament is currently considering making the default speed limit on restricted roads 20mph, rather than 30mph, as it currently stands. This arguably has the potential to reduce carbon emissions and air pollution, as well as increase road safety – but this is a controversial topic, and not everyone agrees. It is important that, regardless of whether you support or oppose the bill, you let Parliament know! You can respond to Parliament’s consultation survey here – it only takes a few minutes.

2050 Climate Group’s Policy Subgroup exists to help young people have their voice heard in decision making. We want you to do this based on your informed opinion. That’s why we have prepared this explainer to outline the purpose of the Bill, and the main arguments for and against it. Have a read, then fill out the survey so your views can be heard.

The deadline for survey submissions is 28 January 2019.

What is the Bill about?

The Bill would set the default speed limit on restricted roads to 20mph (instead of the current 30mph). Restricted roads are a type of road that is typically found in residential/urban areas. They are the roads around our homes and workplaces, where there are higher levels of pedestrians and other vulnerable road users.

Some local authorities, such as Edinburgh, Glasgow, Aberdeen, and Fife, have already introduced 20mph schemes. However, the limits of current legislation mean that these schemes had to be implemented on a road-by-road basis. This approach is complicated, time-consuming, and expensive for local authorities to administer, as they must specifically designate a change in the speed limit for road individually. By contrast, the Bill proposes making restricted roads 20mph by default – with councils retaining the power to implement 30mph limits on specific roads if they wanted (e.g., to create faster through-routes).

The Bill was introduced to the Scottish Parliament by Mark Ruskell MSP (Scottish Green Party) on 21st September 2018. It is currently being scrutinised by Parliament’s Rural Economy and Connectivity committee, who have issued a call for evidence on the issues the Bill covers. They want to know what people think about it – and that includes you!

What are the benefits of 20mph?

Evidence shows that roads that are 20mph are safer for everyone – drivers, pedestrians, cyclists. 20mph roads have lower rates of serious and fatal traffic incidents, as drivers have more time to react to their surroundings.

Reducing speed of traffic also encourages more people to use active travel (walking and cycling). A perception of cycling as being ‘unsafe’ because of passing car traffic is a major barrier for many people. Reducing the speed limit will make cycling a more attractive mode of transport, and make pavements more pleasant places to walk. This in turn could lead to huge public health benefits, as regular exercise is key to maintaining a healthy lifestyle with fewer health difficulties.

20mph could also be better for the environment. Firstly, if more people walk or cycle rather than drive, then overall emissions will be reduced. Reducing car journeys is vital for Scotland to reach its emissions targets, given that transport is the largest source of greenhouse gas emissions.

Secondly, on an individual level, most fossil-fuel-powered cars produce fewer emissions when travelling at 20mph as opposed to 30mph. Diesel and petrol cars both produce a mixture (in different quantities) of nitrogen oxides (NOx), carbon dioxide (CO2), and particulates (PM) when running. When travelling at 20mph (as opposed to 30mph), both petrol and diesel cars produce much fewer particulates – a major cause of poor air quality that is extremely damaging to people’s health.

Additionally, the reduced speed means that drivers need to brake, accelerate, or change gears less, and can maintain a more constant speed. This reduces wear-and-tear to vehicles – especially to brakes and tyres, which are another source of PM air pollution. Maintaining a constant speed is also a more fuel-efficient way of driving.

When travelling at 20mph, diesel cars produce significantly less NOx, and slightly less CO2. Petrol cars actually increase their emissions of NOx and CO2 when travelling at 20mph – but some studies suggest that the difference in the numbers of petrol vs diesel cars, and the substantial drop in emissions from diesel cars, more than makes up for this increase from petrol cars.

Whilst the science isn’t settled on the issue of how 20mph affects greenhouse gas emissions from vehicles, it is clear that air pollution from PM would improve. Furthermore, proponents of the Bill would also argue that the road safety aspect is more important, and also that by reducing the speed of car journeys we can discourage their use, and in the long run reduce the total number of cars on the road.

Finally, the Bill would introduce 20mph speed limits through new signage and a public awareness campaign for motorists. By relying on signage, the implementation costs for local authorities would be significantly less than if new street design measures, such as speed bumps, were added to residential streets across the country. This approach would also reduce the administrative and financial complexity for local authorities. Adopting a blanket 20mph approach is cheaper and simpler in the long-run.

What are the arguments against the Bill?

Existing 20mph schemes tend to be based around areas with lots of vulnerable road users – e.g. schools, hospitals, and care homes. By increasing the number of 20mph streets, the ‘specialness’ of current schemes is reduced. This might lead to drivers taking less care around places like these that need extra protections.

Furthermore, a speed limit is less effective without proper enforcement. Drivers regularly break and ignore speed limits without any repercussions – so reducing the speed limit further will frustrate drivers even more, and possibly lead to more dangerous driving. For the Bill to be properly effective, it must be accompanied by sufficient traffic policing resources.

It can also be argued that there are other, more effective ways to improve road safety.

Firstly, the law could be updated to properly recognise motor vehicles as potentially lethal weapons, and increase punishments for dangerous driving offences. We could also introduce presumed liability for drivers in cases of collisions with pedestrians and cyclists. Under this system, the presumption of guilt would lie with the least vulnerable road user – so a motorist would have to prove they were not responsible for a collision with a pedestrian cyclist. This is a common approach in many European countries – the UK is one of only 5 that has not adopted some form of presumed liability.

Secondly, for a 20mph scheme to be really effective, roads must be (re)designed to encourage slower speeds – changing signs from 30 to 20 isn’t sufficient. A better way of improving road safety would be to narrow roads, and build speed bumps and chicanes, as these features physically force motorists to reduce speed. (However, doing this on a national scale would be prohibitively expensive).


Now please take a few minutes to fill out Parliament’s survey and let them know your views on this important Bill:


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