Why more cyclists are being seriously injured and killed in Edinburgh

7 min readMar 7, 2024

For most road users, Edinburgh is safer than ever before. Yet the number of cyclists suffering serious injuries or being killed is increasing. Why?

The good news

Over the last 20 years, there has been a remarkable 69% fall in road casualties in Edinburgh. The implementation of 20mph speed limits was highly effective, with car occupants in particular now much less likely to be hurt.

Broken bones

However, this overall fall in casualties was driven by a reduction in those suffering slight injuries such as whiplash or sprains. Serious injuries, like bone fractures, deep cuts and concussions, have persisted throughout the period, apparently unaffected by the introduction of 20mph limits.

KSI = Killed or seriously injured

Paradoxically, this means the average severity of injuries has increased!

Who is being seriously injured?

Breaking the data down by type of casualty, we find that KSIs have fallen by 8% for bus passengers, 29% for car occupants, and 48% for pedestrians from 2002 to 2022. However, there has been a 91% increase in cyclist KSIs, explaining why the overall figure is so resistant to change.

Excluding cyclists sees overall KSIs fall more in line with slight injuries, though there is a lot of chop in the data.

Overall casualties and motor vehicle traffic

The total number of overall road casualties is now much smaller than what we would expect if road traffic volume is the primary driver of road collision casualties.

In particular, a 41% increase in traffic from larger vehicles such as vans, HGVs and buses over the last 20 years appears to have had no effect at all on the number of KSIs. Indeed, slight injuries have fallen even while vehicle mileage has increased.

Cyclist KSIs during COVID-19

COVID-19 restrictions in 2020 led to a 26% reduction in car mileage and 10% fall in larger vehicle mileage such as lorries, buses and vans. The number of pedestrians in the city centre also fell as tourism dried up and people started to work from home.

This fall in traffic coincided with a 29% reduction in KSIs, including a 63% fall for car occupants and a 51% fall for pedestrians. Slight injuries fell by 46%, with fewer bus passengers and car occupants in particular being hurt.

However, there was a 20% increase in cyclist KSIs compared with 2019 (50% compared with 2015), though slight injuries continued to fall.

Like many others, I started cycling in Edinburgh for the first time during lockdown, taking advantage of the quieter roads and stunning weather. In contrast to other forms of transport, there was a 14% increase in bicycle traffic in Edinburgh in 2020, even while cycle commuting fell significantly.

That’s why cyclists bucked the trend.

Why cyclist KSIs will continue to increase in Edinburgh

It would appear that the primary reason why cyclist KSIs are increasing is that… the number of people cycling is increasing.

Not my finest analytical moment?

But vehicle and pedestrian traffic has increased too, even while those types of casualties have decreased. Interventions like 20mph limits did not reduce the number of cyclist casualties in the same way they did slight injuries to car occupants, for example.

And then a reduction in road traffic during COVID-19 coincided with an increase in cyclist KSIs. What is going on?

Perhaps Edinburgh’s congestion problem slows traffic down so much that increased vehicle traffic has actually contributed to the fall in other types of road collisions. On the other hand, vehicle traffic puts people off cycling, with cyclists highly responsive to the quieter streets during COVID-19.

Perhaps Edinburgh’s Future Streets plan, which will see restrictions on some vehicles in the city centre, will encourage more people to take up cycling even while increasing average motor vehicle speeds.

Cyclist KSIs may continue to increase. Other types of KSI might start to increase too.

How to make cycling safer in Edinburgh

From what we can glean from collision data, there are three ways in which we could slow or reverse the increase in cyclist KSIs:

Enforce 20mph limits in the city centre if congestion dissipates.
Invest in coherent cycle infrastructure. While more cycle lanes (e.g. Leith Walk) and quieter streets encourage cycling, the effect on safety is offset if these new cyclists still need to negotiate busy streets with no protection to cross the city (e.g. Leith Street).
Focus efforts on junctions, particularly crossroads and roundabouts, which tend to be more dangerous for cyclists than other road users.

KSIs might stop increasing for another reason. As traffic continues to increase, and as the number of cyclist KSIs receives more attention in the press, more people will be put off cycling and therefore the number of KSI will reach a new equilibrium.

Cycling mileage in Edinburgh has fallen by 20% compared with 2020 levels, but the segregated cycle lanes on Leith Walk are 76% busier than last year.

Some more detail

What vehicles are involved in cyclist KSIs?

Over the last 20 years, cars have been involved in collisions where 510 cyclists have been killed or seriously injured. Vans have been involved in a further 65.

This data does not indicate who was at fault, just which vehicles were present at the collision.

Only 29 KSI collisions involved a bus, and 12 involved a HGV (often fatalities, as we have been so sadly reminded recently). 20 cyclist KSIs involved another cyclist, and 62 serious cycle casualties involved no other vehicle. These vehicle-less collisions were clustered around the tram tracks at Haymarket and Princes Street…

The types of vehicle involved in cyclists KSIs does not vary much year-to-year.

Where are cyclists being seriously hurt?

While pedestrian and bus passenger KSIs are closely concentrated on the city centre, cyclist KSIs are more evenly spread out. That’s why interventions may need to be across a wider area than just the city centre.

A quick note on interpreting the above figure.
Think of Lothian as a flat, calm sea. Edinburgh pokes above the waves, with the highest point represented by the deepest red colour. There is a smaller island out at Hermiston, sometimes connected by a long isthmus.
The height of these “islands” depends on the relative concentration of road collisions in that area compared with Edinburgh as a whole. Each island’s height is scaled to the total number of casualties by each type— that’s why the “Isle of Bus Passenger” appears to be as high as the “Isle of Pedestrian”, even though there are fewer casualties.
There are still sporadic collisions happening out at sea.

Junctions

Junctions are key for cyclists. 72% of cyclist KSIs occur at them, compared with 53% for pedestrians and 44% for car occupants. The introduction of 20mph limits had a dramatic impact on the number of casualties at T-junctions, for example.

Happily, dangerous junctions are easy to identify in the data. The crossroad at Easter Road and Dalmeny Street is an obvious example, as is Crewe Toll Roundabout. The notorious Portobello junction is another, while KSIs “not at a junction” cluster on Princes Street’s tram tracks.

Since the introduction of 20mph limits, casualties at T-junctions have fallen more quickly than those at roundabouts and crossroads, suggesting that vehicle speed is more of a factor at the former.

20mph changes the shape of the city

The distribution of casualties across the city changed after the introduction of 20mph. While the city centre remains the hottest spot for casualties, casualties are now evenly spread across the city.

This would suggest that there was a relatively large impact on areas like Leith and the Southside, where there is plenty of motor vehicle traffic travelling at relatively higher speeds. Meanwhile, slower average speeds in the congested centre reduced the impact of the introduction of 20mph limits in that area.

Relatively is an important descriptor here. Casualties fell across the city, including in the city centre.

As the number of KSIs has remained broadly flat, the changed relative distribution of these types of injuries represents an absolute change. That means that 20mph had less impact on serious injuries in the city centre, but elsewhere they are now more evenly spread.

Casualties by age

Children are distinctive for sustaining relatively more injuries outside of the city centre, with hotspots across the city.

A closer look finds that most child pedestrian and cyclist casualties are centred on particular locations. While Edinburgh-wide road safety measures will help to an extent, policies that target specific streets or areas across the city will have the most benefit for younger people.