Positive effects of Edinburgh’s 20mph limits felt more than three years later

Evaluation of the effects of Edinburgh’s citywide network of 20mph limits more than three years after its roll-out reveals the measure may have positive impacts on active travel and air quality.

The measure continues to produce a drop in speeds, down from 23.77mph in 2016 before the roll-out, to 21.92mph in 2021 across the 65 streets surveyed.

This is a further reduction on 2019’s average speeds of 22.69mph, with an overall reduction of 1.85mph. The proportion of streets surveyed with average speeds of 20mph or less had also increased from 25% to 37% in 2021.

For every 1mph fall in speed research has shown a 5% reduction in accidents, while accidents that occur at lower speeds tend to result in less severe injuries, demonstrating the significance of these changes.

Additionally, road traffic collisions have continued to fall since the 20mph roll-out. Analysis of data from the 36 months following the introduction of the 20mph network showed a 30% decrease in collisions compared to the 36 months before, resulting in a 31% reduction in casualties.

The report demonstrates that since 2015, the percentage of residents cycling at least once a week in Edinburgh has gradually increased while participation in walking, wheeling and cycling on a regular basis (five or more days a week) has stayed consistent since 2019.

While the report also acknowledges a downward trend in harmful NO2 emissions across monitoring stations, national statistics show pollutants are reducing around the country. Due to this, and the fact 2020 may be an atypical year because of the impact of COVID-19, air quality trends should be considered with caution.

A consultation is proposed for later this year on the potential to further extend the 20mph network, which currently covers around 80% of the city.

Cllr Scott Arthur, Transport and Environment Convener said: ‘The citywide network of 20mph speed limits was introduced to help create safer, more liveable streets. When the scheme was first introduced it was hugely controversial, but now it has been confirmed as the right decision.

‘Research has shown that every 1mph fall in speed leads to a 5% reduction in accidents so it’s extremely encouraging that the latest evaluation of 20mph streets shows speeds are continuing to come down.

‘As Transport Convener I am committed to achieving Vision Zero, where traffic fatalities and severe injuries are eliminated, so that traffic collisions are also falling is reassuring too. Safer speeds, along with improved infrastructure, are essential to supporting safer, sustainable travel by foot, wheel and bike, as well as creating people-friendly streets.

‘I hope the Transport and Environment Committee will agree to my plan to consult residents on the biggest and boldest expansion to Edinburgh’s 20mph network since the scheme was introduced. We’ve taken a data driven approach to decide which streets to include, and now we will listen to residents. Our approach has one aim – saving lives.’

Photo by Roan Lavery