There’s been discussion about traffic flow in #Edinburgh. So we looked at the data on a city-wide basis. Its true: traffic flows less than in 2000! But read on… all is not what it seems
Traffic flow compared to 2000 has dropped. Significantly - by 16.7%. But that’s if you include the 2020 and 2021 data which was affected by COVID! Those years were pretty unique!
But if you exclude COVID years, traffic flowing past monitoring points is… increasing!
We also removed data points that didn’t have data for all years. So we have 22 years of like-for-like data 2000-2021. This is all based on the average day’s traffic passing monitoring points.
Bus lanes increased by c35%+ between 2000 and 2008 - when net traffic flow across the city also increased. So prioritising buses whilst restricting space for other vehicles may not impact flow on a city wide basis
That’s good as bus lane extensions are coming soon!
But what happened in 2010-2014?
recession?
phase 1 tram work?
Macro effects likely at play. Unless there was a delayed effect of the bus lanes (unlikely!)!
Between 2000 and 2020. Many monitoring points observed flow decreases, but most increased.
The city-wide trend is clear - Up up up!
In 2019, 80,000 more vehicles flowed past the same monitoring points per day than in 2000. c1.8m passes per day increased to c1.9m passes per day.
There’s no measure of capacity though. For routes where there weren’t trams or bus lanes in 2000, it’s conceivable (likely!) the overall usage is much higher. Basically you have more folk on a bus or tram than in a car with 1.2 person average occupancy
So there’s more traffic flowing and the data (see blog number 5) also shows overall miles driven overall is up. By an even bigger proportion.
We also know there are 19,800 more registered private cars in Edinburgh since 2009 - a 14% increase. Likely this could be close to 20% if backdated to 2000. 20% more cars with almost no extra space?
Conclusions:
What we know (pre-COVID):
there are more private cars registered in the city more vehicles are passing monitoring points (flow)
there are more miles being driven
no been a material increase in road space
What we don’t know:
Long term COVID effect
Here an article in the local press. In summary the argument is predicated on data that shows only 4 of the 150 traffic monitoring points reducing - without reference to wider trends, forthcoming house building, climate challenges or car based inequality.
The article is correct that macro, data-led policy is important when there’s a town the size of Falkirk being built in Western Edinburgh.
In a city with the same or less space as 22 years ago, geometry wins.
Addendum:
Having more traffic, particularly via single occupancy cars, flowing through any city is an outdated concept anyway!
Better outcomes might be:
Place
Capacity
Equality
Resilience
Health
Childhood
Prioritising traffic flow simply gets you…. more traffic.
It induces demand with all of the harmful outcomes for our communities, bus service and those who have no other option but to use a car.