Is Bristol A 20-minute City?

About the project

For Basemap the year of 2021 is that of “20-minute cities” and investigating whether the United Kingdom has any. Taking the 12 most populated cities and their residential populations Basemap will be analysing the access to essential amenities via public transport or walk within 20-minutes.

To begin the series we asked, “What is a 20-minute city?”, essentially, all of your needs should be met within a 20 minute journey from your home either by public transport or walking, this includes work, shopping, health, education and recreation. For a more detailed explanation you can read it here.

Each month we will focus on a different city and create 5 accessibility maps. To supermarkets, hospitals and GPs, primary schools, secondary schools, and public transport stops.

All the cities begin with a foundation of a detailed road and footpath network, for cities in Great Britain we used OS Highways, which is due to be added into DataCutter in February. On top of this, Basemap layered the public transport network, for consistency, public transport data will all be taken from Q4 2020, allowing for any drastic changes to happen in 2021 without skewing the comparison results.

For the origins, Basemap created a grid of points based on the city boundary and then found the Points of Interest (POI) within this boundary for each destination type. This means that the accessibility to these destination points could reach beyond the city boundary but for the scope of this series we are specifically looking at the accessibility within the city limits. Due to the different countries within this project, the Points of Interest was sourced from various places and will be referenced for each individual city.

The Bristol results are in…

Starting with the accessibility to Hospitals and GPs (Left) in Bristol, with 156 destination points the coverage is visibly vast. The lighter blue shade shows the accessibility of 10-minute walk or public transport and the darker blue shows how this is extended by going to 20 minutes. Resulting in 96.49% of the population able to reach a Hospital or GP within 20 minutes.

When comparing this to Supermarkets (Right) with four times as many destinations (631). The commercial venture is undoubtedly more accessible in the lighter green range with most of Bristol being able to access either a supermarket or convenience store within 10-minutes. This expansive accessibility doesn’t translate to the 20 minute range, being only 0.45% more accessible than Hospitals. Resulting in the slightly higher population percentage at 96.94% for supermarkets.

The school maps were specifically calculated with the students’ ages in mind, for Primary schools the calculation only included ages 6-10 and 11-16 for Secondary.
Primary and Secondary schools alike are accessible to majority of the corresponding population within 20-minutes, with more residents reaching Primary schools within 10-minutes potentially because there are more of these (105) when compared to the 54 Secondary schools. The calculations showed that 96.64% of 6-10 year olds can get to school in less than 20 minutes.

In comparison to the previous maps, Secondary schools are the least accessible when using public transport or walking, though this is not to say that the accessibility is low, as 92.26% of 11-16 year olds can access a school.

Public Transport stops and routes are the backbone of all the previous calculations, this final map shows the accessibility to a 1279 Public Transport stops within 400m walking distance from residents’ properties. The lack of stops in the north of the city is reflected in all the other maps. Current accessibility stands at 67.48%. If Bristol were to increase their coverage, with more routes and stops connecting to the north of the city it would improve accessibility. This area of the city is industrial, therefore adding stops wouldn’t necessarily improve access to hospitals or schools etc. but it would improve access to jobs in that area, which is still an important aspect of a 20 minute city.

Below is the table that will be filled in each month.

This includes the overall population of each city as well as the percentage of the population who can reach the various destinations within 20 minutes. The destination headings act as a key with the corresponding colours on the maps.

Come back next month when we will be looking at Belfast!