In this blog post, I'll discuss how I map the Campaign for Real Ale (CAMRA) branches using Leaflet and data from the Office for National Statistics (ONS). Please note that this blog post is a work in progress, and I will be making updates to improve its accuracy and implementation.
Having used various mapping frameworks, libraries, and postcode data in the past, including Leafletjs, QGIS, and the Office for National Statistics Postcode Directory (ONSPD) data, I became involved in a CAMRA project to map branch boundaries. Graham Donning, a longtime CAMRA officer, emailed us a Discourse (CAMRA's forum) post about the project, in which Phil Vickers from the Administrative Office of Staffordshire had already used QGIS to map the West Midlands region, consisting of 26 branches.
Based on this, I utilized the website Find that Postcode to gather GeoJSON coordinate data. Find that Postcode utilizes data from the Office for National Statistics, Ordnance Survey, and Royal Mail. I cross-referenced the Office for National Statistics Postcode Directory to manually correlate wards and local authorities to CAMRA branches. With the assistance of a quick NodeJS script I wrote, I was able to create a quick example showcasing the current 9 branches within the Greater Manchester region. Please note that there may be some caveats and errors in the data.
As part of my future plans, I intend to gather the postcodes that CAMRA considers under the authority of branches. I will incorporate GeoJSON coordinate data from Mark Longair's blog post on "Open Data GB Postcode Unit Boundaries" into my current codebase with minimal adaptations.
For the Central Manchester branch, I am currently using an INACTIVE ward, E05000697, which was active from January 2009 to May 2018. Unfortunately, I could not find any instances of Office for National Statistics Postcode Directory data for North East Cheshire (pertaining to the High Peak, Tameside, and North East Cheshire branch), South Manchester (for the Stockport and South Manchester branch), or the entire South-East Lancashire branch. This lack of data can be explained by the fact that the South-East Lancashire branch only existed as a parliamentary constituency between 1868 and 1885, which predates CAMRA's establishment in 1971.
You can currently access the website showcasing the branch map here: https://camra-branches.netlify.app/
To view the code for the project, please visit: https://github.com/Sean12697/CAMRA-Branch-Map