Showing posts with label sprawl. Show all posts
Showing posts with label sprawl. Show all posts

Sunday, 12 February 2017

English Green Belt Atlas, Version 3

In 2015, after being posed the question by geodata guru Bob Barr, I decided to attempt to calculate the percentage of land in each local authority in England that was designated as green belt, using the official data from DCLG. This resulted in version 1 and 2 of my green belt atlas - a spare time project that I hoped people might find useful and informative. According to my calculations, 186 of the 326 local authorities in England contain at least some green belt land (that's 57%) but the amount within each area varies a lot, as you can see in my spreadsheet. For example, Sevenoaks, Epping Forest and Tandridge (below) all have more than 90% of their area as green belt, in contrast to (e.g.) 47% in Wirral and just over 5% in Bristol. I'd also be interested in the correlation between this data and house prices, or house price growth, if anyone is up for it (looking at you, Tom Forth).

This is my estimated figure, but I think it's pretty accurate

I've used the latest green belt data (2014-15) for this version

Surrounded by green belt but not much within the boundaries

I was prompted to go back to this after the release of the Housing White Paper last week and my last post on buildings in the green belt. Should we build all over the green belt? Definitely not. Should we consider building on little bits of it? Maybe. But before any of that I think it's useful to understand where and what it is, which is what prompted me to look at all this in the first place. I've uploaded all the individual map files to a separate Google Drive folder but if you're too busy to click, here are a few more.

The 'overboundedness' of Leeds' urban fabric is evident here

I find the North Warwickshire green belt split interesting

Manchester's green belt area is also interesting - airport in it?

My calculations suggest St Albans is more than 80% green belt

Hounslow - about a fifth of this is green belt

This surrounds Cambridge pretty neatly


Click to see all 186 maps

If you look at the folder with all the maps in it you should see that the figures all seem pretty accurate based on a visual comparison but there are a couple where I'm not 100% sure the figures seem right, but it might just be me. Either way, feel free to get back to me if you spot something that doesn't seem right.

This figure looks a little high, but it might just be my eyes

A London Borough with more than 50% of land designated as green belt

Sheffield is 25% green belt (not to mention part of the Peak District National Park)

York's green belt: note the little non-green belt part to the SE

That's all for now. Like I said, this was motivated by a personal interest in the topic and my desire to share useful information on an important issue. If  you want to use any of the maps, feel free. Or, if you want to get in touch if you've spotted an error then please do. If you're looking for an interactive web map of the green belt, then you have a choice: the Telegraph version, my CARTO version, or my Google search and zoom version.

The easy-to-remember link for the full set of images is http://bit.ly/greenbeltatlas3


Methods: this was another QGIS Atlas project, and more details of the method can be found in the footnotes of the original post. The only difference this time is a slightly different style, I've added in the local authority names and boundaries, plus some place names. But you'll notice if you look through the images that the number of labels differs by area - I could fix that but it would take too long for a spare time project like this. However, I think it does help with orientation. This version was done in QGIS 2.14. The files are all 300dpi PNGs and you are free to use them as you wish. 

Wednesday, 8 February 2017

Buildings in the Green Belt

The publication of the Housing White Paper yesterday prompted me to complete something that had been on the back burner for a while - mapping the buildings on England's green belt (or green belts, if you prefer). Before going any further, this isn't a post advocating building on the green belt but rather I wanted to explore the extent of buildings that are already there, in the hope that it might help enlighten me and others. I've previously written about green belt data and tried to figure out how much of each local authority is green belt, so this continues my interest in this area. First of all, here's a little map of buildings on the green belt around Bristol. If you want to download the 'buildings in the green belt' shapefile, scroll to the bottom of this post.

The Bristol and Bath green belt - perhaps not as empty as you might think

If we zoom in a little more you can see a little bit more of the detail of the pattern of development in the green belt. I'm not sure how much people know about the level of building in the green belt, but I did note that the Housing White Paper quite rightly pointed out that 'parts of it are not the green fields we often picture' (p. 28). The zoomed in area below is near Bath.


Part of the green belt around Bath

The point here is not to say that there is a particularly high level of development on the existing green belt, or lots of buildings in absolute terms, but rather to show that there are places within the green belt which are perhaps already more built up than some accounts in the media might suggest.  Many news stories on 'green belt' also often have pictures of lovely green countryside that is not actually green belt. Housing experts and planners are already aware of this, of course, and much of the development can be traced back to before the green belts existed, so this is in part an educational and visual exercise in mapping it all. The next few images cover some other urban areas across the country, starting with Oxford.


Buildings in the Oxford green belt

Buildings in the Cambridge green belt

Buildings in the Metropolitan green belt

Guildford (bottom) and Woking (top) area green belt

Buildings in the North East green belt

Buildings in the York green belt



In the final buildings in the green belt' map below I have just shown buildings without the green coloured green belt backdrop. This also gives you an idea of the level of building in the green belt, although it isn't very high.

Bear in mind that there still aren't that many green belt buildings

Finally, in order to put things in a bit more perspective, I've done a zoomed in map of the Gloucester green belt area showing those buildings which sit on green belt and those that don't. I have chosen this because I think it helps emphasise how successful the green belt has been in some places in relation to achieving the aim of controlling urban growth.


Gloucester green belt and non-green belt buildings

Data notes: I downloaded the most recent green belt shapefile from the DCLG and then got the building polygon data from the Ordnance Survey open data web pages - the OS OpenMap Local product. There is green belt in 14 different two letter OS tiles so I just extracted building data where it intersected the green belt. I then merged this into a single file. If you're looking for building data for your area, you might find some on my buildings page, where I have joined data for major urban areas and also added the local authority each building sits within. If you just need to know which tile to download, check out my tile finder below. Want to play around with and map this data yourself? I've made a 'buildings in the green belt' shapefile available for anyone to use. There are undoubtedly some small errors in the dataset, but I've used the DCLG file in good faith here. Note that in some places you'll see a large built up cluster in areas of green belt - as in the case of the West Midlands map and Kenilworth above.

Use my interactive map to find out which data tile you need