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The districts with the most toxic landfills in England and Wales

With over 1,200 toxic landfills masked underground across England and Wales, Uswitch was keen to discover which English and Welsh districts were home to the most toxic landfills in proportion to land area.
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The districts with the most toxic landfills in England and Wales header image
The districts with the most toxic landfills in England and Wales header image

With an ever-increasing need to dispose of waste, there are a lot of landfill sites dotted across the country, despite a desire to become more conscious of our carbon footprint. However, some are more hazardous than others, with many highly toxic landfills across the nation being described as ‘toxic timebombs’. But which districts in England and Wales are home to the most toxic landfills, rendering them most at risk?

Keen to unveil the answer to this worrying question, the energy experts at Uswitch sought to analyse the locations of the hundreds of buried toxic landfills across England and Wales, measuring the number of toxic landfills against the land area of each district. From this, we can reveal which English and Welsh districts are sitting on the most toxic landfills per km².

The districts in England with the most toxic landfills

The districts in England with the most toxic landfills listed with map
The districts in England with the most toxic landfills listed with map

The district of Sandwell in the West Midlands is revealed to be the area of England with the most toxic landfills per km². In total, Sandwell is home to 14 toxic landfills across the area of 85.56km², which equates to one toxic landfill per 6.11km².

Also situated in the West Midlands, the district of Walsall is revealed to be the area in England with the second most toxic landfills in proportion to area. To be precise, Walsall was home to 15 toxic landfills across 103.97km², equating to one toxic landfill for every 6.93km² of area space.

The district in England with the third most toxic landfills in proportion to area is Salford. Across the district’s area of 97.2km², there are 12 toxic landfills. This is equivalent to one toxic landfill per 8.1km² – the third highest figure.

Halton, which can be found in Cheshire, is the district with the fourth most toxic landfills in proportion to area, with one toxic landfill for every 8.21km². Specifically, there are 11 toxic landfills situated across an area of 90.32km².

Bolton District in Greater Manchester is home to the fifth most toxic landfills in proportion to area. Despite the district spanning an area of 139.79km², the 15 toxic landfills located in the area meant that there was one toxic landfill per 9.32km².

The London borough of Barking and Dagenham is home to the sixth most toxic landfills per km², despite only having four toxic landfills in the area. This is largely due to the fact that the district is so small, spanning an area of just 37.78km². As a result, Uswitch found that there was one toxic landfill per 9.32km² in the district.

The district of Manchester is home to the seventh most toxic landfills in proportion to area after our research revealed one toxic landfill for every 9.45km². Across the 115.65km² of area belonging to the district, there are 12 toxic landfills overall.

Situated in south west Hertfordshire, Three Rivers District has the eighth most toxic landfills in proportion to area. Uswitch found that across the 88.82km² of area in the district, there were nine toxic landfills in total, which equates to one toxic landfill per 9.87km².

Meanwhile, Suffolk’s Bury District is revealed to be home to the ninth most toxic landfills per km². Across the district’s 99.46km², you can find 10 toxic landfills, meaning that there is one for every 9.95km².

Rounding off the top ten districts with the most toxic landfills in proportion to area is the London Borough of Bexley, where six toxic landfills are in the 64.32km² covered. This means that there is one toxic landfill for every 10.72km².

The districts in Wales with the most toxic landfills

The districts in Wales with the most toxic landfills list and map
The districts in Wales with the most toxic landfills list and map

Cardiff (Caerdydd) is the district home to the most toxic landfills per km² in Wales overall. The district, which has an area of 149.44km² and is based in South Glamorgan, is home to 25 toxic landfills. This is equivalent to one toxic landfill for every 5.98km² in the area.

Flintshire (Sir y Fflint) has the second most toxic landfills in proportion to area. With a hefty sum of 54 toxic landfills spanning across the district’s 489.50km², there is one toxic landfill per 9.06km² in Flintshire.

Blaenau Gwent is the Welsh district with the third most toxic landfills relative to km². With 10 toxic landfills throughout the district’s area of 108.73km², Uswitch discovered that there is one landfill per 10.87km² in the district.

Caerphilly (Caerffili) was the district with the fourth most toxic landfills in proportion to area in Wales. There are 23 toxic landfills in the area, which spans 277.39km², meaning that there is one toxic landfill per 12.06km².

In fifth is the Vale of Glamorgan (Bro Morgannwg) in South Glamorgan. Across the 339.80km² that the district spans, you can find 27 toxic landfill sites, meaning that there is one for every 12.59km².

The Welsh district with the sixth most toxic landfills per km² is Torfaen, where there are eight toxic landfills across the district’s area of 126.24km². This is equivalent to one toxic landfill per 15.78km².

Merthyr Tydfil (Merthyr Tudful) in Mid Glamorgan, has the seventh highest number of toxic landfill sites per km², with six spread across the 111.96km² the district spans. This equates to one toxic landfill per 18.66km².

Wrexham (Wrecsam) is the district with the eighth most toxic landfill sites in Wales relative to the district area. There were 22 toxic landfills across Wrexham, with Wrexham spanning 503.77km². This means that for every 22.90km² in Wrexham, there is one toxic landfill site.

The Welsh district with the ninth most toxic landfill sites relative to the district area in km² is Swansea (Abertawe) in West Glamorgan. Across Swansea, there are 12 toxic landfills, which means there is one toxic landfill per 35.01km² in the area.

In tenth is Monmouthshire (Sir Fynwy), in Gwent, where you can find 18 toxic landfill sites across the district’s area of 886.04km². This means that there is one toxic landfill site per 49.22km² in the district.

Methodology:

  • Uswitch sought to determine the areas in the UK that have the most toxic landfills.

  • Utilising official Environmental Agency data, Uswitch were able to discover where these hazardous landfills are located.

  • By recording and analysing the location of each landfill, they created a ranking of the areas in the UK with the highest volume of toxic landfills in comparison to their land area.

  • There was a grand total of 1,286 toxic landfills included in this study.

  • The land area was sourced by using the Ordnance Survey Boundary Line data set.

  • After finding the area size of each specific district, Uswitch wanted to find the number of landfills to km². To do this, they divided the area size by the number of landfills. This allowed them to see which area had the highest volume of toxic landfills in comparison to their land area.

  • There was no recorded data for Scotland or Northern Ireland, so these countries were omitted from the dataset.

  • The data for this study was sourced from the ENDS report on the most toxic landfills in the UK. Uswitch sourced the data on 18/08/2021 and is accurate as of this date.