Standing on top of the visitor centre at Thurrock Thameside Nature Park, you could be forgiven for being disappointed by the view: a large field of brambles. But just 10 years ago, the same view would have been even more disappointing: mountains of rubbish heaped up on one of Europe’s largest landfill sites.

For 50 years, the site absorbed waste belched out by Londoners. Now the only reminder of its past life is the odd piece of discarded metal.

Facebook Twitter Pinterest The park is home to some of the UK’s rarest inhabitants, including the shrill carder bee. Photograph: Gabrielle Horup/Essex Wildlife Trust

The park might look unloved, but the reserve is meticulously managed by the Essex Wildlife Trust (EWT) and provides a valuable home for some of the UK’s rarest inhabitants, including cuckoos, adders, water voles and the extremely rare shrill carder bee.

“This is the best view in Essex,” says Emily McParland, communications manager at EWT, who urges visitors to the site on the Thames estuary to “celebrate unglamorous landscapes”.

“Many people are unaware of just how valuable scrub is as a habitat. It is one of the most underrated habitats and some of our most iconic British species need scrubland to thrive, so that is one thing we try to educate our visitors about,” she says.

In the mid-1990s there were about 1,500 active landfill sites in the UK. Now there are fewer than 250, largely because taxes were introduced that made sending rubbish to landfill more expensive than incineration.

Facebook Twitter Pinterest The park was once one of Europe’s largest landfill sites. Photograph: Essex Wildlife Trust

Now scrubby landfills across the country are becoming significant refuges for rare species. There are 20,000 old landfill sites in England and 1,315 of them have at least one environmental designation on them, according to analysis of Environment Agency and Natural England data by Dr James Brand from Queen Mary University of London. A significant proportion – 11% – of sites of special scientific interest in England are built at least in part on old landfill.

“This isn’t surprising. It is likely in many cases that the land isn’t suitable for other uses due to the waste buried beneath it,” says Brand.

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The landfill that forms Thurrock’s scruffy 49-hectare (120-acre) hillock sits on top of a 1920s quarry, which provided building materials for the burgeoning capital. The mine closed in the 1950s and the city’s unwanted waste was brought back and dumped in the newly vacant space. At one point Mucking Marsh landfill, as the site was called then, took 660,000 tonnes of rubbish every year.

Facebook Twitter Pinterest A short eared owl visiting the park en route from Iceland. Photograph: Andy Rouse/2020Vision/Essex Wildlife Trust

Now it provides an important pit stop for short-eared owls from Iceland, nightingales from Senegal and song thrushes from Russia looking to refuel on bugs and berries before continuing their travels.

All this life is reliant on a layer of clay crust just 1.4 metres (4.6ft) thick, which sits on 30 metres of gurgling waste, weighing around 20m tonnes. The only building on site – the visitor centre – is held upright by hydraulic jacks.

Like most landfill sites, this crust is too thin to support trees because their roots would penetrate the black plastic the waste is wrapped in, potentially causing methane and toxic liquids to be released into the environment. This is why wildlife reserves on landfill sites are often left as scrub or grassland.

Thurrock’s transformation from rubbish dump to wildlife reserve came about from a £2.8m agreement between Enovert Community Trust – previously Cory Environmental Trust – and the London Gateway port operator, DP World, to improve wildlife sites along the estuary. The landfill stopped accepting waste in 2010 and as each section was sealed up it was released to EWT to look after. Once the clay top is complete, the EWT reserve will be 340 hectares – double the size of Regent’s Park.

Facebook Twitter Pinterest The park’s visitor centre is held upright by hydraulic jacks because of the thinness of the clay crust covering the waste below. Photograph: David Levene/The Guardian

Mucking Marsh landfill belches out enough methane gas to power around 10,500 homes. This potent greenhouse gas is released via a pipeline and then combusted to form CO2 and particulate matter before being released into the atmosphere. Enovert will manage the decaying matter until it stops producing gas, which is expected to happen in 2040. The decay of organic waste on landfills accounts for one third of UK’s methane emissions, so making sure landfills are properly sealed is key to minimising environmental damage.

Other grassy mounds along the estuary – such as those at Beckton and Rainham – have been formed in recent years. They might look like the remains of some iron age fort, but they too are stuffed full of modern man’s excesses and neatly capped off with a clay “pie crust” as if nothing had happened.

When David Attenborough opened Thurrock Thameside nature reserve in 2013, he said its transformation marked a “new chapter” in the Thames estuary. In the years following his visit, the number of plant species has increased from 48 to 91, according to EWT, with bee orchid, yellow rattle and bird’s foot trefoil all new additions to the site.

Facebook Twitter Pinterest Birds such as the stonechat use the brambles for nest-building and foraging. Photograph: Adam Jones/Essex Wildlife Trust

Whitethroat, stonechat, song thrush and linnet already use the brambles for nest-building and foraging, and in the coming years EWT plans to put down a seed mix of grain and millet to attract more farmland birds which have suffered substantial declines, including skylarks, corn buntings and turtle doves, which are currently heading towards extinction in the UK.

Reptiles such as the adder are also flourishing, overwintering in the undisturbed brambles and emerging in spring to warm themselves up on the grassy edges.

Thurrock Thameside is far from a manicured environment, but this is the sort of land nature needs, says Prof Karl Williams, director of theCentre for Waste Management at the University of Central Lancashire. “Land that is good for wildlife normally looks unkempt in our eyes,” he says.

“You’d be surprised how close landfill sites are to where you live. A lot of the time they are filling a hole in the ground and are restoring land to what it was before quarrying and mining. They cannot be developed on, so it allows nature to reclaim them and for species to come back.”

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