Almost 40,000 birds are now overwintering on Wallasea Island in Essex, a nature reserve created using millions of tonnes of soil excavated during the construction of London’s Elizabeth line.
Around three million tonnes of earth were transported from London tunnel works to the island, where it was used to raise ground levels and help form wetlands. The RSPB bought Wallasea in the mid-2000s and began restoring it by breaching the sea wall in 2015, allowing tidal water to return for the first time in 400 years.
Using the imported soil, the RSPB built islands, lagoons and salt marshes that now provide vital habitats for wetland birds and help protect nearby communities by absorbing flood waters. Once largely devoid of wildlife, the site now hosts record numbers of birds, including 800 avocets, over 10,000 knot waders, nearly 3,000 grey plovers and a similar number of bar-tailed godwits.
Site manager Rachael Fancy said the area has transformed from what looked like a construction zone into a thriving sanctuary filled with birds. RSPB managers described the project as proof that major infrastructure and nature conservation can work together, calling it “a win for nature and people”.
