Even though Crossrail is being built through heavily populated areas of London, it still has an impact on wildlife. The land surrounding our rail tracks and some of the areas where new Crossrail tracks, depots and stations will be built support a variety of wildlife including orchids, trees, snakes, lizards and frogs.
We are working hard to protect and improve the environment we touch. As part of the completed works, we are also exploring opportunities to encourage greater biodiversity at several locations along the Crossrail route, including:
- Wallasea Island
- Wallasea Island watervoles
- Rehoming wildlife
- Finsbury Circus trees
- Regenerating the River Lea
Following our official announcement in September 2012, Wallasea Island nature reserve is now under construction.
Around 4.5 million tonnes of tunnel excavated material from Crossrail will be used to create a landmark conservation and engineering scheme, on a scale never before attempted in the UK. It will provide a home for tens of thousands of migratory birds, and combat the threats from climate change and coastal flooding.
The Crossrail material is being used to re-engineer the arable landscape prior to breaching the existing sea defences to create the new wetland landscape. Crossrail’s transport strategy has focused on moving excavated material by rail and ship where possible, preventing the need for thousands of lorry journeys on Londons’ roads. The material from the western tunnels is being transported from the tunnel entrance to Northfleet in Kent via rail before being transferred onto ship for delivery to Wallasea Island. At the eastern tunnels entrance at Limmo Peninsula in east London, excavated material is being loaded directly onto ships. Material from the central London station worksites is being transported via road to a transfer facility at Docklands Transfer site on the River Thames where it is then loaded onto ships.
Gallery - construction milestones at Wallasea Island
Wallasea Island water voles
Water voles are known to inhabit most of Wallasea Island's main ditch and Soke Dyke systems and as our construction programme at the island includes extensive re-shaping of the existing water courses, the voles are being rehomed.
A total of 150 voles have been captured through organised 'trappings' and relocated under licence (see picture). In addition, over 8200 common lizards and 30 adders have been rehomed as part of the works.
Wild orchids, reptiles and giant eels have all been rehomed by Network Rail following the start of its works on behalf of Crossrail in the Stockley Junction area in West London.
Back in March 2012 works began that will allow Crossrail services to operate to and from Heathrow Airport. Ecological surveys conducted at the site had identified reptiles and amphibians and an initial relocation took place in advance of the works to avoid delays to the project. In total 46 protected slow-worms, 593 newts and five frogs from the Stockley area were relocated to new homes in August 2011, following consultation with the London Borough of Hillingdon.
Then, as construction began, a relocation operation kicked into gear as contractors cleared and lowered nearby Anderson Pond (see picture). It was then electro-fished, a technique which temporarily stuns fish, allowing them to be surveyed and returned to the water unharmed.
A total of 599 fish were safely caught and moved to a new home. Species found included tench, roach, rudd and bream, all of which were held in an aerated tank to recover before their relocation to Pondwood Fisheries near Maidenhead.
The real catch of the day was a European eel, which is a critically endangered species. It weighed an exceptional 5lbs and came in at 3ft long. It takes about 10 years for an eel to put on a pound so this one could be 50 years old.
During the site clearance 30 wild orchids were also relocated to similar habitat at Maple Lodge Nature Reserve in Hertfordshire.
A similar story also unfolded at our Old Oak Common worksite where pre-construction surveys discovered a colony of slow worms. Our first step was to tweak our detailed design to avoid the reptiles’ key habitat areas. The next phase involved the capture and relocation of the slow worms before the works began.
Fish rescues were also carried out from the docks at Canary Wharf and the Royal Docks at Connaught Tunnel. Over 500 fish were rescued and relocated from Canary Wharf and 337 fish were also successfully removed from the cofferdam at Connaught Tunnel. The species included bass, herring, flounder, bream, perch and eels.
Finsbury Circus Trees
Finsbury Circus is the City of London's largest area of green space and is also London's oldest garden dating from the 1600s.
Crossrail has been working with the City of London since 2006 to ensure that the layout and access arrangements for the worksite at Finsbury Circus will protect the mature London Plane trees in the gardens. The branches and logs from the five smaller trees that had to be felled are being used to construct habitat for invertebrates (such as stag beetles) within Finsbury Circus and other parks and gardens in the City of London.
Regenerating the River Lea
A regeneration project to create wildlife habitat and encourage biodiversity on the banks of the River Lea close was carried out close to a Crossrail worksite.
The project formed part of Crossrail Community Investment Programme designed to support the communities and environment neighbouring the Crossrail works.
A section of the river bank was cleared of invasive weeds, landscape, plant reeds and shrubs and a barrier erected to protect the plants while they establish themselves. The changes will encourage biodiversity and provide new habitat for wildlife including coots, moorhens and kingfishers. It will also make the canal look more attractive for people using the waterway.