Chalk from a railway tunnel is becoming a home for wildlife

Beside the M25, chalk dug from an HS2 tunnel is helping turn former farmland into a place for wildflowers, butterflies and water voles.

New reporting from the Western Slopes project in Hertfordshire describes wildlife already using the young habitats. Grassland, ponds and wet meadows are taking shape across a 127-hectare site near the southern entrance to the Chilterns tunnel.

The idea starts with the soil. Thin, nutrient-poor chalk supports many flowers that struggle when vigorous grasses take over richer ground. Keeping excavated material nearby also avoids carrying it away.

The project’s design paper describes keeping natural drainage routes and creating varied ground conditions, rather than smoothing everything into one uniform slope.

This is still a developing landscape, and public paths are not yet open. Its progress cannot settle the wider environmental balance of HS2.

But there is something useful to learn here: planning around the material already on site can create new habitat. The returning insects and wetland wildlife show that some of that work is already taking root.

Sources

• The Guardian — field reporting from the Western Slopes
• HS2 Learning Legacy — habitat design and drainage