Many of Britain’s dismantled railways are rich in heritage, but they are not only relics of the past – they have a vital role to play in our futures, often acting as “wildlife corridors” that connect habitats, allowing the movement of species and supporting biodiversity at a time when multiple species are under threat. The intermingling of railway heritage with nature has created some truly special places and every mile of dismantled railway that nature has reclaimed has a role in carbon-uptake as well as in supporting wildlife.

But the ecological and environmental value of Britain’s estimated 10,000 miles of dismantled railways has not yet been fully recognised. National Highways has been seeking to demolish or infill dozens of legacy bridges forming part of the Historical Railways Estate, for which it is charged with stewardship. The process of infilling typically involves burying a bridge in 1,500-2,000 tonnes of quarried stone and concrete, and the carbon footprint of such schemes is enormous compared with sympathetic repairs. But there can also be subtle yet far-reaching consequences for local ecosystems – blocking routes used by wildlife for migration and foraging, as well as potentially destroying habitats.

A public outcry following National Highways’ widely-publicised infilling of Great Musgrave Bridge, Cumbria led to the Government pausing the programme and National Highways pursuing a stakeholder engagement exercise which has so far focused on the potential for some dismantled railways to be used for sustainable transport use, but largely ignored environmental and wildlife impacts – involving no organisations to represent ecological concerns.

The HRE Group – a national alliance of engineers, heritage and sustainable transport campaigners pushing for the conservation of the Historical Railways Estate – has conducted a desktop appraisal suggesting that, of the 59 HRE structures in England where proposed major works by National Highways are currently paused, nine are in Areas of Outstanding Natural Beauty, one spans a Site of Special Scientific Interest and 20 (34%) are in areas designated on the Priority Habitat Inventory for Deciduous Woodland. Of the 57 bridges across the UK earmarked for full infilling, 38 (67%) appear to span viable wildlife corridors which would therefore be blocked.

Examples of where National Highways infill schemes pose significant ecological threat are:

• At Church Road, Barcombe in East Sussex (photo left), National Highways proposed to infill a Victorian road-over-rail bridge with an estimated 1,800 tonnes of concrete and aggregate. The bridge spans a section of the former “Bluebell” (Lewes to East Grinstead) Line, which has become an important wildlife corridor lying adjacent to ancient deciduous woodland, connecting the Ouse Valley to Knowlands Wood, known to be used by rare fauna and flora. After a strong community campaign including national press coverage and questions asked in Parliament, National Highways has changed its position saying it no longer intends to infill the structure, though it has not entirely ruled infill out and continues to dismiss the bridge’s ecological value.
• At Little Smeaton near Doncaster, North Yorkshire, two bridges on the former Hull & Barnsley Railway (1885-1959) are threatened with concrete and aggregate infilling. Both bridges have designated Priority Habitat Inventory status (deciduous woodland) to both sides, and both are in green belt. One of the bridges (photo centre) would require an estimated 3,000+ tonnes of concrete and aggregate to infill due to it having a skew span built to cross three tracks. Even while the infill programme is meant to be paused, National Highways has cleared a 10m-wide strip of habitat in preparation for its infill scheme.
• The maintenance options for the three-arch Crows Castle bridge (photo right) are currently described as “under development”. The structure spans Notgrove Cutting Site of Special Scientific Interest in the Cotswolds Area of Outstanding Natural Beauty. It is noted for providing excellent exposures of part of the Middle Jurassic, Upper Inferior Oolite and is the most complete section of the Clypeus Grit in the Cotswolds, containing a rich fossil fauna and has been the source of several important ammonite finds. This key research site is of national geological importance.

We call on Baroness Vere, the Minister responsible for the Historical Railways Estate, to commission an independent and expert body to holistically assess the habitats hosted by dismantled railways, their viability as wildlife corridors and to recommend appropriate safeguards and mitigations.

Secondly, out of concern for its high environmental impact (including carbon footprint) we call on Baroness Vere to end National Highways’ practice of using concrete and aggregate infill as a “preferred option” anywhere. Where it is considered as a “last resort” we call for its environmental impact to be fully considered and mitigated.

Finally, we call on Baroness Vere to instruct National Highways – through a policy change – to seek, wherever possible, ecological, environmental and community benefit from these heritage structures – a more fitting legacy to the efforts made and lives lost in the construction of our nation’s railways.