The Transpennine Route Upgrade (TRU) programme has achieved the UK’s first fully sustainable track renewal at Cross Gates, using green steel, blended ballast, and low carbon concrete sleepers, significantly reducing the carbon footprint of railway construction. This milestone supports the electrification of the railway and demonstrates the programme’s commitment to environmental sustainability and carbon reduction.
In move to reduce the carbon impact of construction the Transpennine Route Upgrade (TRU) programme has delivered the UK’s first low carbon track renewals, utilising all three key material groups – green steel, blended ballast, and low carbon sleepers.
The renewal was successfully trialled at Cross Gates, as engineers from the TRU East Alliance completed five consecutive weekends of critical work to support the electrification of the railway.
Traditionally, track materials like ballast, steel rails and concrete sleepers contribute significantly to infrastructure emissions. The achievement at Cross Gates resulted in a 63% reduction in embodied carbon over 660 metres of track, and is a step forward in building a more sustainable network.
The TRU programme is committed to building and operating a railway that enhances the environment and looks for new way to achieve sustainable development to help maximise opportunities to serve customers and communities, ensuring progress towards a better, more sustainable future.
A key objective is to reduce the carbon footprint and cut whole life carbon, and by 2035, the programme aims to:
- Reduce the carbon used to operate the railway by 230,000 tonnes of CO2e – leading to a total saving of 6 million tonnes of CO2e over a 60-year period after work is complete.
- Reduce the carbon impact of construction by up to 30%.
- Reuse/recycle 90% of construction waste, 70% of operational waste, and 99% of all non-hazardous materials diverted from landfill.
The TRU East Alliance is committed to this aim and has worked closely with Network Rail’s Supply Chain Operations to source the material necessary to achieve this step forward in low carbon track renewals.
Lower carbon ‘green steel’ is produced with a significantly lower carbon footprint than conventional steel and manufactured using recycled materials and innovative low-carbon technologies such as electric arc furnaces powered by green electricity, helping to reduce bodied carbon by over 50%.
Blended ballast has been used in several places across the programme. Typically, blended ballast consists of a mixture of reusable ballast taken from track renewal projects (no more than 50%), which is then processed before blending with new ballast.
Low carbon concrete sleepers have also been used across the programme since 2024. The first installation took place at Osmondthorpe Lane in Leeds, where the team removed the existing track and 155 hardwood sleepers during the replacement of the railway bridge, and at Shipley Depot. The sleepers are manufactured by Sicut from plastic waste, and are fully recyclable, providing a lighter, longer lasting, more sustainable, and efficient alternative to timber sleepers.
The programme is also focussed on reusing sleepers, with sleepers supplied by the TRU West Alliance reused at Healey Mills SCO depot a quality test confirmed they were of good quality for slow moving/stationary trains. This resulted in a carbon saving of 16.5% from the Healey Mills SCO Depot baseline.
James Ramsden, TRU Alliance director said: “This trial highlights how thoughtful material choices and design innovation can make a tangible difference. It's a key step in our journey to deliver a greener, more sustainable railway for future generations.”
