Hybrid locomotive for work on the track

Sustainability in rail and civil engineering focuses on reducing environmental impact across the entire lifecycle of infrastructure. This includes using emission‑free equipment, circular and recycled materials, and designing assets with a longer lifespan and lower maintenance requirements. Reusing structural components—such as circular viaduct beams or recycled copper contact wires for overhead lines—significantly reduces CO₂ emissions while conserving valuable raw materials.

CO₂‑reduction is achieved through a combination of clean construction methods and material innovation. Key strategies include:

• Deploying zero‑emission machinery such as electric cranes, electric rail‑road vehicles (Krols), electric vans and battery‑powered locomotives.
• Integrating circular concrete, geopolymer concrete, and recycled materials to lower embodied carbon.
• Collaborating across the supply chain — from client to contractor to materials supplier — to scale circular and low‑carbon solutions.

These measures not only reduce carbon emissions but help create more resilient, future‑proof infrastructure.

Infrastructure projects increasingly rely on advanced sustainable technologies, such as:

• 100% recycled copper contact wire, reducing CO₂ emissions by up to 92%.
• Geopolymer concrete, offering 50–80% CO₂ savings compared to traditional mixes.
• Electric and battery‑powered locomotives for maintenance and logistics.
• Circular overhead‑line foundations and poles made from low‑impact concrete.
• The Energy Bank, an innovative click‑and‑go substation that captures and reuses regenerative braking energy.
• Circular viaduct and bridge concepts, enabling reuse instead of demolition.

These innovations drive measurable environmental benefits throughout the asset lifecycle.

Zero‑emission equipment refers to machinery that operates without producing exhaust gases, typically powered by electricity or batteries. Examples include:

• Electric locomotives and battery locomotives
• Electric cranes and rail‑road (Krol) vehicles
• Electric vans and support vehicles

This equipment eliminates local emissions, improves air quality around work sites, reduces noise pollution and helps clients comply with increasingly strict sustainability requirements.

By 2050, the infrastructure sector aims to be fully climate‑neutral. This future includes:

• A robust, climate‑resilient infrastructure network designed for extreme weather.
• A fully emission‑free construction fleet.
• Circular material chains where components are reused at scale.
• Rail as a leading sustainable mobility system, supported by smart energy management and low‑carbon construction methods.
• Infrastructure that integrates nature, supports biodiversity and ensures safe mobility for everyone.

The transition is already underway, driven by innovation, collaboration and long‑term thinking.

Railway maintenance refers to all activities required to keep rail infrastructure safe, reliable and in optimal condition. This includes tracks, switches, overhead lines, sleepers, ballast, power supply, cables, ducts and signalling systems. Routine inspections and major renewal activities such as rail grinding, tamping and ballast maintenance are essential to ensuring long‑term track performance. Asset management plays a crucial role in rail maintenance.

The purpose of railway maintenance is to ensure the safety of passengers and train operations, prevent failures and delays, extend the lifespan of rail assets and avoid costly repairs by resolving issues early. Maintenance is vital for keeping high‑usage rail networks reliable and efficient, reducing disruptions and supporting sustainable rail operations.