Infrastructure: can roads ever be sustainable?

Yet they can also support economic activity, connect communities and provide access to essential services. The question is whether these benefits can outweigh the environmental impacts.  
 

Roads are not sustainable by default. Their sustainability depends on how they are designed, built and operated. When managed effectively, they can support safer transport networks, improve connectivity and reduce environmental impacts over time.
 

Progress is already possible. Between 2021 and 2024, ALiS, a motorway operator in France, reduced Scope 1 emissions by 58%, demonstrating how existing road assets can improve sustainability performance while continuing to provide essential services. Scope 1 emissions are the direct greenhouse gas emissions from sources a company owns or controls.

Managing carbon across the asset’s life 
 

The sustainability profile of a road is often determined long before the first vehicle uses it. Developers can therefore focus on reducing the carbon intensity of materials by favouring options such as low-carbon concrete and recycled steel. 
 

In addition, construction processes themselves can increasingly be electrified and powered by renewable energy sources, helping to reduce direct emissions on site. Logistics also play a meaningful role, and shifting material transport toward more efficient modes, such as rail, can further cut the overall footprint.
As transport systems evolve, roads must also be designed with operational transition in mind. Future-ready infrastructure integrates electric vehicle charging capabilities as a standard feature rather than an afterthought. 
 

At the same time, improving traffic flow through smart management systems can help minimise congestion and associated emissions. There is also a growing opportunity to utilise road corridors for renewable energy generation, for example by deploying solar installations along motorways, contributing to cleaner operations over the asset’s lifetime.
These measures are not simply environmental improvements; they may also help protect the long-term relevance and value of road assets as transport systems evolve.

Safety and social impact

Safety is usually viewed as a social issue, but it is also an investment issue. The adoption of smart monitoring and digital systems can significantly improve incident detection and response times, enhancing overall user safety. Reductions in fatalities and serious accidents not only lower liability risks but also strengthen public trust and acceptance of infrastructure projects. 
 

Well-designed roads can improve access to jobs, education, healthcare and essential services, helping strengthen economic participation and regional development. Construction and operation can also support local economic development through employment, skills development and procurement opportunities for local businesses. 
 

However, roads can also have adverse social impacts, including community severance, displacement of households and businesses, and potential impacts on indigenous peoples and cultural heritage. A sustainable approach therefore requires robust stakeholder engagement, careful route selection, avoidance and mitigation of social impacts and fair compensation where impacts cannot be avoided. 
 

A road can be considered to deliver net positive social outcomes where these broader social benefits demonstrably outweigh residual adverse impacts over the asset's lifecycle. A road should not be considered sustainable simply because it improves mobility.

Biodiversity and resilience

Environmental outcomes are often shaped before construction begins, as design decisions have long-lasting consequences. 
 

Incorporating features such as wildlife crossings, tunnels, and sensitive routing can help preserve ecosystems and maintain biodiversity. Efforts to restore habitats and actively manage biodiversity can further offset environmental impacts. 
 

In parallel, robust mitigation strategies are needed to address land use changes and protect water resources, ensuring that environmental risks are properly managed.

Making existing roads more sustainable

Sustainable road investment is not only about building new assets. In many cases, improving existing roads may deliver greater environmental benefits than constructing new ones. 
 

The A28 Rouen–Alençon motorway in France is one example. The motorway, operated by ALiS, illustrates how an existing road asset can move towards a more sustainability-orientated operating model. 
 

The company sought to improve the sustainability performance of a traditionally carbon-intensive infrastructure asset through decarbonisation initiatives, stronger governance and engagement with regional stakeholders. It also focused on reducing operational emissions, integrated biodiversity considerations and aligned its long-term strategy with climate objectives, while continuing to provide important economic benefits and social connectivity. 
 

Measures included replacing fossil-fuel boilers, electrifying operational vehicles, buying more renewable electricity and installing photovoltaic systems for on-site use. 
 

Between its 2021 baseline and 2024, ALiS recorded a 58% reduction in Scope 1 emissions and a 48% reduction in location-based Scope 2 emissions. Scope 2 emissions are the indirect greenhouse gas emissions from the energy a company purchases.

Final thoughts 

The environmental and social impacts of roads are significant and must be managed accordingly. But they should not be excluded automatically from a sustainability perspective.
 

When planned, financed, built and operated with a long-term focus on resilience, decarbonisation, nature and social value, they can play a legitimate role in a sustainable infrastructure portfolio.
 

Roads can provide investors with long-term, stable and predictable cash flows, underpinned by their essential role in supporting economic activity and connectivity. 
 

However, maintaining long-term asset value requires the proactive management of sustainability-related risks and opportunities throughout the asset lifecycle.

Now read our Sustainability Update 2026.