Our guide to putting sustainability front and centre of your infrastructure project, from Professor Richard Fenner, Director of the Centre for Sustainable Development, University of Cambridge.

1. Seek opportunities for multi-functionality of infrastructure systems

Multi-functionality in infrastructure refers to achieving more than one service or function from the assets we build. For instance in creating infrastructure that simultaneously minimises ecosystem damage, is energy and resource efficient and contributes to healthy, vibrant and cohesive communities.

Examples of integrated approaches could include: linking transportation, mixed use development and brown field regeneration encouraging biodiversity in town and city landscapes through the creation of blue-green corridors that integrate flood protection and water management functions with green infrastructure. In this way a single piece of infrastructure can deliver a range of multiple benefits beyond its primary function. Why is multi-functionality important?

Multi-functionality can improve resource efficiency, reduce the costs of construction and operation, minimise adverse social and environmental impacts. It also captures possible benefits from economies of scale. It represents an integrated approach in meeting service needs across a range of resource sectors. But for this to happen, agencies and institutions, particularly at the city level, need to work together in a coordinated way to achieve these potential multiple benefits. What is an example of infrastructure that provides multi-functionality? Sustainable urban drainage systems, like the ones in the Eddington development in Cambridge, UK, can provide additional green space and habitat (encouraging biodiversity), help sequester CO2 , trap pollutants on leaf surfaces and reduce the urban heat island effect, as well as add to the visual aesthetics of an urban area, providing recreation and amenity opportunities and even traffic calming measures.

2. Move away from siloed planning, based on consumption and disposal, toward more low-carbon solutions that reflect public preference and social need

Siloed planning is where infrastructure services are delivered independently by agencies and organisations who only work within their own resource sectors: water, energy, highways, housing, waste disposal and so on. Each infrastructure project needs to recognise the local context in which it will operate. This is because it will provide a unique set of opportunities and constraints in each location. Therefore, engagement with stakeholders and end-users is very important at the planning stage, so that the real needs of those being served are met. Infrastructure projects will be expected to reflect, for example, health and well-being, social cohesion, inclusion and equality. So before defining project outputs, needs should be defined at the outcomes level. This can lead to solutions that serve the local community in more innovative and sustainable ways. They are often also more affordable.

3. Prepare for increasingly complex threats to infrastructure.

Existing infrastructure systems are being overwhelmed because of an increase in natural disasters. Engineers need to predict potential futures and build according to these, for example when planning drainage systems for increased flooding. “Consider the $14 billion levees built in New Orleans since 2005 after Hurricane Katrina which, in a rapidly changing climate, don’t protect against category five hurricanes today” (Wallace-Wells, 2019, cited in Fenner, Sykes and Ainger, 2022).

4. Think beyond simply offsetting the negative effects of infrastructure and follow a more restorative and regenerative approach.

The aim is to stop infrastructure choices simply becoming ends in themselves. We should ask: is building a new asset the right decision in every context? Often less costly and lower risk solutions can meet the necessary service demand. For example, expansion of transport infrastructure may be unnecessary in the future if more people continue to work from home and on-line, significantly reducing the demand for travel.

5. Incorporate a critical appraisal approach to infrastructure projects. Engineers need to repeatedly review their infrastructure plans, spot potential issues before they arise and deal with them.

Engineers need to continuously evaluate their decisions against a wider set of criteria than the traditional ‘quality’, ‘cost’, and ‘time’. This requires being able to answer the question: ‘am I acting sustainability?’ This could also involve evaluating projects across wider issues of scale and boundaries, ethics, context, socio-economic purpose and impacts, and future timeframes. These are examples of a wider set of choice criteria by which a project is evaluated as ‘sustainable’. Delve deeper into the world of sustainable infrastructure development with Professor Fenner’s Cambridge Advance Online(Opens in a new window) course, Delivering Sustainable Infrastructure: Theory and Practice for Construction https://bit.ly/3GTHWSS