Seven Challanges for Sustainable Infrastructure

Seven Challanges for Sustainable Infrastructure

- a blog article by Professor Richard Fenner

Delivering sustainable infrastructure is a big and, some would say, vague ambition. There is a lack of consensus on what this means in practice: ranging from merely specifying low carbon concrete and (wrongly) thinking the job is done, to considering a much wider approach across a range of social and environmental themes. However, underlying the aspirations for achieving sustainable infrastructure are a series of very tangible and critical challenges that provide a sharper and more specific focus that will drive the changes needed. Seven of these challenges are summarized briefly below.

1. Providing infrastructure services within  rapidly reducing carbon budgets

An important issue is to move from focussing on targeting carbon emissions to achieve net zero carbon by 2050 to working within a fixed carbon budget set for either specific infrastructure sectors (e.g. roads) or locations such as individual cities - if the world is to stay below 2 ^OC warming.

Current infrastructure projects are failing to meet this critical constraint. For example, it has been shown [1]  that under current policy housing alone would consume 104% of England’s cumulative carbon budget (2.6/2.5 Gt (under a 50% chance of <1.5^oC scenario). It has been estimated that all flights through an expanded Leeds Bradford airport by 2050 would take up almost double the entire carbon budget of the city of Leeds as a whole [2].  In 2020 Heathrow’s expansion was ruled unlawful for disregarding the Paris Climate Agreement which, if it went ahead, would mean aviation alone would account for nearly 30% of London’s carbon budget [3]. To stay within the 6^th carbon budget covering the period 2033-2037 (published in 2021) a 3rd runway, (adding another 7 MtCO2 or more per year), would mean that – in order to meet legally binding targets – most other UK airports would be required to close [4].

These examples have very serious implications for infrastructure as it will be vital to deliver services within these carbon budgets rather than focussing on end point targets, as it is the pathway to zero carbon that matters more than a particular date when we hit zero emissions.

2. Achieving net gain in biodiversity

Over 40% of UK species have fallen since 1970 and 133 species have been lost from the UK (mostly in the last 10 years). Estimates suggest¹ the conversion of agriculture and undeveloped land to urban development equates to an average 5.7% loss in species richness in the areas being developed. For housing expansion alone not to conflict with England’s 2030 wildlife abundance targets, Biodiversity Net Gain and species mitigation policies  will have to fully compensate for these losses. At present less than 30% of species mitigation measures have been demonstrably successful at preventing harm to wildlife from new housing [5].

The challenge is to incorporate greater use of green infrastructure and nature-based solutions in infrastructure projects. Yet the UK’s Natural Capital Committee has criticised the National Infrastructure Commission for failing to address the opportunities green infrastructure provides [6].

3. Working within resource limits

Globally 65% of total aggregates and 20% of metal materials are consumed in the construction sector and construction is responsible for the consumption of 60% of raw material. Even supplies of materials as mundane as sand are beginning to cause concern. The most-extracted solid material in the world, and the second-most used global resource after water, sand is an unregulated material used extensively in nearly every construction project on Earth. And with 50 billion metric tons consumed annually sand depletion is on the rise[7].

It’s just a matter of time before civil engineering organisations need to prepare themselves for a world where basic raw materials may be in short supply. This is a foreseeable constraint on future infrastructure activity – we really do only have one planet.  Responding to this requires adopting principles of a circular economy which seeks to remove pollution and waste, whilst keeping materials in use for as long as possible.

4. Delivering social value and serving communities

The services provided by infrastructure are vitally important as long as they address real needs. These include reducing inequalities, providing fair and affordable access, and delivering multiple outcomes (beyond the primary purpose of the investment). Public sector projects already have an obligation to demonstrate how they are adding additional social value (under the 2012 Social Value Act). This requires active involvement with stakeholders where solutions are co-generated with those who will experience and use the services being provided.

5. Responding to the  Sustainable Development Goals (SDGs)

Infrastructure directly or indirectly affects all 17 Sustainable Development Goals (2015-2030) including over 70% of the related targets. For projects to contribute to delivering the SDGs economic, social and environmental sustainability must be integrated at the earliest stages of infrastructure planning in a way that considers the interlinkages between different systems and sectors throughout the entire infrastructure lifecycle [8]. The SDGs provide a useful internationally accepted framework to guide future engineering actions   and test the efficacy of infrastructure provision, although some have reported that the built environment sector has lagged behind other sectors in responding to these challenges [9].

6. Managing ageing assets

In many parts of the world infrastructure systems are reaching the end of their intended design life and in some cases exceeding it. This can lead to unsafe bridges, inadequate flood defences, decaying tunnels and pipelines and water treatment facilities and power supply systems operating beyond their intended capacity. Much is being done to address these ageing assets and many opportunities exist in developing refurbishments and replacement to provide smarter, more efficient and lower carbon ways of delivering improved services. However investment remains low.

7. Speeding up change

As former ICE President Rachel Skinner has pointed out [10] , time is against us and the changes necessary to address the above challenges need speeding up. This is perhaps the biggest challenge of all. That is to be accountable today and ask questions to identify what our contribution is, what is mine to do, and what is yours?

Reacting to these seven challenges requires always questioning the easy option of just repeating what we did yesterday. Sustainable infrastructure is about the way we plan, design and construct and then operate and, importantly, use it.

To find out more about the tools and methods available to respond to these challenges  at every stage of infrastructure project delivery, read the recently revised  second edition of Sustainable Infrastructure – Principles into Practice in printor as an eBook.