Resilient infrastructure systems – are we there yet?

February 2023

This month’s Smart Infrastructure Blog brings into focus the importance of understanding and managing key challenges in relation to critical infrastructure in construction. CSIC Senior Research Associate Manu Sasidharan calls for incorporating resilience consideration into the planning and decision of the infrastructure and integrating digitalisation into asset management practices to respond to potential infrastructure failure.

Infrastructure systems – namely transport, water supply, power transmission, gas pipelines and telecommunications networks – are crucial to the seamless daily operation and continuous development of society. The world’s urban population is projected to grow by 2.5 billion in 2050, reaching 68% of the total global population. Consequently, city and infrastructure authorities are currently forced to increase capacity, resilience and performance while dealing with the pressing challenges of deteriorating infrastructure, the changing and uncertain climate, and increasing costs in the face of constrained budgets. 

Managing infrastructure facilities is a challenging task due to the interdependencies (geospatial, physical and logical) and hence the possible cascading effects (…). Knowledge of the ability of  critical systems to respond and recover from such disruptions is key to identifying any climate resilience measures. Dr Manu Sasidharan CSIC Senior Research Associate, Department of Engineering.

In particular, climate change is projected to have a significant impact across the UK, chiefly in unusually heavy precipitation events, which is expected to be the salient climate change risk to all UK sectors. For example, some 6000 km of the UK’s railway network (including one in 20 bridges) is predicted to be at high risk of failure due to flood by 2080.  Several isolated days of intense rainfall in London in July 2021 resulted in a one-in-50 to a one-in-100-year flood event, resulting in the suspension of eight underground lines, and the closure of multiple underground stations and widespread damage to the city, with the cost expected damage to exceed £100m. More intense rainfall will also increase the frequency of sewer flooding and combined sewer overflow events. In the absence of further adaptations, the growing population and high climate change scenarios will result in widespread water deficits which will be largest in the southeast and north of England. Understanding and managing these key challenges in relation to critical infrastructure is crucial for achieving the UN-mandated Sustainable Development Goal 11 of ‘making cities inclusive, safe, resilient and sustainable’.

All UK infrastructure sectors have identified the future failure of another infrastructure sector as a risk to their networks. A one in a 1000-year flood in the Thames catchment alone is predicted to disrupt the wastewater treatment infrastructure serving over seven million people, the water supply infrastructure serving over 10 million and the telecommunications infrastructure serving over nine million; the impact of this may be even higher in an uncertain climate future. Managing infrastructure facilities is a challenging task due to the interdependencies (geospatial, physical and logical) and hence the possible cascading effects brought by the failure of one infrastructure asset to other facilities and services. For instance, cables, fibre optics, roads, railways, pipes and other infrastructure, even if not physically connected but if running in parallel along the same route, could experience cascading effects with a single event, disrupting multiple services. Knowledge of the ability of  critical systems to respond and recover from such disruptions is key to identifying any climate resilience measures. It involves incorporating resilience considerations into the planning and design of new infrastructure and strengthening the existing systems through retrofits and upgrades. To do that, it is necessary to take a comprehensive asset-planning approach that includes risk management. For instance, CSIC’s recent work presented a risk-informed approach for bridge management while dealing with uncertain climate futures. The study showed that railway bridges in southeast England could be at significant risk of failure, even in the low-emission climate scenario of RCP2.6.

While the understanding of risks to individual infrastructure sectors has improved, the impacts of climate change are expected to be amplified by the interdependencies between these sectors. Too often assumed resilience and operation are not there when needed, but a minimal investment to establish the condition of key strategic assets (e.g., fibre optic cables, bridges, roads, pipes) very often avoids costly reactive incident recovery. It is no longer sufficient to just identify strategic assets but to verify their operation and condition on a continuous and proactive basis. This requires communication and collaboration between asset managers on an unprecedented scale. The development of digital technologies such as the Internet of Things and Digital Twins provide new opportunities to enhance infrastructure resilience. Infrastructure companies are collecting vast amounts of data.  Because of this, we can now exploit advanced data analytics and artificial intelligence tools to model and understand the complex relationships, dependencies and evolutionary behaviour of these networks and their performance. By integrating digitalisation into asset management practices, critical systems can be monitored in real-time and quickly respond to potential disruptions. Infrastructure resilience is crucial for sustainable development and ensuring a better future. It nevertheless requires a multi-stakeholder approach, with governments, infrastructure owners/managers and communities working together to build and maintain resilient infrastructure systems.
 

References:

UN (2019) World's population projection in urban areas

R.J. Dawson et al. (2018)A systems framework for national assessment of climate risks to infrastructure

JBA Trust (2021) A retrospective look at London surface water flash floods

Pant R et al. (in press) Critical infrastructure impact assessment due to flood exposure. J. Flood Risk Management. 11, 22–33