05-12-2024 | Posted by Joaquín Martí
Let us start by stating a few unarguable truths. The Earth’s climate is changing. And the change is being driven by the warming caused by human activities, essentially the release of greenhouse gases, such as carbon dioxide and methane, by the transportation, power, and industrial sectors.
As stated by Bill Wallace in his recent book “The Great Civil Engineering Overhaul” (ASCE, 2024), we civil engineers are part of the problem, as we plan, design, build, and operate the facilities and systems that produce those emissions. But we could and should now be part of the solution: replacing fossil energy systems with low- or no-carbon-emitting systems, using materials with low embodied carbon, and designing and building infrastructure projects that are resilient and adaptive to changing climate conditions.
So far civil engineers have not been fast to respond, and it is understandable. The stationarity of the climate is deeply ingrained in our minds and embedded in practically all codes and standards. Moreover, the foreseeable rate of change of the climate must be considered in the context of the design life of the structures and facilities that we deal with.
In any case, we all have a problem, a growing problem that will not go away unless something is done about it. Thus, it is useful to review some of the aspects that will need attention.
Increased temperatures. Higher temperatures can affect the performance of construction materials, think of asphalt for example. Structures like bridges and railways may experience increased thermal expansion, requiring more robust expansion joints and other accommodations.
Sea level rise. Increased sea levels lead to coastal erosion, threatening coastal infrastructure such as roads, bridges, and buildings. Also, existing flood defences may become inadequate, necessitating upgrades or new construction of seawalls, levees, and flood barriers.
Extreme weather events. More intense and frequent storms can cause severe damage to infrastructure, buildings and other structures, which may have to withstand higher wind speeds and water loads. On the other hand, increased rainfall and more intense storms increase flooding risks; urban drainage systems, stormwater management practices, and floodplain regulations must be improved.
Principia has already been active in several projects accounting for climate change, in areas like coastal flooding, effects of wildfires on bridges, requirements for an overwater hotel in the Caribbean, etc. Overall, climate change demands a proactive approach in civil engineering, combining innovative design, adaptive management, and sustainable practices to ensure resilience and longevity. For civil engineers, it may not be very urgent, but it is important; hence we must act, perhaps slowly, but surely. The recent floods in Valencia are a reminder of this importance.
Hydrological changes. Changes in precipitation patterns affect water availability, requiring more resilient water supply systems and incorporating water conservation techniques. Increased rainfall and altered river flows can affect the safety of dams and reservoirs.
Soil and foundation stability. Changes in precipitation and temperature affect soil moisture and interstitial pressures, impacting the stability of foundations and slopes. And, in Arctic regions, thawing permafrost can destabilize foundations, roads, and pipelines.
Energy infrastructure. Higher temperatures increase the demand for cooling, affecting the design and capacity of power plants and energy distribution networks. Renewable energy generation impacts the grid and storage requirements; also, changing weather patterns affect the performance and reliability of renewable sources like wind, solar, and hydropower.
Transportation infrastructure. Extreme heat can cause pavements to soften and rail tracks to buckle. Increased flood risks and changes in river flows require bridges that can withstand higher water levels and faster currents.
Urban planning and development. Urban areas need to be planned with resilience in mind, incorporating green spaces, sustainable drainage systems, and robust building codes to handle extreme weather. And sustainable construction practices are needed to reduce carbon footprints and enhance durability.
Disaster preparedness and response. Engineers must work closely with disaster management professionals to develop emergency response plans and design infrastructure that can facilitate quick recovery after disasters. Redundant systems and infrastructure can help ensure that critical services remain operational during and after extreme weather events.
Adaptation and mitigation strategies. Civil engineers play a crucial role in both adapting infrastructures to withstand the impacts of climate change and mitigating its effects by reducing greenhouse gas emissions. This involves developing materials and construction techniques that are more resilient to climate change impacts; incorporating sustainable practices in all phases of construction, from planning and design to operation and maintenance; and advocating for and adhering to updated building codes and regulations that consider the long-term impacts of climate change.
