The June heat waves that roiled the U.S. put tremendous pressure on the electric grid as air conditioning demand soared, resulting in rolling blackouts and power outages. Heavy rains in Midwestern states caused severe flooding that washed out a bridge and almost destroyed a Minnesota dam. Earlier in the month, rising temperatures caused the collapse of a major road between Idaho and Wyoming when runoff from melting mountain snowpacks triggered a landslide. And over 100,000 Houston-area residents are still without power, in dangerous heat conditions, a week after Hurricane Beryl touched down in Texas.
Climate change is making weather harder to predict, and creating new risks in places that never faced them before. And as hurricanes, floods, extreme heat and wildfires intensify, most infrastructure will need to be retrofitted or designed and built anew for future climate resilience.
Climate-resilient infrastructure is infrastructure that is planned, designed, built and operated with changing climate impacts in mind. Resilient infrastructure must not only withstand climate impacts, but also be able to recover quickly after disruptions. As an associate director at ARUP, a global sustainable development company, put it: “You need to prepare to be surprised.”
How climate change impacts infrastructure
Worsening impacts from climate change are taking a toll on infrastructure and communities in many ways.
Heavy precipitation and floods
As temperatures rise, heavy precipitation events are expected to become more frequent and intense. Downpours, storms and sea-level rise are already resulting in more coastal flooding and erosion. Intense storms and floods damage infrastructure such as homes, bridges, roads, buildings and the energy system. They also disrupt operations at airports, ports and power plants. Storms can cause rivers to overflow and flood riverine communities. According to FEMA, the areas of the U.S. at risk of flooding will increase 45% by 2100, and annual damages from flooding are predicted to increase by 30%.
A case in point: The Fourth Regional Plan, a development plan for the New York tri-state area, asserts that nearly 60% of the power-generating capacity (in other words, power plants), 21% of public housing units, 40% of wastewater treatment plants, 115 rail stations, and many miles of subway and commuter rail routes in the New York tri-state area will be at risk of flooding by 2050.
Heat
In the U.S., Arizona, California, Oregon, Nevada, North Carolina and Maryland have all recently broken temperature records. Extreme heat exacerbates the urban heat island effect, which makes cities hotter than surrounding areas because pavement, buildings and other hard surfaces absorb and retain heat. Higher daytime and nighttime temperatures and the resulting air pollution can cause heat-related deaths and illnesses and exacerbate existing illnesses. The heat island effect also creates more demand for air conditioning and electricity, which can produce brownouts or blackouts. More than half of the world’s population currently lives in cities and because the urban population is expected to double by 2050, the heat island effect will likely worsen, especially in low-income and marginal communities that have fewer trees and less vegetation.
Outside of cities, higher temperatures melt roads and buckle railroad tracks. In the northern and southern hemispheres, permafrost is thawing, which also results in damaged roads and crumbling building foundations.
Drought
Less precipitation and higher temperatures are increasing the risk of drought, which stresses water supplies as more water evaporates from reservoirs and decreases the water supply. Lower water levels may affect transport on inland waterways. Drought can also deplete aquifers that drinking water and irrigation depend on. And if there is less water available, the output of hydropower and nuclear power plants may be compromised.
Wildfires
Higher temperatures and increasing extended drought doubled the number of wildfires in the western U.S. between 1984 and 2015. Warmer and drier conditions are also creating longer wildfire seasons as more and more homes are being built in wildfire-prone areas, the zone between unoccupied land and urban development called the wildland-urban interface (WUI). Wildfires damage homes and buildings, as well as ecosystems and habitats. An added consequence is that water lines, particularly in the western U.S., are often made of plastic, which can withstand earthquakes, but when these water lines heat up, they can leach volatile organic compounds into the water system.
The current state of infrastructure
Every year from 1998 to 2022, the U.S. received a grade of D or D+ on its infrastructure report card from the American Society of Civil Engineers (ASCE). In 2023, it rose to C-, thanks to improvements funded by the Bipartisan Infrastructure Law of 2021; because of the law, the grade is expected to improve further this year.
Due to our historic underinvestment in highways, bridges, rail, transit, drinking water, stormwater, wastewater, electricity, airports, seaports and inland waterways, the ASCE estimates that $15.2 trillion by 2043 will be needed for improvements.
Globally, the OECD projects that $6.3 trillion each year through 2030 will be needed for infrastructure as countries develop. Most of this will be spent in low- and middle-income countries, providing residents with access to energy, clean water, transportation and communication networks as urban areas expand. Developed countries will need to spend money to retrofit, replace or upgrade their current infrastructure.
In the U.S., the 2021 Bipartisan Infrastructure Law and President Biden’s Inflation Reduction Act apportions over $50 billion for climate-resilient infrastructure in every community.
Thaddeus Pawlowski, director of Columbia University’s Center for Resilient Cities and Landscapes, said, “We haven’t spent that kind of money on infrastructure since before the Reagan administration, when trickle-down economics became the way we expected things to be accomplished as a society—which never worked out and left us with crumbling infrastructure. Now we have a chance to build infrastructure again. I just hope we do it the right way, and that means climate resilience on lots of levels.”
The National Climate Resilience Framework, which will guide the implementation of resilience strategies, says, “Under the president’s direction, every federal department and agency is focused on strengthening the nation’s climate resilience, including by tightening flood risk standards, strengthening building codes, scaling technology solutions, protecting and restoring our lands and waters, and integrating nature-based solutions.”
According to the ASCE, trillions of dollars are invested by the government and private sector each year on infrastructure that may not withstand the impacts of a changing climate. Infrastructure has always been designed to be resilient, but mainly to hazards we’ve experienced in the past. Moreover, the codes and standards that civil engineers use to design and build are based on the outdated assumption that the climate is fairly consistent.
ASCE, the University of Maryland and the National Oceanic and Atmospheric Administration (NOAA) are now partnering to use NOAA’s climate data to develop and update ASCE codes and standards with future risks in mind; these codes influence most building codes in the U.S. and abroad.
Infrastructure and environmental justice
Nowhere is there more of a need for climate-resilient infrastructure than in marginalized and underserved communities in the U.S. and around the world. Their infrastructure is usually poor because there has historically been less investment in repairs and improvements in these communities. Zoning laws have often allowed polluting industries into these areas. Moreover, because they lack political power, these communities are usually left out of decisions about infrastructure. Consequently, they are harder hit when extreme weather events occur.
Hugo Sarmiento, assistant professor in the Urban Planning Program at Columbia Graduate School of Architecture, Planning and Preservation (GSAPP), said, “In New York City, for example, one of the largest concentrations of public housing is in the Far Rockaways in Queens. Hurricane Sandy impacted places like the Far Rockaways most heavily. So if you’re going to build housing in these low-lying flood plains and flood-risk areas, it is absolutely critical that there’s also investment in resilient infrastructure.” Sarmiento believes low-income communities not only need access to adequate housing, but also to mobility within the housing market that allows them to look for homes in areas that are less risky or less prone to flooding.
According to Pawlowski, we also need to think about the way infrastructure of the past has contributed to our global climate crisis by locking us into fossil-fuel dependent lifestyles, while exacerbating inequality. “Infrastructure has been weaponized in the past,” he said. “For example, the interstate highway system divided our communities to create permanent housing segregation, causing a lot of the fracturing of American society. But without raising the specter of green gentrification, there is a way to have localized wealth creation through investment and infrastructure. It’s about community wealth building, and also about economic opportunity in the form of jobs and infrastructure.”
It’s important for community-based organizations to be able to develop their own vision for how the community should be adapted to the changing environment. “They know best what their needs are,” said Sarmiento. “They know best how they experience the climate crisis, and providing support for them to develop their own plans and visions for how to do that makes the most sense.” Moreover, because “infrastructure needs to be loved” to get support, Pawlowski said, “it’s important to create more decentralized infrastructure so that individual communities or community groups can really take stewardship.”
The elements of climate-resilient infrastructure
The strategies for resilient infrastructure vary depending on where it is, as different parts of the world face different climate risks. But certain principles remain the same.
Planning and design
Planning should start with the best available science to research potential climate conditions over a project’s lifetime and how they might affect people and the infrastructure. Total resilience is not possible because many uncertainties remain about how the climate will change. But given what is known and projected, a project should be sited where climate risks are lower; for example, avoiding building in a flood plain or in the wildlife-urban interface. Dealing with future uncertainty might entail designing for the short term and making changes in stages as climate conditions change.
Designing flexibility into a project is another way to accommodate future uncertainty. While most architecture is static, flexible architecture is mobile, moveable and multifunctional. For example, power lines are usually built with a fixed design that provides for a specific number of gigawatts. Incorporating flexibility into the system could include adding more land for extra concrete foundations on which to build new transmission components in the future if more energy is needed. Generators would be designed to accommodate new transmission lines as well. One analysis found that this strategy could add 70% more value than the typical fixed design.
Designing a building to be adaptable also makes it more resilient. Over 75% of waste from construction is not reused or recycled and likely ends up in landfills. Adaptability keeps waste materials out of the landfill and preserves resources. Adaptable architecture often features clear open spaces that can be used in multiple ways and easily changed in the future. Ample floor to floor heights make it easier for a building to add ventilation or switch from commercial to residential use. Non-load-bearing partitions can be easily moved. Strengthening a structural system allows for building future additions or solar or green roofs. Adaptability also means that zoning laws and building codes need to continually evolve in line with climate projections.
Systems should be designed to be redundant and self-sufficient, so that one system failure will not impact the whole building. For example, energy redundancy might include microgrids which can operate separately from the larger grid if necessary, or backup power or cogeneration, which produces electricity and captures and uses the waste heat. Separating the mechanical, electrical, plumbing, communications and other services ensures that they can be maintained or upgraded without interfering with other systems.
In areas where storms and flooding occur, planning should consider siting a building on higher ground or elevating it. The site should be graded so that excess water is directed to detention areas, and permeable surfaces with drainage used to lessen flood risk. If a building is in an area at risk of coastal flooding, it should be flood proofed and use waterproof materials; permanent or deployable flood barriers might be necessary. Critical building systems should be moved to higher floors.
To withstand storms, buildings can be oriented to best deal with high winds. Structural elements might need to be braced, and connections between foundations and the roof strengthened to keep roofs from blowing off. The shape of a building can also add to its resiliency. For example, a seaport building in Boston built by the construction company Skanska is oval shaped; this makes it less vulnerable to high winds and eliminates the need for extra structural elements for strength.
Planning for extreme heat and the urban heat island effect might entail orienting the building to lessen sun exposure or improve ventilation. It could require that a large amount of the site be shaded or planted with vegetation. Mechanical cooling—air conditioning—will be needed for occupied spaces, but if it isn’t possible, passive cooling strategies such as planning for cross ventilation, using exterior window shades, ceiling fans and triple-glazed windows should also be implemented.
In drought-prone areas, tanks or cisterns can collect water from rainfall for irrigation or toilet flushing. Homes built in wildfire-prone areas should clear flammable vegetation away from the building perimeter to hinder the spread of fire.
Materials
Designing climate-resilient infrastructure includes using durable and low-carbon materials. There are many new materials and strategies being developed, aimed at sustainably making buildings cooler or warmer and reducing carbon emissions. Here are a few examples.
Much of the world’s infrastructure is built with cement and concrete whose production is responsible for 9% of global CO2 emissions each year. As cities expand, its use is on the rise. Numerous companies are developing more sustainable concrete such as self-healing concrete that can seal its own cracks with chemicals, water and CO2 from the air. Japanese CO2-SUICOM is a concrete that sucks CO2 from the air. The Dutch company Respyre’s new cement is porous and retains water, and because it contains nutrients, moss will grow on its surface, which can help cool buildings. And AquiPor’s permeable concrete manages stormwater and recharges the groundwater.
Cool roofs—white, green or those using special tiles—reflect sunlight and reduce the temperatures of buildings and neighborhoods. Heat-resistant materials used on buildings can slow the transfer of heat from the outside to the interior. Cool pavements—light-colored concrete or those containing reflective particles—reduce the urban heat island effect.
Smart windows insulate buildings and can retain heat or cooling more efficiently. Some use low-emissivity glass, which contains microscopic metallic particles that reflect infrared radiation to deflect solar energy. Electrochromic glass windows change their tint in response to the light from outside, much like transition sunglasses. New hydroceramic surfaces are made with hydrogel, which can expand and absorb humidity to keep building interiors comfortable. And mineral paints reduce the amount of solar heat absorbed by the surface so it remains cooler.
In areas at risk of wildfires, buildings and homes should be built or retrofitted with fire-resistant materials and window frames. Metal siding, asphalt composition shingles and fiber cement are all examples of wildfire-resistant materials.
Nature-based solutions
Natural infrastructure includes solutions such as wetlands and mangroves, or nature-based solutions like green roofs. According to the Environmental and Energy Study Institute, natural solutions are often higher-quality, lower-cost and more resilient than gray infrastructure—gutters, drains, pipes, retention basins, which over time need to be maintained and repaired. They also provide co-benefits such as carbon storage, improved water and air quality, decreased erosion, increased biodiversity and recreational and tourism opportunities.
When coastal storms occur, gray infrastructure redirects the waves. Restored wetlands, mangroves, marshes, dunes and oyster reefs reduce wave energy and height and thus lessen erosion and flooding. In the northeast U.S., coastal wetlands have reduced flood damage by 16%. Restoring flood plains and wetlands and planting vegetation along river banks can help reduce flooding from rivers.
Living shorelines, composed of native vegetation and natural materials, create a barrier that can stabilize coastlines, reduce erosion and lessen the intensity of waves. One example is Living Breakwaters, a project designed by Kate Orff, architecture professor and director of the Urban Design program at Columbia GSAPP and professor of climate at Columbia Climate School. Along the coast of Staten Island, which was overwhelmed by Hurricane Sandy’s storm surge in 2012, stone and concrete barriers are being built and will be seeded with oyster larvae to eventually create an oyster reef. The breakwaters and oysters will slow and clean the water, reverse erosion and rebuild the subtidal and intertidal marine ecosystem where oyster reefs once thrived. “The natural systems are in various stages of decline,” said Orff. “In order to repair them, we have to think and design systemically to tie the pieces back together. These intact landscape systems protect and sustain us.”
The urban heat island effect is exacerbated when gray infrastructure absorbs heat and reduces the amount of moisture in the air. Trees, rain gardens and green walls cool the environment and reduce stormwater runoff. Areas that are shaded by tree cover can be 20 to 45°F cooler than sunny areas. In addition, because green infrastructure reduces the amount of water that enters sewers while recharging aquifers, less energy and money is spent treating wastewater and drinking water. Green roofs can insulate buildings against heat loss in winter and heat absorption in summer. One Canadian study found that a large green roof reduced daily air conditioning demand by more than 75%.
Early warning systems
Early warning systems are an essential part of climate resilient infrastructure because they help communities prepare for climate hazards, which can reduce infrastructure damage, and save lives and livelihoods. The UN has called for an Early Warnings for All initiative led by the World Meteorological Organization to make sure that every person on Earth has access to an early warning system by 2027. The system could incorporate AI to forecast and monitor events and provide disaster warnings to specific groups; remote sensing and satellite technology to develop predictions; cell broadcast and SMS to send messages to cell phones; the internet of things to provide real-time data and nature-based solutions to lessen climate impacts.
Examples of effective climate-resilient infrastructure
Netherlands: Room for the River
Almost a third of the Netherlands is located below sea level and about 60% of the country is vulnerable to flooding. The Room for the River initiative, begun in 2006, encompasses 34 projects along four rivers, including the Rhine, which floods every year. Instead of building higher dykes, the project moved dykes further from the river to broaden the flood plains, and flood plains were excavated to give the river room to expand. Riverbeds were deepened, and new side channels were created as flood bypasses. Davenport, Iowa has also made room for the Mississippi River. Instead of levees or flood walls, it has designed nine miles along the river with parks, bike trails, parking lots and even a stadium that are designed to be flooded.
Singapore: cooling program
Over the last 60 years, Singapore has warmed twice as fast as the global average. The city-state’s program to cool itself includes trees and plants on rooftops, in gardens, along streets and even on building walls. Besides providing shade, the greenery releases water vapor that cools the air and helps move hot air away from the ground. Many building roofs are painted with light colors to reflect sun radiation. New buildings are sited so that they do not face the sun directly and are built to allow for cross ventilation within. A large new development called Marina Bay features a park filled with trees, and homes cooled by chilled water that runs through a network of insulated pipes.
Badajoz, Spain: preparing for heat and drought
Temperatures in the region around Badajoz, Spain are projected to increase by approximately 4° C by 2100. To prepare for extreme heat and the expected water scarcity, nature-based solutions have been implemented at one pilot school. These include green roofs and facades, and other plants for shade, which will keep indoor temperatures cooler on hot days, reduce energy use and decrease rainwater runoff. An automatic ventilation system that closes and opens windows in the morning and night allows fresh air to circulate. A rainwater collecting system will be used to irrigate the school’s greenery. Permeable pavement allows water to infiltrate into the soil. The hope is to replicate this model and strategies at other schools.
California: wildfire resistance
In a state that faces devastating wildfires every year, Portola Valley, CA has amended the statewide building code, adding a home hardening ordinance that requires new homes built in risky areas to utilize the highest wildfire resistant construction materials. Development in the WUI is also limited. Vegetation is being reduced along evacuation routes, and residents are encouraged to create a defensible space—a buffer between a home and the grass, trees or wildlands around it— surrounding their homes. Emergency communication and evacuation planning are being enhanced as well.
What’s needed to advance climate-resilient infrastructure
Governments play a key role in building climate-resilient infrastructure. They can prohibit construction in risky areas, require better construction practices that take climate impacts into consideration and institute mandatory resilience standards. They can also reform insurance policies such as FEMA’s National Flood Insurance Program to reflect climate impacts.
Investing in climate-resilient infrastructure pays off. According to the World Bank, each $1 invested in climate resilience will generate a return on investment of $4, by avoiding the need to continually repair and rebuild. MIT research found that investments in climate-resilient construction pay for themselves within two years in avoided damage costs. Nevertheless, it is challenging to secure investment for resilience because the costs are incurred up front, while the benefits may take a long time to be felt. One water engineer said that investing in resilience can be “a tough thing to convince people to do because when you invest in resiliency, the payoff is that nothing happens.” Governments thus need to make the economic case for investing in climate resilience to potential investors. They can also encourage investment in climate resilience through tax incentives, grants and green bonds.
Is the U.S. making progress on climate resilient infrastructure?
“From a planning perspective, looking at what cities are doing in the United States and even in Latin America, we are still operating within the context of disaster recovery,” said Sarmiento. “Most cities are still in a reactive mode as opposed to [implementing] forward-looking proactive strategies. Those strategies, I think, are being developed and are being designed and exist in planning documents. But in practice, I don’t see a lot of that happening yet.”
Pawlowski is a bit more optimistic. “I think there are incremental steps happening,” he said. “Infrastructure is so risky to build. It costs a lot of money. There are a lot of political minefields. It’s just really hard to do. I feel like we’re in the very earliest stages where the pathways are just starting to be built. Hopefully once those pathways are created, they will keep getting replicated.”
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