From Texas floods to Himalayan glacier collapse, cities built for a climate that no longer exists are discovering that real resilience means connecting technology, nature, and people, not just adding more sensors.
Before dawn on July 4, 2025, the Guadalupe River at Kerrville rose from about 3 feet to 30 feet in just 45 minutes, turning part of the Texas Hill Country into a disaster zone.
In August 2026, a glacier collapse near the Nepal-Tibet border triggered catastrophic flooding that damaged settlements, roads and hydropower infrastructure.
Toronto and Southern Ontario have faced their own warning signs. In July 2024, intense rainfall flooded highways and subway stations, while a major power outage affected nearly 300,000 customers. Canada’s 2026 wildfire season has also forced evacuations.
These events are geographically different, but they expose a common vulnerability: many cities were built for a climate that no longer exists. Infrastructure designed around historical weather conditions is increasingly being tested by more intense rainfall, extreme heat, wildfires and other climate hazards.
We are also pushing against planetary limits.
The pressure is broader than climate change alone. The 2025 Planetary Health Check found that seven of the nine planetary boundaries have been crossed, including climate change, freshwater change, biosphere integrity, and ocean acidification. These pressures interact. Damage to ecosystems can weaken carbon sinks, while climate change can disrupt freshwater cycles.
In 2026, the United Nations University warned of “global water bankruptcy,” describing water systems so depleted or degraded that they may no longer easily return to historical conditions.
For cities, these pressures quickly become infrastructure challenges. Extreme rainfall overwhelms stormwater systems. Heat stresses buildings, electricity grids and public health. Drought and groundwater depletion threaten water security.
This is why mitigation and adaptation cannot be treated as separate agendas. Mitigation reduces the emissions driving future warming. Adaptation reduces impacts that are already occurring or can no longer be fully avoided.
Yet adaptation has a major financing problem. UNEP estimates that developing countries will need about US$310 billion to US$365 billion annually by 2035, while international public adaptation finance flows were only US$26 billion in 2023. Adaptation needs are now roughly 12 to 14 times current flows. Resilience plans cannot remain on paper when cities need drainage, cooling, early-warning and water systems now.
What does a climate-resilient city actually look like?
Smart buildings can reduce energy demand through efficient design, sensors and automated controls while improving thermal comfort and indoor air quality. At the neighbourhood scale, renewables, storage, microgrids and electric mobility can reduce emissions while strengthening resilience.
Internet of Things, or IoT, technologies can monitor rainfall, drainage, temperature and infrastructure performance. But a community is not “smart” simply because it has more sensors.
Some of the most powerful solutions work with natural systems. Low-impact development and sustainable stormwater management use rain gardens, bioswales, permeable pavements, green roofs, infiltration areas, and rainwater harvesting to retain, absorb, filter, or reuse rainfall close to where it falls. Blue-green infrastructure extends this through wetlands, urban forests, ponds, and waterways. The principle is simple: instead of designing cities only to move water away as quickly as possible, we can design them to absorb, store, filter, and reuse it.
Blue-green infrastructure shifts urban water management from moving rainfall away as fast as possible to absorbing, storing, filtering, and reusing it through rain gardens, bioswales, wetlands, green roofs, and urban forests built into the city fabric. Photo by Shox Art on Pexels.
Bangladesh offers a powerful community-level example. In salinity-affected coastal areas, women trained as “Pani Apas,” or water sisters, help households use and maintain rainwater-harvesting systems. The model does more than provide water tanks. It connects climate adaptation with safer water, women’s livelihoods, skills and community ownership. UNDP reports that related coastal initiatives provide year-round safe drinking water to nearly 140,000 people in parts of Khulna and Satkhira.
Costa Rica offers a different lesson from Latin America. Since 2015, nearly all of its electricity has come from renewable sources, with hydropower supplying around 70%, alongside wind and geothermal power. Yet prolonged dry periods increasingly challenge hydropower production. Costa Rica therefore illustrates why mitigation and adaptation must advance together. A clean electricity system still needs diversified renewables, resilient grids and water-aware planning.
The five Ps of sustainable development, People, Planet, Prosperity, Peace, and Partnership, provide a useful way to judge these solutions. People ask who is protected. Planet asks whether emissions, water, and ecosystems are considered together. Prosperity asks whether investment creates livelihoods and resilient infrastructure. Peace brings in fairness, trust and accountable institutions. Partnership recognizes that governments, communities, engineers, businesses and civil society organizations must work together.
The major gap today is often not the absence of solutions. It is our failure to connect them, finance them adequately, implement them equitably and maintain them over time.
Sensors can warn us that water is rising. Blue-green infrastructure can help absorb it. Rainwater harvesting can turn rainfall into a resource. Clean electricity can reduce emissions. But people still need the knowledge, resources and authority to operate these systems and shape the decisions behind them.
A truly smart and resilient city is not the one with the most connected devices. It is the one that connects technology, nature, infrastructure and people well enough to reduce risk before disaster occurs, protect the most vulnerable and recover more equitably when disruption cannot be avoided.
