Building better defenses against rising floods and storms

A woman looks out from her house at a flood affected area in Nepal

In the last few weeks, Hurricane Harvey hammered the Texas coast in the United States with a confirmed death toll of more than 60 so far, and massive flooding in India, Bangladesh, and Nepal has taken more than 1,200 lives. These are the most recent reminders of the rising fury of floods and storms. Emergency relief and recovery is unquestionably the immediate priority. But as climate change intensifies these hydro-meteorological events, the only lasting response is to step up risk management, which includes mitigation and prevention, prediction, and early warning.


It’s vital to strengthen capabilities for weather services that provide early warning and facilitate timely evacuation of those in the path of hurricanes. An example is the Japan Meteorological Agency, which recently updated its evaluation alert system to map the intensity of hazards and people’s special needs in these circumstances. What’s clear is that early evacuations pay off: Warnings and alerts via news networks, text messages, satellite phones, and loudspeakers went out four days before Cyclone Phailin struck in 2013, leading to the exodus of more than a million people. The population of Tulang Diyot—a small Philippine island off the main island of Cebu—was saved from the wrath of Typhoon Haiyan, the mother of all storms, because evacuations were enforced. 

Countries under storm threat must also prioritize accessible infrastructure for safe and uninterrupted water, sanitation, and electricity for health facilities. From Asia to Latin America, breaks in these lifelines are major causes of desperation and response failures that often follow natural hazards. Damaged roads and fallen bridges limit people’s movement to safer areas, in addition to shackling the delivery of life-saving medicines and hospital supplies. Disaster-proofing hospitals, as a preventive measure, adds less than a 10th to the cost of new hospitals, while rebuilding a destroyed hospital virtually doubles its initial cost.

Governments and aid organizations also need to be ready with lifesaving supplies. Emergency response and disaster relief need top attention, including getting aid to remote areas in time. Readiness also involves care in zoning regulations and building codes to protect businesses, homes, and neighborhoods. Both are key to avoiding the disruption of supply chains and information networks that we have seen during the massive floods in Sri Lanka, Chennai (India), and Thailand in the past decade. With higher and more varying sea levels and temperatures, structures need to be located further from coastlines than what was previously the norm.

The connection between more carbon in the air, higher sea level temperatures, higher precipitation, and rainfall is unmistakable to anyone except the extreme climate deniers.

Safe houses, breakwaters, and evacuation routes in the event of floods and storms will be increasingly important. Indonesia is one of the most disaster-prone countries in the world, regularly experiencing earthquakes, tsunamis, landslides, volcanic eruptions, flooding, and drought. In 2004, storms and floods from one of the deadliest tsunamis in history killed some 230,000 people in 14 countries around the Indian Ocean—nearly 170,000 of them in Indonesia. The subsequent preparedness efforts have offered positive lessons, including the construction of evacuation buildings, using existing roads and pathways, in Banda Aceh and other threatened cities.

Scientists are rightly careful not to link a single event to climate change, but the connection between more carbon in the air, higher sea level temperatures, higher precipitation, and rainfall is unmistakable to anyone except the extreme climate deniers. Cutting back on carbon dioxide will require technological breakthroughs in renewable energy driven by businesses and scientists, as well as public policy and regulations on emitting life-threatening carbon. The Paris climate accord, albeit modest in scope, is an essential step forward.

With the increased frequency of intense floods and storms, providing adequate financing for disaster management will be more and more important. Governments and external financiers need to facilitate affordable credit for reinforcing structures and homesteads and relocating people out of harm’s way, especially the poor and vulnerable. Investments in education, information sharing, and capacity development have also paid off in dealing with these calamities. Just as governments try to cushion financial shocks, so must they carry out stress tests of a state, country, or a region’s resilience to, for example, the occurrence of more than one once-in-a-100-year catastrophe in close succession.

The common refrain heard during the South Asian floods or Hurricane Harvey in the U.S. is that no one had seen or expected flooding on such a scale. Tragically, seeing a year’s rainfall in a day and a dwindling of the time span of “once-in-a-100-year” episodes is the new norm. We better wake up to this reality, get used to it, and take preventive action urgently.