Citing heavy rains that flooded thousands of homes in Quebec earlier this spring, as well as inundations in Sri Lanka and Colombia, the head of the Asian Development Bank’s independent evaluation office is urging national governments to direct at least 1% to 2% of their budgets to preventing increasingly extreme weather events from becoming human disasters.

Writing for the Brookings Institution’s blog, Vinod Thomas presents evidence that extreme floods and storms have occurred more often since about 1975. Both are influenced by the amount of heat and water in the atmosphere—factors that  intensify as the atmosphere warms. By contrast, disasters caused by geophysical events (earthquakes, tsunamis) have remained stable in number.

Growing populations in high-risk zones along coast lines and in river valleys contribute to the rising human consequences from such storms, Thomas concedes, but a “neglected” aspect is that increasingly extreme precipitation is overtaking water management infrastructure designed for decades past.

“In Sri Lanka’s latest floods, some places experienced more rain in a day than the usual for a year,” he observes. “Earlier this year in Colombia, heavy rains overnight caused rivers to burst their banks, taking over 200 lives.”

Mismanagement produces its own consequences. “Thailand’s 2011 floods—which submerged economic heartlands and caused losses amounting to 13% of GDP—were aggravated by the misjudged release of water from dams,” Thomas notes. “During the 2013 floods in Uttarakhand, India, the debris from dam construction upstream blocked rivers, augmenting the overflow.”

Thomas recommends an early focus on key social infrastructure points. Authorities should concentrate on “making hospitals, emergency shelters, and other vital installations more disaster resistant, and ensuring functioning lifelines—notably potable water, first aid, and power supplies—during disasters,” he writes. “This is essential, as floods can disrupt supply chains and information networks.”

With a continuing escalation of violent weather baked into the warming climate system for at least another several decades, the ADB evaluator notes, “disaster prevention must become a bigger priority to protect human and physical capital, and probably needs to be 1–2% of national budgets.”