1,643 Nepalese children escaped a mud tsunami that killed nearly 800 people and left 3,000 missing (13 dead and 546 missing on the Chinese side) at the Sino-Nepalese border. A school official in Nepal had the presence of mind to lead students to the mountain heights flanking the river valley on both sides. The images are striking: a gentle river along whose banks people had settled. A fundamental error that would be ruthlessly exposed by a glacier collapse. In the canyon, waves squeezed by the walls rose several dozen meters high, while in the wider valley, the torrent bed expanded by 300 meters. While footage was still capturing what happened far upstream, one could already wonder what on earth those houses and that town were doing kilometers downstream, directly in the path of this mud torrent and far below the cameraman's commanding view. In our land, spatial planning followed entirely different logic: building settlements on plateaus atop hills or mountains, while dedicating valleys to agriculture. A traditional and beneficial approach throughout Imerina before colonial administration decided to conquer the rice paddies and the Malagasy Republic perpetuated this double folly: leveling the Anjeva hills to fill the Betsimitatatra and float the 67-hectare polder district there. No glacier risks detaching from 5,000 meters altitude under our tropical sun, and neither the Ikopa nor the Mamba have the flow rates of Nepal's entrenched waterways, but when the river and its tributaries swell together from fahavaratra rains or cyclonic precipitation, they transform the Betsimitatatra into Mesopotamia. A flat sea where water has reclaimed its rights—its natural course. Floods nearly as devastating as the impressive catastrophe that struck that Himalayan valley. Natural disasters occur so that humanity may choose to learn—or not—from its mistakes. Nasolo-Valiavo Andriamihaja