Bearing six-liter bottles of water on their shoulders, members of Colombia's Indigenous Yagua community tramp along the dried-up riverbed of a branch of the mighty Amazon. In the Three Frontiers region, where Colombia borders Brazil and Peru, the flow in some spots of the world's biggest river by volume has shrunk by 90 percent, leaving a desert of brown sand etched with ripples. "In a few years, the river will dry up completely, and life will be even harder for us. We don't want to face that again," says Maria Soria, an Indigenous woman. The drought coincides with the worst Amazon fires in nearly 20 years, according to the European observatory Copernicus. IMAGES AND SOUNDBITES