The reason? Well, in the late '60s, Soviet Russia embarked on a massive water project. They got the two rivers that fed the Aral to be directed towards the Kyzylkum Desert. They wanted the desertland to be irrigated and become fit for cotton farming, and the rivers were necessary for that. Sure, they got fertile lands, but at the cost of losing the fishing industry and communities around the Aral. Without the inflow, the salt in the lake made it evaporate faster than it could be filled up and by 2009, what water remained was full of pesticides and dust. The dust from the bared lakebed blew into storms and became a public health hazard. The highly saline dust formed a cover on the arable fields, and denuded the soil. Croplands had to be cleaned with river water in increasingly greater quantities.