How much of its original water volume had the Aral Sea lost by the end of the 20th century?

By the end of the 20th century, the Aral Sea had lost three-fourths of its original water volume compared to its 1960 levels.1

This dramatic decline was primarily caused by the diversion of the Amu Darya and Syr Darya rivers for large-scale irrigation projects initiated during the era of the Soviet Union. As these primary water sources were redirected, the lake could no longer maintain its water balance against evaporation, leading to a significant reduction in both its surface area and volume. By the late 1980s, the sea had already lost more than half of its pre-1960 water volume, a process that continued to accelerate throughout the following decade.21