It is Central Asia's second largest lake and home to more than three million people, but Kazakhstan's Lake Balkash is under threat. The desert-locked sea is shrinking due to over-irrigation, caused in part by industrial neighbours such as China.
Many are concerned it could suffer the same fate as the Aral Sea, and eventually disappear.
Al Jazeera's Robin Forestier-Walker travelled with a team of scientists to Lake Balkhash - to find out why history could be about to repeat itself.