The Kok-Aral Dam was completed in 2005 to control the water level of the North Aral Sea. This dam has prevented further decline of the North Aral Sea, and by 2011 it helped restore the water salinity level to the that of the 1960s (8 grams per liter).
A dam can be seen as early as the 1998 image. It’s the straight angled lines on the southernmost part of the North Aral. This earthen dike was built in 1992 and later replaced by a concrete dam in 2005. At times, water from the North Aral is allowed to flow southward into the South Aral through the dam in the Berg Strait.