One of the world’s largest artificial lakes, Lake Nasser is named after the Egyptian President Gamal Abdul Nasser, who is largely responsible for the lake’s creation. President Nasser decided to build the Aswan High Dam across the Nile, forming a lake approximately 550 kilometers (340 miles) long.
Lake Sarez, deep in the Pamir mountains of Tajikistan, was created 90 years ago when a strong earthquake triggered a massive landslide that, in turn, became a huge dam along the Murghob River, now called the Usoi Dam. The resulting lake is perched above surrounding drainages at an elevation greater than 3000 meters. The lake is 61 kilometers long and as deep as 500 meters, and holds an estimated 17 cubic kilometers of water. The area experiences considerable seismic activity, and scientists fear that part of the right bank may slump into the lake, creating a huge wave that will top over and possibly breach the natural dam. Such a wave would create a catastrophic flood downstream along the Bartang, Panj and Amu Darya Rivers, perhaps reaching all the way to the Aral Sea.
Ongoing drought and diminished snowpack in the Rockies have combined with increasing demands downstream to cause the great reservoir to drop to historically low levels.
Heavy winter and spring snowfall provided much-needed meltwater, but the effects of long-term drought mean the lake is nowhere near its highs from the 1980s and 90s.