Within the rugged Pamir Mountains of Tajikistan lies Lake Sarez, a very young lake basin that was created just over a century ago by a massive earthquake. In 1911, a 7.5-magnitude earthquake struck the Pamir Mountains, triggering a huge landslide that dammed the Murghob River that once drained the basin. This dam is now known as the Usoi Dam, and steady influx of water from rain and tributaries into the basin made Lake Sarez into what is today. More than 5.5 million people live downstream of the Usoi Dam along the Amu Darya river valley, which flows through four different countries: Tajikistan, Afghanistan, Turkmenistan, and Uzbekistan. The mountainous region surrounding Lake Sarez remains susceptible to earthquakes, which could easily destabilize the Usoi Dam. If the dam were to be damaged in any way, Lake Sarez would become a massive wall of water that could severely flood the downstream river valley. Researchers and government officials have proposed draining the lake as a preventive measure, including building a diversion tunnel that may also be used for hydroelectric power.