The dam was created on 18 February 1911, when the 7.4-Ms Sarez earthquake caused a massive landslide that blocked the flow of the river.

[1] The dam is formed of approximately 2 cubic kilometres (0.48 cu mi) of rock dislodged from the steeply sloped river valley of the Murghab, which cuts from east to west through the high and rough Pamir Mountains.

Water does not flow over the top of the dam, which would quickly cause it to erode away; instead, water seeps out of the base of the dam at a rate which approximately matches the rate of inflow, maintaining the lake at a relatively constant level.

Geologists are concerned that the Usoi Dam may become unstable during future large-magnitude earthquakes, which are relatively common in the seismically active Pamirs, and might collapse due to liquefaction or subsequent landslides during such an event.

This would focus and maintain any flood's destructive power as it swept through the valley of the Murghob District.