Lake Merzbacher (Kyrgyz: Мерцбахер көлү) is a moraine glacier lake located in east Kyrgyzstan between the north and south Engilchek Glaciers in the Tien Shan Mountains.

[2] The lake was named after a German explorer, Gottfried Merzbacher, who led an expedition in the area in 1903.

[1][3] An ice dam prevents the lake from draining through the majority of the year.

However, when a hole finally melts through the dam, the lake drains within three days.

[3] When this happens, the lake's discharge can be up to 1000 m3 a second which causes destruction of infrastructure and creates major flooding downstream.