Himayat Sagar is an artificial lake about 20 kilometres (12 mi) from Hyderabad in Telangana, India. It lies parallel to a larger artificial lake Osman Sagar. The storage capacity of the reservoir is 2.9 tmc ft.
The construction of reservoirs on the Esi, a tributary of the Musi River, was completed in 1927, with the intention of providing drinking water source for Hyderabad and protecting the city from floods, which Hyderabad suffered in 1908. It was built during the reign of the last Nizam of Hyderabad, Nizam VII and is named after his youngest son Himayat Ali Khan.
The Himayat Sagar and Osman Sagar reservoirs provided continuous water supply to the twin cities of Hyderabad and Secunderabad until recently. Due to population growth, they are not sufficient to meet the cities' water supply demand.
The engineer at the time of construction was late Khaja Mohinuddin, son of Mohammed Hussein, Madri.