Hyderabad: Two more gates of the Osman Sagar were opened by the water board authorities here today on account of heavy rains (due to cyclone Gulab) leading to excess inflows into the lake. In total, four out of 15 gates of the Osman Sagar have been opened as of now, while one out of Himayat Sagar’s 17 gates remains open.
On Monday, the city and Telangana continued to receive heavy showers all day, with areas like Jubilee Hills receiving over 50 millimetres of rains. Due to the rainfall, the Hyderabad Metropolitan Water Supply and Sewerage Board (HMWSSB) had to open two more gates of the Osman Sagar, as the historic lake is getting flooded lake.
The reservoir, which is one of the city’s drinking water sources, has already reached full water level due to heavy rains, said the HMWSSB in a press release. (read more about todays rain here)
“From 23rd of this month two gates were raised. On Monday (today) at 2 p.m. another two gates were raised. With this, all the four gates are now being raised and 480 cusecs of water are being released into the Musi River,” stated the HMWSSB in its release. The water board’s managing director Dana Kishore advised officials of various departments to be vigilant about the catchment areas of the Musi River, as many low-lying areas on its banks may get flooded if mor gates are lifted.
As of now, the water level in Osman Sagar has nearly reached 100% capacity, as copious rains took its water level to 1789.90 feet, as against its full capacity of 1790 feet or 3.9 thousand million cubic feet (TMC) . Similarly, the Himayat Sagar is nearly full as well. Water in the lake is currently at 1763.30 feet as against its full tank capacity of 1763.50 feet (or 2.968 TMC).
Both lakes have a total installed capacity of 45 million gallon per day (MGD). However, due to lack of rains earlier and less dependence on it due to other drinking water projects coming from the Krishna and Godavari rivers, the Osman and Himayat Sagar lakes have been together supplying only about 15 MGD at best from the past few years.
Both Osman Sagar and Himayat Sagar were built to stop excess water from overflowing into the Musi River, after the 1908 devastating Musi river floods in Hyderabad which killed thousands of people. The 1908 floods took place during the time of Mahboob Ali Pasha, the Sixth Nizam of Hyderabad.
It led to him commissioning the services of M. Visweswaraya, the legendary Indian engineer, who suggested that two dams be built keep the Musi River’s water outside the city
While Mahbub Ali Pasha died in 1911, his son and the last Nizam, Osman Ali Khan, sought to develop Hyderabad and make it flood-proof. He got both the lakes constructed under the aegis of the City Improvement Board, which was set-up in 1912. Both lakes were then developed over the next two decades. While Osman Sagar was commissioned in 1913, the Himayat Sagar was commissioned in the early 1920s.