Musi River (India)

Musi River or Musinuru is a tributary of the Krishna River in the Deccan Plateau flowing through Telangana state in India. Hyderabad stands on the banks of Musi river, which divides the historic old city and the new city. Himayat Sagar and Osman Sagar are dams built on it which used to act as source of water for Hyderabad. The river was known as Nerva during Qutub Shahi period.

The Musi river was the cause of frequent flood devastation of Hyderabad city until the early decades of the 20th century. On 28 September 1908, Hyderabad was flooded, which included 17 inches of rain in one day, killing around 15,000 people.[1]

The modern era of the development of the twin cities began soon after these floods in 1908. This necessitated planned, phased development.[2][3]

Abdallah Ahmed Bin Mahfooz submitted his report on 1 October 1909, with recommendations on preventing a recurrence of floods and improving civic amenities. However there are conflicting reports that Sir M. Visvesvaraya was engaged by the erstwhile Nizam to help design the drainage system and prevent floods. Nizam VII constituted a City Improve Trust in 1912. He built a flood control system on the river. A dam was built in 1920 across the river, ten miles (16  km) upstream from the city called Osman Sagar. In 1927 another reservoir was built on Esi (a tributary of Musi) and named Himayat Sagar. These lakes prevented the flooding of the River Musi and are major drinking water sources for Hyderabad city.[3][4]

Due to indiscriminate urbanization and lack of planning, the river has become a receptacle of untreated domestic and industrial waste dumping out of Hyderabad. It is estimated that nearly 350 MLD of polluted water and sewage originating from Hyderabad and Secunderabad flow into the river. Efforts to clean it have failed. The river water downstream of the cities remains highly polluted, considered a major disaster in Hyderabad.