Aral channel, and Danister Canal. Environmental degradation The lake supports thousands of fisherfolk, who depend on the freshwater fish in the lake. The lake since construction of the Main Nara Valley Drain in 1921 has undergone environmental degradation with inflow of sewage. Consequently, the water quality of the lake has been degraded. The diversion of water from the Indus and a diminished storm runoff from the Kirthar mountains have contributed to the reduction in fresh water supplies, resulting in the water becoming saline, and killing off fish. At the same time, saline drainage water from agricultural fields of Balochistan and surrounding areas flows into Lake Manchar. The lake was a stop-off on the Indus flyway for Siberian migratory birds, but the numbers have fallen from 25,000 birds counted in 1988 to 2,800 birds counted in 2002, because the lake no longer provides the birds' main food, the lake fish. In the place of the birds, the lake now hosts a saline water reed. The lake also provided large volumes of water for irrigation, but this has also been reduced and has resulted in a great reduction in the area irrigated by the lake. Right Bank Outfall Drain is being built to save the lake from contamination. Construction of the Nai Gaj Dam upstream from the lake will result in freshwater being discharged into the lake throughout the year, instead of seasonally, which should improve the lake's waters. Population Lake Manchar is populated by the Mohana tribe, who are sometimes referred to as the "Boat People." The lake supports thousands of fisherfolk, who depend on the freshwater fish in the lake. See also Environmental degradation Indus River List of lakes of Pakistan Kalankar lake References External links Lakes of Sindh Shrunken lakes