Limnology
The catchment area of the lake was found to be 3750ha and this area includes the residential areas of Yeshwanthpur, Mathikere, Rajmahal Vilas Extension, Bharat Electronics Limited and Hindustan Machine Tools Limited colonies. In 1974 the lake area was 77.95 ha and in 1998 it was 57.75 ha. Based on the rainfall of the region, the annual catchment was estimated at 15.2 million cubic metres with 3.04 million cubic metres during the Northeast Monsoon, 10.12 million cubic metres during the Southwest Monsoon and 3.28 million cubic metres in the dry season. The storage capacity of the lake was estimated in 2000 to be 2.38 million cubic metres with desilting raising it to 4.07 million cubic metres. Sewage inflow into the lake has altered the chemistry and biology of the lake. Most measured physico-chemical properties of the waters of the lake exceed the acceptable standards for sewage effluent discharge set by the Indian Standards Institute (Indian Standards: 2490, 1982).
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