4. draInage (2022)

Drainage-Mysore district is endowed with a number of perennial and non-perennial rivers. The Cauvery, which is the major river system of the district, traverses the Mysore plateau from northwest to east along with its tributaries, Kabini, Suvarnavathi, Laxmanathirtha and others. The Cauvery rises at Talacauvery in Kodagu district and flows along the boundary of Periyapatna taluk, enters into the district through K R Nagar taluk. It further moves into T. Narasipur and Kollegal before reaching Tamil Nadu. The total catchment area of the river is the second largest in the State and it covers nearly 18 per cent of the land area of the State. It is the only river which has been harnessed for irrigation from ancient times and it is estimated that as much as 95 per cent of its surface flow is put to use before it enters into the Bay of Bengal. The drainage pattern is sub-dendritic to dendritic type in nature.

Aquifer systems encountered in the area The study of aquifer geometry and parameters have been attempted by Central Ground Water Board, South western Region, Bangalore, under its ground water exploration programme through drilling exploratory bore wells at selected places. Ground water occurs under phreatic conditions in the weathered rocks, top-soils and in river alluvium. Occurrence and movement of ground water is controlled by degree of weathering and fracturing in the weathered zone. These aquifers are developed by dug wells, dugcum-bore wells and shallow tube wells. The depth of dug wells in the district range from 5.28 to 17.59 m bgl. Cross sectional area of dug wells vary in the range of 5.39 to 115.31 m2.