The river basins under this Organisation are entire Cauvery Basin, the basins South of Krishna River and are as follows:

a. Cauvery Basin
b. West flowing rivers South of Tapi
c. Pennar Basin
d. East flowing rivers between Pennar and Cauvery
e. East flowing rivers South of Cauvery
f. Tungabhadra sub basin in Krishna Basin

Cauvery Basin

Cauvery basin extends over an area of 87900 sq. km. which is nearly 2.7% of the total geographical aree the country. It is bounded on the west by the Western Ghats, on the east and south by the eastern Ghats and the north by the ridges separating it from the Tungabhadra and Pennar basins. The basin lies in the States Tamil Nadu, Karnataka and Kerala. The State-wise distribution of drainage area is given below:

State
Drainage area (sq. km.)

Tamil Nadu
48730

Karnataka
36240

Kerala
2930

Total
87900

Physiography

Physiographically, the basin can be divided into three parts—the Western Ghats, the Plateau of Mysc and the Delta. The delta area is the most fertile tract in the basin. The principal soil types found in the basin are black soils, red soils, laterites, alluvial soils, forest soils and mixed soils. Red soils occupy large areas in t basin. Alluvial soils are found in the delta areas. The culturable area of the basin is about 5.8 M.ha which about 3% of the culturable area of the country.

River System

Cauvery river rises at Talakaveri on the Brahmagiri range in the Western Ghats in Karnataka at elevation of about 1341 m and flows for about 800 km before its outfall into the Bay of Bengal. The imports tributaries joining the Cauvery are the Harangi, the'Hemavati, the Kabini, the Suvarnavathi and t Bhavani. Click for basin map showing the river system and other features.

Hydropower Development

Recent hydropower potential survey in the basin has identified 30 hydropower projects with a total potential of 1359 MW at 60% load factor

PENNAR BASIN

Physiography

Pennar basin extends over an area of 55213 sq. km. which is nearly 1.7% of the total geographical area of the country. It is bounded on the north by the Erramala range, on the east by the Nallamala and Velikonda ranges of the Eastern Ghats, on the south by the Nandidurg hills and on the west by the narrow ridge separating it from the Vedavati valley of the Krishna basin. The basin lies in the States of Andhra Pradesh and Karnataka. The State-wise distribution of drainage area is given below:

State
Drainage area (sq. km.)

Andhra Pradesh
48276

Karnataka
6937

Total
55213

The important soil types found in the basin are red soils, black soil, sandy soil and mixed soil. The culturable area of the basin is about 3.54 M.ha which is about 1.8% of the total culturable area of the country.

River System

Pennar river rises from the Chenna Kesava hills of the Nandi ranges of Karnataka and flows for about 597 km before outfalling into Bay of Bengal. The principal tributaries of the river are the Jayamangal, the Kunderu, the Sagileru, the Chitravati, the Papagni and the Cheyyeru.

Hydropower Development

The basin does not have scope for hydropower development.