One of the tributaries of the Cauvery River is the Shimsha River that flows in southern part of India. The river originates in the southern part of the Devarayanadurga hill at an average elevation of 914 metres, which is located in the Tumkur district of Karnataka. The total length of the river is two hundred and twenty one kilometers and has a catchment area of about 8,469 square kilometers. Maddur is a major city that lies on the bank of the Shimsha River. It reaches the border of Chamarajanagar district where it merges with the Cauvery River. The meeting of the Shimsha River with Cauvery occurs near the Shivanasamudra falls. Several small streams like Veeravaishnavi, Kanihalla, Chickkhole, Hebbahalla, Mullahalla and Kanva join the Shimsha River during it course. A beautiful sprawling dam is built across the Shimsha River in Igglur. At Shimshapura where the Shimsa River forms a waterfall there is the Shimsha Hydro electric Project. Shimsha has its waterfall at Shimshapura in Malavalli Taluk. This is also the location of the Shimsha Hydro Electric Project which has an installed capacity of 17,200 kilowatts. It was the first ever hydro electric project in Asia. Kolar Gold Fields was supplied with the electricity generated in the year 1902. Three years later Bangalore got electricity. The foundation stone for this project was laid by Krishnaraja Wodeyar IV, the king of Mysore in December 1937. The sand found on the river bed of the Shimsha river is mined and used for construction activities, sometimes illegally. Due to the environmental issues that can be caused by sand mining, this activity is currently banned.
Markonahalli Dam is a dam built across the river Shimsha in the Kunigal Taluk of Tumkur district. It was built by Krishnaraja Wodeyar IV, the king of Mysore under the guidance of his Diwan, Sir M Visweswaraiah. was built to irrigate 6070 hectares of land and has a masonry structure of 139 m and a pair of earth dams extending to 1470 metres on either side. The reservoir has a catchment area of 4103 km² and can hold a volume of 68 million m³ of water at a full reservoir level of 731.57 m above the mean sea level.27 species of fish, including 13 species of commercial fishes have been recorded in the reservoir with Puntius being the dominant species of fish found here. Cirrhinus reba and Labeo calbasu and other transplanted carps are also found here. However, the maintenance of the dam has been poor. In the year 2000, a part of the dam had to be demolished to prevent floods and save 25 villages.Water started overflowing the dam and only 1 crest gate could be opened. Nearly 150 feet of the dam was demolished in order to allow excess water to flow out.
The erstwhile Mysore State had the enviable and glorious position of establishing the first major hydro-electric generating station at Shivasamudram as early as 1902 for commercial operation. The art at that time was still in its infancy, even in the advanced countries. The longest transmission line, at the highest voltage in the world, was constructed to meet the power needs of mining operations at Kolar Gold Fields. The generating capacity of the Shivasamudram Power House gradually increased to 42 MW in stages. To meet the increasing demand for power, the Shimsha Generating Station, with an installed capacity of 17.2 M.W, was commissioned in the year 1938. The power demand was ever on the increase, for industries and rural electrification, and additions to generating became imperative. The 1st stage of 48 MW and 2nd stage of 72 MW of the Mahatma Gandhi Hydro-Electric Station were commissioned during 1948 and 1952, respectively.
In 2004 it completed 100 years of existance. Report in the Hindu:
It is a matter of pride that the princely State of Mysore was the first in Asia to harness its own electricity by setting up the continent's first hydel power station at the foot of the Shivanasamudra Falls near Kollegal in the present Chamarajanagar district. The authorities are now celebrating 100 years of the power station. The Shivanasamudra Hydro-Electric Power Project supplied electricity to Kolar Gold Fields in 1902 and in 1905 to Bangalore, which became the first Indian city to have power supply. The project was taken up in 1900 when K. Sheshadri Iyer was the Dewan after Mysore State decided in 1899 to utilise its natural water falls for producing electricity. The site of setting up the power station was a point on the Cauvery east of Mysore city and south of Bangalore where the river divides into two forming the island of Shivanasamudram. The work on the power station was completed by 1902 and on June 30 of that year, power was transmitted for the first time to Kolar Gold Fields. In December 1937, teMaharaja of Mysore, Krishnaraja Wodeyar IV, laid the foundation stone for the Shimsha Hydro Electric Project at Shimshapura. This was to augment power-producing capacity. Shimshapura had an installed capacity of 17,200 kilowatts. Now, the Shivanasamudra Falls have regained their beauty with the monsoon active in the catchment area.