Marconahalli Dam is a major dam in the Indian state of Karnataka. Here you can see the “water self releasing mechanism” (also called auto-siphoning mechanism). This mechanism was the first in Asia, conceptualized by Dr Sir M Vishveshwaraya. This mechanism is shown by the caretaker only at the rate of Rs.10 or so per person.

Location

Marconahalli Dam, also called ‘Marconahalli’, is located in Kunigal taluk of the Tumkur district in Karnataka. The dam is built across Shimsa River which is one of the tributaries of Kaveri River, one of the major rivers of southern India. Shimsha River originates in the southern part of Devarayanadurga Hill in Tumkur district and flows for about 221 km before it joins Kaveri River.

Construction

This dam was constructed by the king of Mysore, Krishnaraja Wodeyar IV, under the guidance of his Diwan Sir M Visweswaraiah. The latter designed its unique automatic siphon system. The purpose of the dam was to irrigate 6070 hectares of land. The length of the dam is 1812 meters and its height is 22.25 meters. This dam has a masonry structure of 139 meters and a pair of earth dams of length 1470 meters on both sides. The catchment area of the dam is 4103 square kilometers. The capacity of the dam is 68 million cubic meters of water at a full reservoir level of 731.57 meters above the sea level. The spillway is 183m long. 

Other Salient Features

The left bank canal is 28.8 km in length and has a capacity of 7 cumecs and irrigates 4000 ha of land. The right bank canal is 12.8 m long with a capacity of 1.13 cumecs and irrigates 560 ha of land. The crop pattern grown in this area is of kharif type.

Due to poor maintenance of the dam, a part of it had to be demolished in the year 2000 to prevent floods and hence save twenty five villages. Only a single crest gate could be opened when water started to overflow. As a result, around 150 feet of the dam was demolished to give way to the excess water.

Aquatic Life in the Reservoir

Nearly 27 species of fish have been found in the reservoir, out of which 13 species are of commercial type. Puntius is the main species of fish found in the reservoir. Cirrhinus reba, Labeo calbasu and other transplanted carps have also been recorded in the reservoir.

Nearby Tourist Attractions

Some of the popular attractions in Tumkur are:

• Siddaganga (Kyatsandra) Mutt
• Yediyur
• Siddara Betta
• Pavagada Fort
• Lakshmi Kantha Swami Temple
• Barachukki and Gaganachukki Falls, Mandya, Karnataka
• Krishnaraja Sagar (KRS) Dam, Mandya
• Bheemeshwari Wildlife Sanctuary, Mandya

How to Reach Tumkur

By Road

The city lies on National Highway No. 4 and hence there are regular buses from Tumkur to different parts of Karnataka and other neighbouring states. Tumkur is also close to Bangalore (74 km), Shimoga (207 km) and Belur (156km).

By Rail

Tumkur has good railway network. Tumkur is situated on the broad gauge train route from Bangalore to Shimoga and Hubli via Kadur. Tumkur is at a distance of 70 kms from Bangalore.

By Air

The nearest airport is at Bangalore at a distance of 74 km.