(1860-1956)
GENERAL
The endemic famine region of Rayalseema, comprising the districts of Bellary, Anatapur, Kurnool and Cuddapah attracted the attension of the British Engineers as early as 1860. To relieve the intensity of famine in these districts , proposals were made in 1860 to utilize the waters of Tungabhadra through a storage reservoir and a system of canals to provide irrigation for the lands
AGREEMENT ON SHARING TUNGABHADRA WATERS
Sir Arthur Cotton originally conceived the Tungabhadra Project in the year 1860. The proposals were further modified and developed subsequently evolving it into a joint scheme with Hyderabad. Shri N. Paramseswaran Pillai accordingly revised the Scheme in 1933. Several agreements were concluded in the past for harvesting and imposing certain restrictions on utilizing the Tungabhadra waters. Protracted negotiations and investigations lasted for about eighty years. Govt. of Madras in 1940 ordered for the detailed investigation of the scheme. Based on the agreements concluded and examination of a number of alternatives by Sri L.Venkata Krishna Iyer, the then Superintending Engineer, Bellary and Mr F.M.Dowley, Chief Engineer, Irrigation, further detailed investigations of the project was done by Sri M,.S.Thirumale Iyengar on the Madras side in the year 1942. The Agreement between Madras and Hyderabad of June 1944 enabled the Madras and Hyderabad Governments finally to start the construction of the Tungabhadra project.
INAUGURATION
The Tungabhadra Project was formally inaugurated by laying foundation stone on 28th February, 1945 by “Prince of Berar” on the left side and by ” Sir Arthur Hope” Governor of Madras on right side. However, much headway could not be made up to January 1949. Difference of opinion in certain technical matters and settled political situation in Hyderabad were the reasons for the slow progress. The Madras and the Hyderabad engineers were sharply divided on,
| 1 | Nature of mortar to be used in the construction of the dam |
| 2 | Design of spillway |
| 3 | Design of over flow and non-overflow sections of the dam and |
| 4 | Contraction joints. |
These differences were referred to a Board of Engineers under the Chairmanship of Sri M.Visveswaraya, Statesman-cum-Engineer to whom the people of Mysore owe a lot for his foresight and ingenuity for having launched very many schemes during his tenure of Dewanship.
DAM CONSTRUCTION
Excavation in the riverbed was started in 1947 and masonry construction on the 15th April 1949. With help of a cofferdam constructed earlier, foundation excavation was continued during flood season also. The river bed portion was tackled during the summer of 1950 (1949-50). Masonry in the riverbed blocks was started in the year 1951. Thereafter there was vigorous progress in works. By October 1953 the structures were completed substantially enabling the storage of water in the reservoir upto +1613.00 ft. Acquisition of lands and villages and rehabilitation of persons displaced from the water spread area upto 1630ft contour were completed by September, 1953 in all respects. About 90 villages and 54,452 people were effected. The balance of the works namely the spillway, bridge road on the top of the dam, construction of utility tower, manufacture of crest grates for storing water upto 1633 level were completed in all respects by the end of June 1958. The cost of dam and appurtenant works was Rs. 16.96 crores. The water was led down into the canal on the 1st of July 1953 to derive partial benefits. Some important milestones in the construction of Dam are:
| Foundation excavation | Completed by June 1952 |
| Masonry | Completed by October 1953 |
| Drilling and Grouting | Completed by August 1955 |
| Crest Gates, embedded part | Completed by February 1955 |
| Spillway shutters | Completed by June 1955 |
| Operation bridges | Completed by February 1956 |
| Counterweight erection | Completed by January 195 |
| Hoists | Completed by January 1957 |
| Gate House | Completed by June 1957 |
| Utility Tower | Completed by June 1958 |
Power Canal of LLC System (Right side)
Power Canal works started in June 1954 and were completed by May 1957.
Right Bank Low Level Canal
The project submitted by Sri M.S.Tirumale Iyengar in 1942 for Low Level Canal was accepted by Govt. of Madras with certain modifications fixing sill level at RL 1550ft. The Low Level Canal excavation was completed by 1953 upto Mile 173. The balance portion of canal from Mile 173 to 203 that had to be excavated by the GOAP was completed by the end of March 1957.
Left Bank Main Canal:
As major portion of the construction of the dam was over by the middle of 1953, the reservoir circle was entrusted with the construction of canal works in 1956. In 1958 water was let out upto and inclusive of distributory 42 to serve an area of about 1.80 lakh acres.
Right Bank High Level Canal:
By 1952, when project sanctioned by both the Govt.’s for constituting Tungabhadra Reservoir and the canals reached advance and decisive stage of construction, the Govt. of Madras in GO 382 dated 30-1-1952 ordered investigation of the High Level Canal. On 15-11-1952 detailed estimates were got prepared upto Mile 79/2 covering the reach just before Chinna-Hagari and by 1954 the investigation of the remaining portion of canal from Mile 79/2 to Mile116/0 was completed and project report submitted to Govt. of India for approval. The proposals were further reviewed and a final project report to the Planning Commission costing Rs.21.90 crores for head discharge of 4000 cusecs for clearance. The CWC advised the participating states to execute the project in two stages. The 1st stage contemplated an unlined canal with a head discharge of 2300 cusecs and the 2nd stage a lined canal with 4000 cusecs head discharge.
The 1st stage scheme was inaugurated by the Governor of Andhra on the 2nd of October, 1956 under the presidency of the Chief Minister of Mysore. The 1st stage work was almost completed by June 1966 at a cost of Rs. 920 lakhs and canal commissioned by releasing water for Irrigation on 27th July, 1966. The 2nd stage works were approved by the Board in June 1967 for Rs.385 lakhs. The works were completed by June 1970 at an estimated cost of Rs.487 lakhs.
Hydro Electric Scheme
The Tungabhadra Hydro Electric Scheme was undertaken in the composite Mardas State in the post war period under the first five-year plan in the year 1950. The work on the project was taken up in the year 1951 but no appreciable progress was achieved till the end of the year 1953. During 1957 two units of 9 MW each at Dam Power House were installed and in 1958 two units of 9MW each were installed at Hampi Power House. Thus the first stage of the scheme was completed in 1958 and the second stage under this scheme was taken up in the year 1959. The plant erection was started in the Dam Power House in Nov.1962 and in the Hampi Power House in February `1963. Under stage II the units 3 and 4 of both, Dam Power House and Hampi Power House started functioning by June 1964.
Left Side Power House:
On left side the powerhouse is designed to accommodate 4 units of 9MW each. The stage I power generation commissioned during 1960-61.