HYDERABAD: Billed as “the mother of all reservoirs” in Kaleshwaram Lift Irrigation Scheme, Mallannasagar, the largest artificial water body, is now ready to serve the people of the State and the country, after overcoming all odds and obstacles. Irrigation experts claim that Mallannasagar is the biggest artificial reservoir in the country, which will be filled entirely by lifting water from other sources and not with water received from its self-catchment area.
Chief Minister K Chandrasekhar Rao will inaugurate Mallannasagar on February 23 and dedicate it to the nation. It will provide irrigation to 11.29 lakh acres. “Mallannasagar is centrally located in Telangana and as mother reservoir of Kaleshwaram Project, it will cater to the needs of irrigation and drinking water requirements of Telangana people. With the construction of Mallannasagar, all the online reservoirs on the main trunk of Kaleshwaram Project are completed. These reservoirs will become growth engines to fire up the rural economy of Telangana,” an official explained.
Mallannasagar will also cater to the drinking water needs of Hyderabad by filling the two artificial reservoirs proposed on the outskirts of the city. Trial run for filling Mallannasagar, a much awaited event, has started on August 22, 2021 and it now has 10.50 tmcft water.
Out of eight pumps (43 MW each) installed at the reservoir, six are discharging 6,600 cusecs (0.66 tmcft/day) into Mallannasagar reservoir with a capacity of 50 tmcft. It was originally proposed to construct Tadkapalli reservoir prior to re-engineering of Pranahita Chevella Project with 1.50 tmcft capacity. After re-engineering, Tadkapalli reservoir capacity was increased to 50 tmcft and the Chief Minister renamed it as Sri Komuravelli Mallannasagar after local deity Komuravelli Mallanna in Siddipet district. Mallannasagar is the third reservoir among four online reservoirs in link-4 of Kaleshwaram Lift Irrigation Scheme.
Kaleshwaram Project, envisaged to meet the irrigation requirements of 18.25 lakh acres of new ayacut and 27.75 lakh acres of stabilisation under various existing projects like Sriram Sagar, Nizam Sagar, Singur, Vanadurga and hundreds of MI tanks which fall in the radar of Kaleshwaram Project.
Apart from irrigation, Kaleshwaram Project will also supply drinking water to villages enroute Hyderabad and also provide water for industries. To meet this huge requirement of water, a mother reservoir is essentially required having a large storage capacity. During the deliberations of re-engineering of Pranahita Chevella, this aspect was discussed at length and it was decided that Mallannasagar would be the “Mother Reservoir” because of its geographical advantage and water requirements to be met from Mallannasagar as well. This will be the second biggest storage reservoir in Godavari basin in Telangana after Sriram Sagar Reservoir.
There was criticism in some quarters over the enhancement of storage capacity of Mallannasagar to 50 tmcft from 1.5 tmcft during re-engineering of the project. The critics failed to go into the details of irrigation and other requirements under Mallannasagar as well as technical aspects. Hundreds of cases were filed in High Court and NGT on Kaleshwaram Project especially on Mallannasagar to halt the construction of the project. But the State overcame all the hurdles, one after the other.
Geographically Mallannasagar is located at higher elevation and at a ridge point which separates Godavari and Krishna basins. About 62 percent of Kaleshwaram ayacut falls within the radar of Mallannasagar reservoir. As pointed out by the Central Water Commission (CWC) that there was no adequate storage capacity for the erstwhile Pranahita Chevella, the TRS government redesigned the project and constructed the massive Mallannasagar.
Big reservoirs
The critics had argued that nowhere in the world such a big artificial reservoir was built without a self-catchment area. Though it is a fact that Mallannasagar is an artificial reservoir, it is not new in the combined State of Andhra Pradesh to construct such reservoirs. Many artificial reservoirs like Kandaleru Reservoir (68 tmcft), Gorakallu Reservoir (10 tmcft), Veligonda Reservoir (41 tmcft), Velugodu Reservoir (17 tmcft), Brahmamgari Matham Reservoir (17 tmcft), Owk Reservoir (7 tmcft) and Alugunuru Reservoir (3 tmcft) were built in the erstwhile AP on small streams as part of Jalayagnam Programme in Rayalaseema region with storage capacities much more than the yields of those local streams. Considering technical parameters and requirements, Mallannasagar capacity has been increased to 50 tmcft from 1.50 tmcft.
“With the phenomenal advancement of science and technology, now a large scale pumping of water is not a big issue. Telangana, due to various historical, political and geographical reasons has to depend invariably on big lift irrigation schemes. Hence, the large storage reservoirs are also essential in lift irrigation schemes in peninsular India where rivers receive inflows only during four months of monsoon,” sources in Irrigation Department explained.
The officials also refuted the ‘earthquake theories”. The officials, who prepared the DPR for the reservoir, meticulously studied the problems encountered in the design and construction of those high earthen dams before finalising the designs of Mallannasagar earth dam, sources said.
Huge capacity
The storage capacity of Mallannasagar is higher than those of the big reservoirs like Pulichintala (45 tmcft), Yellampalli (20 tmcft) and Mid-Manair (25.8 tmcft). However, the families affected by submergence were less in number in Mallannasagar, when compared to other reservoirs