<P> However, the available water resources at Tungabhadra dam are over-used, and water shortages are frequent . Water availability in the reservoir could be augmented by transferring water from the Krishna River, if a link canal were constructed from the Almatti reservoir to the Tungabhadra reservoir . Envisaging small balancing reservoirs where this link canal is intercepting the tributaries of Tungabhadra River would facilitate water diversion to Tungabhadra reservoir for augmenting further water availability . Once the Almatti reservoir FRL is raised to 524 m MSL, this canals full supply level (FSL) can also be increased to 516 m MSL from 510 m MSL to reduce its construction cost and serve more area for irrigation in Karnataka . </P> <P> Nearly 180 tmcft out of 230 tmcft water presently supplied from Tungabhadra reservoir to various canals can be replaced by reliable Krishna river water from the Narayanpur reservoir . These are water supply to mid and lower reaches of Tungabhadra left bank canal, water assistance to Rajolibanda canal, water assistance to KC canal and mid and lower reaches of Tungabhadra right bank low level canal . This is achieved with a 20 km long tunnel from Narayanpur reservoir to the Maski nala reservoir / tank situated at 475 m MSL for drawing nearly 250 tmcft Krishna river water . From this tank, north canal would supply Krishna river water by gravity flow to the lower reaches of Tungabhadra left bank canal in addition to bringing substantial uplands under irrigation in Karnataka and Telangana . From this tank, south canal would supply Krishna river water by gravity flow to the middle portion of Tungabhadra left bank canal in addition to bringing substantial uplands under irrigation in Karnataka and also connected to the Tungabhadra right bank low level canal at 425 m MSL near 15 ° 22 ′ 09" N 76 ° 32 ′ 55" E ﻿ / ﻿ 15.36917 ° N 76.54861 ° E ﻿ / 15.36917; 76.54861 ﻿ (Tungabhadra RB LLC) through a 1.5 km long aqueduct over Tungabhadra main river . Water is also released from the Maski nala in to downstream Tungabhadra main river to meet continuous water needs of downstream Rajolibanda canal and KC canal . 180 tmcft water in addition to the water diverted from the Almatti reservoir to Tunghbadra reservoir can be utilised for uplands irrigation in Tungabhadra basin and Rayalaseema region of Andhra Pradesh . When these joint projects of Karnataka and Andhra Pradesh are constructed, nearly 400 tmcft water additionally will be available for irrigation and drinking purposes in the high drought risk uplands of Rayalaseema and Karnataka . </P>

Tungabhadra dam lest its storage capacity due to