by V V Balakrishna
Hyderabad:
Andhra Pradesh chief minister N Chandrababu Naidu will meet his Karnataka counterpart Siddharamaiah in Bangalore on Monday with a request to the latter to increase the height of Tungabhadra dam by two feet so that the Rayalaseema will get sufficient water.
A memorandum has been prepared by AP irrigation department to that effect to be submitted to the Karnataka CM.
According to sources, Naidu will also request the Karnataka government to construct a parallel high level canal (HLC) to draw 20 to 25 tmc water from Tungabhadra in flood period.
Tungabhadra Project was constructed in 1953 at Mallapuram in Bellary district with a storage capacity of 132.471 tmc of water to provide irrigation facilities in Raichur and Bellary districts of Karnataka and Kurnool, Kadapa, Mahbubnagar and Anantapur districts of erstwhile Andhra Pradesh.
Siltation and less utilization of water: As per the hydrographic surveys conducted during 2008, the storage capacity of the reservoir has come down to 100.855 tmc against original storage capacity of 132.471 tmc due to progressive siltation.
Accordingly, the annual utilisation of water is reduced considerably to 106 - 175 tmc against 212 tmc. Consequently, the prorata entitlement for various systems in erstwhile Andhra Pradesh has also reduced to 40 - 62 tmc. The prorata entitlement to TBPHLC system has also reduced to 16 - 27 tmc against allocation of 32.50 tmc.
The total length of RBHLC is 196.43 km. The initial length of 105.437 km runs in Karnataka and is under TB Board’s jurisdiction i.e., up to where it enters the Andhra Pradesh territory.
The RBHLC is designed with a capacity of 4,000 Cusecs at head and to deliver 2,575 Cusecs at AP Border so as to deliver 32.50 tmc to Andhra Pradesh under HLC System. However, RBHLC is not in a position to carry a discharge of more than 3,400 cusecs at its head and the maximum discharge at AP Border is 1,800 cusecs.
There is a shift to water intensive crops like paddy, sugarcane etc. as against less water intensive crops. Hence, there are forcible overdrawals at the distributary off-takes. This is causing short fall of indented water to the tail end reach i.e. AP border. There are number of cases of damages and forcible overdrawals having been lodged regularly with the local police and revenue authorities. So, there is a need to relocalise the ayacut in the upper part of the canals, the AP government felt.
In view of the practical difficulties faced, it is very clear that unless the RBHLC is modernised, it is not possible to draw the designed discharge of even 4,000 cusecs at head. As a result the allocated quantum of 32.500 tmc share of Andhra Pradesh cannot be realised, the AP contended.
AP contended that the modernisation of HLC in AP territory at cost of `463.5 crore would allow them to draw 42.5 tmc. So far, about 50 per cent work is completed and entire work is proposed to be completed by 2015-16.
Of the total length of RBLLC is 348.20 km and the initial length of 250.58 km is under TB Board’s jurisdiction.
Likewise, the modernisation of LLC in AP area with a cost of `179 crore would enable AP to draw more water.
Parallel High Level Canal: The average utilisation for the past 20 Years in HLC system is only 26.75 tmc against the allocation of 42.50 tmc (32.50 tmc + 10 tmc diversion of KC Canal quota) and hence, a parallel High Level Canal is proposed to draw water during flood time, the AP CM will inform his Karnataka counterpart.
This envisages realisation of 20 to 25 tmc of water in a period of 25 to 30 days when the reservoir is in surplus and the quantum is within the KWDT allocation.
The parallel canal proposed with a carrying capacity of 12,000 cusecs, will traverse approximately 200 km. The tentative cost of the scheme is about ` 4,500 crore.
However, consensus on taking up detailed feasibility study of the parallel canal could not be arrived at so far, even though it was under discussions in the Board meetings since December, 1997.
Raising the height of dam: It is proposed to raise the height of the dam by two feet so as to compensate the loss in storage due to siltation of the reservoir, Naidu will tell Karnataka CM.
Allocation of Water in TB Dam (in tmc)
State - Gross
Allocation - Evaporation
Losses - Net Allocation
Karnataka 151.49 12.50 138.99
AP 72.00 5.50 66.50
Telangana 6.51 6.51 -
Out of 66.50 tmc of net allocation for Andhra Pradesh, the allocation to various systems is:
TBP High Level Canal (HLC) 32.50 tmc
TBP Low Level Canal (LLC) 24.00 tmc
KC Canal 10.00 tmc
No comments:
Post a Comment