IRRIGATION PUMPING PROJECT ON GODAVARI RIVER

– T. HANUMANTHA RAO

T.Hanumantha Rao

Chairman, Technical Committee,                                                       H6-3-S83 A/11, Punjagutta,

Water Conservation Mission, Government of A. P.                                     Hyderabad - 500 082.

United Nations (OPS) Consultant for Asian Countries.                                    Phone: 23402048.

About two decades back it was felt that it is not possible to fully utilize the available 800 TMC of Godavari water out of the allocated water to Andhra Pradesh. Even if reservoirs have to be constructed water level in the same would be at about 100 meters above Mean Sea Level (MSL) and bulk of the area in Telangana to be irrigated would be available between levels 200 and 400 MSL. The average head of pumping in such a case would be 150 meters. It was then considered financially not viable to pump a quantity of nearly 600 TMC for irrigating these areas. This is the reason that projects like Ichampally were designed for gravity flow irrigation using 80 TMC and the rest for generating hydropower. If water has to be pumped for an average height of 150 meters, power consumption alone would workout, (at the rate of Rs.3/- per unit), to Rs. 10,700/- per acre (for supplying 900 mm depth of water), for Kharif wet crops. For Kharif ID crops, for three wetting and 150 mm depth of irrigation, the power consumption charges would work out to Rs. 1,780/- per acre. For Rabi ID crops to give ten wettings (total 500 mm depth) the cost of power requirement is Rs.5,940/- per acre. These power consumption charges are exorbitant. Neither the farmer nor the government subsidy would be able to sustain the system. If a dedicated thermal power station is built, exclusively for the purpose of supplying the required power and capital expenditure is charged to the irrigation project, the cost of consumables like coal and other maintenance charges would workout to Rs.1.50 per unit. On this basis, the power charges would become half of the above mentioned figures, namely Rs.5.3507- per acre for Kharif wet, Rs.890/- per acre for kharif ID. Rs.2.970/- per acre for rabi ID even these figures are extremely high and the farmers will not able to bear this expenditure in addition to other costs of pumping.

In the existing lift irrigation schemes constructed by the Irrigation Development Corporation nearest 50% of the- scheme (157 out of 320) have become defunct on account of the farmers not in a position to pay the electric consumption charges. This is the situation when the average head of pumping is only 30 meters. If the head of pumping is five times of this, it can easily be concluded that the system is not sustainable on its own. It is also not possible for the government to give huge subsidies every year. Thus the lift irrigation projects now contemplated on Godavari river (e.g. Devadula) would not be sustainable if the average pumping head is 150 meters. A method has to be found out for providing almost free power, out of the Godavari system, to enable pumping water (irrigation) for such high heads. The power resources will have to be generated through hydropower within the Godavari basin and the cost of the hydro power stations will have to be charged to the irrigation project. Since there are no consumables and the maintenance charges for the same would be nominal, they can be merged with the irrigation maintenance and almost free power can be supplied. The enable this, 3 reservoirs will have be constructed across Godavari. It is possible to generate 3400 megawatt of power through four barrages and three dams across Godavari river. This would be adequate to meet the requirement of 2900 megawatt to utilize 760 TMC of Godavari water. The three reservoirs can be located at (a) Suraram between confluence of Pranahita and Indravathi rivers, (b) Down stream of Kantalapalli near Eturunagaram, (c) Polavaram. The four barrages would be at (a) near Peddaballal down stream of Kadam river confluence, (b) Yellampalli, (c) Upstream of Edira, (d) Dummagudem. These four barrages would be able to generate 1000 megawatt of power during- kharif period. A capacity of 2400 megawatt can be generated during the kharif period in the three reservoirs.  The whole system of barrages and reservoirs would be able to generate 1000 megawatt of power during the rabi period when water is led down for Godavari delta. The power of 3400 megawatt during the kharif can be used for irrigating 46  lakhs acres of kharif wet crops and the rabi reason power of 1000 megawatts cab be utilized for irrigating rabi ID crops for an extent of 23 lakhs acres.

Lift irrigation projects of huge magnitude on Godavari river should not betaken up for execution, unless the same are tied up with hydro electric projects. This is the only method that would make possible, the utilization of the balance 760 TMC in Godavari river, presently being wasted to the sea.

Unless free power is provided for the Godavari pumping projects the systems can not be financially viable either to the farmers or to the government.