Cheluvaraju R.,KNNL |
Water and Energy International | Year: 2014
Though Karnataka is endowed with vast water resources of about an average of 97,450 Million Cum of yield annually, owing to uneven distribution of rainfall and vagaries of monsoon, many parts of Karnataka are facing acute shortage of drinking water and a large tract of land has become arid/semiarid. It is pertinent to note that two-thirds of its geographical area is under arid /semiarid conditions and stands second only to Rajasthan in the country in drought prone area. Due to over exploitation of groundwater in Kolar, Tumkur, Chikballapur and Bangalore rural districts, the water table has reached alarming depths of 25 m-40 m below ground level. The situation is further exacerbated by the increased content of harmful salts like fluorides and nitrates. To mitigate the acute shortage of drinking water and health hazards caused by nitrate and fluoride contamination in the drinking water, Government of Karnataka initiated and commissioned several Schemes. Owing to lack of sufficient source of water, Schemes implemented such as Paragodu, Wardhaman, Markandeya, Manchanabele and Projects from tanks in Tumkur district have not met the desired results. This necessitated in identifying an independent and sustainable source free from interstate dispute. West flowing rivers with an average annual yield of about 56,657 Million Cum are identified as the sources available and Yettinahole Project is the only viable and sustainable solution to supply drinking water to the western districts of the State with minimum environmental impact. In formulating the Project, there are many issues to be addressed and challenges to be overcome. The issues involved are assessment of divertible yield, environmental impact, land acquisition, forest acquisition, storage, conveyance and distribution of water. One of the challenges faced is in the design and execution of lifting arrangements with very high capacity volute pumps specially designed to pump large quantum of water of about 680 Million Cum from June to November every year to meet the drinking water requirements of 29 talukas of 7 districts for the whole year. The execution of lifting arrangements is very difficult in a terrain where the annual rainfall is as high as 6,000 mm. The Karnataka Neeravari Nigam Limited (KNNL) which is implementing this Project has to overcome the agitation of the public of the western ghats who apprehend that the diversion of west flowing water to the east would affect the environment and cause shortage of water to them. This paper attempts to dispel the apprehensions in the minds of public. The project has least environmental impact, does not cause degradation of the Western Ghats in any manner and would provide drinking water to a large population of the eastern districts (68.35 lakhs), thereby improving the economy of the area and the State. © 2014, Central Board of Irrigation and Power. All rights reserved.