give to argent in favour of Small dams over large dam
Answers
Developing small dams had never been the priority of successive governments. Since 1996, there had been no significant addition to small dams though a number of schemes were planned. The successive governments failed to focus on small dams’ construction, in spite of much scope in all the provinces. Though considerable experience in planning, design and construction of small dams is available locally since the 60s, it has not been utilised effectively. In every province, Small Dams Organisation continues to function, with supporting technical staff as an arm of irrigation department.
But the planners’ focus has always been on developing large and mega water projects, which are too costly and require long lead-time, bear negative impacts on large-scale population dislocation, other social and environmental concerns and have political dimensions too. These projects, costing multi-million dollars and requiring at least 10 to 12 years for completion, often run into snags and are delayed. The cost of two options may be visualised from the fact that 12 small dams in the Potohar region were completed in 1996 at a cost of $35.4 million, whereas Diamer-Basha dam is estimated to cost $8.5 billion.
Construction of large dams, which is feasible only in far-flung and isolated areas, faces communication and logistic problems and limitations of availability of labour. The development of infrastructure for large dams is consequently an expensive proposition, besides being totally dependent on foreign sources for dam construction.
Thus, local community-based small dams provide a simple, cheaper, reliable and manageable solution to water storage issues. Typical examples are cited of four small dams, Rawal, Simli, Misriot and Tanaza, which meet effectively water requirements of Rawalpindi, Islamabad and surrounding areas.
Nevertheless, small dams are not an alternative to large dams and mega multi-purpose water projects and can be considered of supplementary or complimentary nature. However, small dams are equally important to store and conserve water for increasing irrigation and drinking water sources and improving socio-economic conditions of the area. Also, small dams may not result in sustainable development of agriculture, in contrast to large dams, but its impact on groundwater development is positive.
Pakistan has constructed in all 58 small dams so far. According to reliable estimates, it has the potential to build another 750 small dams to meet water requirements of growing local and regional population. The trend in favour of small dams is being pursued in the developing countries. Sri Lanka has constructed some 12,000 small dams and Nepal more than 2,000. In India, which is considered a leading dam builder, 19,134 small dams have been developed and 52 small dams would shortly be constructed on Chenab and other rivers originating from Kashmir.