Minimum Environmental/Ecological Flows - Views of CWC

National Water Policy (2012) duly recognizes the ecological needs of the river setting aside a portion of river flows on the pattern of natural flow regime and environmental management plan is an integral part of planning of any water resources development project. The detailed environmental studies are required to be carried out including requirement of e-flows while planning any water resources project. However, the estimation of environmental flows is still a challenge primarily due to lack of both the understanding of and quantitative data on relationships between river flows and ecological characteristics of river. The assessment of environmental flows rationally keeping in view of limited water resources and dependence of livelihood of large population is still at infancy stage. Various studies show wide variations in the assessment of E-flows. The main challenge is to meet the e-flow requirement during lean period. There is claimer from various groups to reserve the majority of river flows for e-flows during lean period. However, the allocation of water for environmental needs should not be decided in isolation. The water requirements of other demands of food, energy, livelihoods etc in the basin should also be taken into account while allocating scares water resources to various competing users including environmental needs. The paper discusses the developments in field and views of CWC on the issue.