Assessment of environmental flows for the upper Ganga basin

One of the key threats to the upper Ganga and other Himalayan rivers is water abstraction for hydropower, irrigation, urban and industrial needs. To address this, the concept of ‘minimum flows’ has recently been proposed and is being
implemented in some river basins. However, this is still not based on a full understanding of the regime of flows needed in a river to maintain its ecological integrity as well as support human needs. It was this gap in a holistic approach to
Environmental Flows (E-Flows) that led WWF-India to initiate a program to develop and test a methodology for determining E-Flows for the Ganga. In 2008, a team from WWF, along with key partners and experts initiated the task of examining and adapting existing global E-Flows methodologies to develop an appropriate approach for a river as complex as the Ganga. This involved integrating various aspects of the river – social and livelihood needs, cultural and spiritual requirements, hydrology and hydraulics, geomorphology, water quality and biodiversity values. The approach to assess E-Flows for the Ganga was developed based on the Building Block Methodology which had to be adapted to include the unique cultural and spiritual values of the river. This report “Assessment of Environmental Flows for the Upper Ganga Basin” captures the journey, the outcomes and the lessons gathered over the last four years of this work.