Development of an analytical function for optimizing the capacity of spring water storage structure

Now, there is no doubt that the Greater Himalayan region is facing the impact of climate change and that is specifically visible through the noticeable changes in the discharging patterns of the springs from the last four to five decades. Either the springs have become seasonal or their discharge rates (particularly during recession periods) have diminished to significant extent. In this changing scenario, the long-term survival of the inhabitants in the region vests in the adaption of suitable water management practices; and the most feasible option is to reserve the water stock when it is in excess during monsoon/post-monsoon season. However, the construction/purchase of water storage structure may become highly uneconomical for below mid-class families if the selected capacity of the structure is more than optimal. On the contrary, the undersized (than optimal capacity) will fail to serve its purpose. Thus, for accurately optimizing the capacity of water storage structure, an analytical function has been proposed in the present study. The application of the proposed function has been demonstrated by considering the realistic number of dependents on a western-Himalayan gravity spring named ‘Fakua’. The analyses show that with increase in the water shortage period, per cent reduction in the optimized storage from the actual demand decreases and this particular behavior depends on the spring discharge rate during recession period. With the use of formulated analytical function, the available discharge from the spring during recession period can be managed much more efficiently and economically in comparison to other flow mass curve methods.