When Prime Minister Modi inaugurated the Sardar Sarovar Dam with much fanfare in September 2017, he had not thought that within a few months it would prove to be a gigantic folly as predicted all along by the Narmada Bachao Andolan. There is now not enough water in the dam and the river has become dead downstream of it. A year later as he once again indulges in fanfare to inaugurate another huge folly, he will yet again be ignorant of the extent of the blunder and its future deleterious consequences. The roots of these follies lie in the history of the faulty planning of the Sardar Sarovar Dam.
A bitter dispute over the sharing of the water in the Narmada between the states of Madhya Pradesh, Maharashtra and Gujarat eventually resulted in a political agreement in 1974 that the annual yield of the river available at Navagam, the site of the Sardar Sarovar Dam, should be taken as 34.5 billion cubic meters (bcm) at seventy five percent dependability. Of this 0.31 bcm was to be allotted to Maharashtra, 0.62 bcm to Rajasthan, 11.1 bcm to Gujarat and 22.5 bcm to Madhya Pradesh. This political settlement estimated the annual yield of the Narmada at Navagam at seventy five percent dependability at a value well above the assessment by the technical experts of 27.4 bcm. Due to paucity of river flow measurement data even this lower technical estimate of yield of the Narmada river at Navagam was flawed because it was based on arbitrary assumptions for the values of the surface runoff, evaporation losses at reservoirs, return flow from upstream storages and from the groundwater aquifers and the carryover storages without doing any detailed sampling and simulation studies to properly estimate these values.
Today, the actual flow in the river Narmada is even less. Due to secrecy maintained by the Central Water Commission about the flow measurement that it is doing, it is not possible to independently estimate what is the current flow. Given the massive deforestation that has taken place and the heavy development of groundwater irrigation in the catchment area, the flow in the river has decreased considerably from that prevailing earlier. So even though the full reservoir level of the Sardar Sarovar Dam is 138.7 m, the actual water level at the end of the monsoons is only 127 m. Thus, the dam is only half full. This was the case last year also and is likely to be the case in future too, given the much lower actual flow in the river compared to the design flow. As the flow in the canal starts for providing water to farms, industries and towns, the water level will quickly come down to the minimum drawdown level of 110.6 m and there will be little water flowing in the canal leaving the farmers in Gujarat literally high and dry. Like last year they can only look apprehensively towards a spring and summer of discontent.
What is of much greater concern is that there will be very little water flowing in the river downstream of the dam. The many dams in Madhya Pradesh upstream of the Sardar Sarovar have stored up most of the flow and that state is saying that since it is not getting the stipulated 22.5 bcm that is allotted to it, there is no question of releasing water to Gujarat!! Consequently there is almost no flow in the river below the Sardar Sarovar dam once the monsoons are over apart from the little that flows through the river bed power house after generating electricity.
So first a huge dam is built based on unrealistic flow estimates and then a huge statue is built based on misplaced priorities and the compounded folly leads to the Sardar left surveying a dead river.