August 25, 2021 12:58:15 am
With monsoon delayed in Gujarat as August-end approaches, the depleting water reserves in the state have now become a cause of concern, especially since even the catchment areas of the Sardar Sarovar Narmada Dam, which is the lifeline of the state, has recorded barely any rainfall in August.
The rainfall deficit in Madhya Pradesh, where a majority of the Narmada basin is located, has meant an almost negligible inflow of water to the Sardar Sarovar Dam that stands at 115.82 metres, on August 23, which is just five metres short of its dead stock, which last year, at this time, was 120 metres.
According to the Sardar Sarovar Narmada Nigam Limited (SSNNL), which manages the dam, the cut back on the supply is inevitable in the coming days. Currently, against an average inflow of 17000 cusec, the dam is releasing a total of 12000 cusec for irrigation and drinking water, according to ML Patel, Superintending Engineer of SSNNL, but the farmers have been told to use water “sparingly”. On August 23, the dam recorded an inflow of 21,298 cusec and an outflow of 14,753 cusec.
Patel told The Indian Express Tuesday, “There is a delay in the monsoon and the deficit in rainfall in Madhya Pradesh has meant a low inflow into the dam this year. At the moment, we are releasing water for irrigation as well and we will be able to save the monsoon Kharif crops. We are clear that the crops that are standing right now will not be damaged. There will be no crisis of drinking water as well because we have decided to judiciously distribute the water until the levels rise. If needed, the dead storage below 110 metres will also be used (as the dam did in 2017) but we still do not expect the situation to be that grim. We are also telling farmers to use the water sparingly as needed. The Riverbed Powerhouse (RBPH) is shut in order to save the water.”
The powerhouses of the Narmada Dam usually remain operational in the monsoon — for the last three years since 2018, the dam began releasing water by mid-August along with fully functional RBPH and Canal Head Powerhouse (CHPH), in order to maintain balance. Officials of SSNNL say that the closure of the RBPH means a loss of close to Rs 7 crore of electricity generation per day, which is a dent to all three states sharing the power from the Dam — Gujarat, Maharashtra and Madhya Pradesh.
In the upstream reservoirs in Madhya Pradesh, the Indirasagar Dam (ISP), which has a Full Reservoir Level (FRL) of 196.60 metres is full up to 194.82 metres, as of August 23, while the Omkareshwar Dam, which has an FRL of 262.13 metres stands at 252.58 metres. By the beginning of August, the two dams release surplus water along with the generation of power from their respective hydropower stations. However, the break in the rainfall in August in the catchment areas has caused a deficit in the outflow of the water from both dams.
While ISP has received a total rainfall of 459.2 mm this season, Omkareshwar has received a total rainfall of 429.2 mm this season, so far. All 38 rain gauge stations, including Sardar Sarovar, have barely recorded rainfall since the beginning of July — with almost no rainfall recorded since August 5 at most rain gauge stations, as per the hydrology data of the current monsoon of the Narmada Basin.
However, officials of SSNNL are hopeful that the erratic pattern of monsoon will continue this year and bring along a heavy rain spell soon. Patel said, “The monsoon season lasts until October. We have seen that in the few years, for a part of the monsoon, we receive heavy rains along with the upper catchment area and it is sufficient to raise the level up to the FRL.”