With most parts of the state receiving a spell of rain over the last few days, the Sardar Sarovar Narmada Nigam Ltd. (SSNNL) has begun “filling up” the dam reservoir by reducing the running of the Canal Head Power House (CHPH) to a minimum as per the drinking water needs of the state.
The SSNNL, which had closed the Riverbed Powerhouse (RBPH) of the dam in July due to the non-availability of water, is now focused on raising the level of water in the reservoir to see through the summer next year.
On Saturday evening, the Sardar Sarovar stood at 119.61 metres. The level has increased from 117.66 metres on Tuesday due to a planned management strategy to fill up the reservoir by reducing the outflow of water from the dam after generation of power.
The operations of the CHPH were lowered in phases since the beginning of September, when four of the five 50MW turbines operated on September 1 and generated power of 1.9 Million Units (MU) of power.
The CHPH then ran only two of its turbines until September 7 and since has been running only one turbine to generate an average of 0.4 MU of power every day. SSNNL officials said that the operations of the CHPH are decided on the basis of the need for water downstream.
An official said, “We have had good rains for the last four-five days so we have stopped irrigation water supply through the main canal. We are only operating CHPH for drinking water and domestic use, the need for which is about 4000 cusecs of water. That is met by running the CHPH for a minimum time”
The official added that the SSNNL had decided to close the RBPH, which has six reversible turbines of a total installed capacity of 1200 MW since July, owing to the depleting reservoir as it is not mandatory to generate hydropower when the basin is in deficit. “The basin should have about 7000 cusec water per turbine of the RBPH per day to be able to generate RBPH. So far, we do not have so much water for operating RBPH this year. All partner states need electricity to balance the grid,” an SSNNL official said.
While the generation of hydropower at the RBPH and CHPH together helps stabilise the grids in Maharashtra, Madhya Pradesh and Gujarat, the Narmada Control Authority has considered that over a period of time following the completion of the canal networks in the partner states, the power generation from the Sardar Sarovar Dam would drop down to nil.
The SSNNL official said that the Narmada Control Authority (NCA), which oversees the implementation of the decision of the Narmada Water Disputes Tribunal (NWDT) will calculate the final share of the water to be received by Gujarat this water year in November, as against the 9 Million Acre Feet (MAF) of the basin that Gujarat is entitled to.
The official said, “The water year is counted from July 1 to June 30 every year and the share of water to be distributed between Gujarat, Rajasthan, and Maharashtra is decided on the basis of the availability of water in the Narmada basin. In a year, when the rainfall is normal and the basin has 28 MAF water, Gujarat gets a share of 9 MAF. However, this share is calculated at the end of the monsoon season in November.”
SSNNL Managing Director Rajiv Gupta told The Sunday Express, “The CHPH operations are done based on downstream needs. Presently, it is being run for a drinking water supply. The recent spell of rains in Saurashtra doesn’t necessitate any extra running.” On Saturday, the Narmada dam was receiving an inflow of about 20000 cusecs from upstream and releasing about 4500 cusecs, officials said.