Sardar Sarovar Dam’s sudden water release flooded parts of Gujarat, suggests analysis
An analysis by the South Asia Network of Rivers, Dams and People said no water was released by the barrage until August 29, despite warnings from the IMD that there has been exceptionally heavy rainfall in the Narmada basin’s upstream since August 25Updated: Sep 29, 2020, 11:40 IST
An analysis by the South Asia Network of Rivers, Dams and People (SANDRP) has suggested that severe flooding in Gujarat’s Bharuch, Narmada and Vadodara districts from August 29 to September 2 had occurred because of sudden release of massive quantities of water from the Sardar Sarovar Dam (SSD).
This has led critics and supporters of the dam writing counter arguments on online portals on the role of SSD in causing floods in Gujarat in early September.
SANDRP, which has analysed the SSD’s water release data, said that no water was released from the dam spillway until August 28, despite information from the India Meteorological Department (IMD) that there has been exceptionally heavy rainfall in the Narmada basin’s upstream since August 25 and earlier.
“What we saw this time is a worrying trend. SSD couldn’t ration its water release based on information of extreme rainfall in the Narmada catchment area. There was large scale devastation primarily because of sudden water release by the dam. Hundreds of people had to be shifted from Bharuch and Vadodara districts during the flooding.
I fear that more such dam generated floods will affect the region in the future,” said Himanshu Thakkar, coordinator, SANDRP, and an engineer, who was earlier associated with the Narmada Bachao Andolan (NBA). The analysis suggests that though no water was released by the dam after extremely heavy rains started in the Narmada valley districts, the dam started releasing up to 10 lakh cusecs from the night of August 29.
“Three days later, on September 1, they closed most of the spillway gates, which reduced releases from spillway to less than a tenth of the earlier figure. From August 29 to September 1, massive quantities were released, up to 30, 000 cumecs through spillways, and almost nothing before or after. It created massive flood disasters all along the downstream from Gaudeshwar to Chandod to Bharuch,” Thakkar said.
SANDRP, in its analysis published on their website, said the SSD authorities might have ignored both Central Water Commission’s (CWC) warnings and IMD’s rainfall forecast.
The first heavy spell of rainfall in the Narmada basin had occurred between August 16 and 18, followed by more precipitation on August 21 and 22.
However, an exceptionally heavy spell of rainfall was recorded from August 26 onwards.
On August 27, Madhya Pradesh’s (MP) Narsinghpur had recorded 152.6 millimetres (mm); Raisen (110.5 mm); Hoshangabad (81.8 mm); and the following day Betul recorded (142.4 mm); Harda ( 111.1 mm); and Hoshangabad (191.1 mm).
On August 28, the CWC in its flood forecast had also warned that the SSD was expected to receive increased flows due to very heavy rainfall in the past three days leading to a rise in the water level of Narmada, Mahi, Sabarmati and rivers flowing in the westward direction in Gujarat. CWC had tweeted on September 1 that “heavy inflows are still continuing at Indirasagar, Omkareshwar and SSD. Releases from SSD gave rise to severe flooding situation at Garudeshwar in Narmada and Bharuch districts.”
SSD is one of the largest water resources projects in the country that covers four major states such as Maharashtra, MP, Gujarat and Rajasthan.
“At the outset, let me make it clear that SANDRP is quite known for its anti-dam stand in general and anti-SSD in particular,” said MB Joshi, chief general manager (technical & coordination), Sardar Sarovar Narmada Nigam Limited.
The 1,163-kilometre (km) stretch of river Narmada -- from its source at Amarkantak to SSD – had recorded heavy rainfall from August 20 to September 1.
Around 14,660 million cubic metres of water were received at Indira Sagar as against its live storage capacity of 9,745 million cubic metres. Indira Sagar is the largest dam in the Narmada river basin, according to SSD authorities.
SSD had to negotiate huge releases of water from the upstream major dams such as Omkareshwar and Indira Sagar because of heavy rainfall.
“Keeping in view the safety of the dam as well as the people in Bharuch city and about 30 villages on the banks of Narmada, the reservoir was operated in a scientific way following the established principles of flood routing in major dams,” the SSD said.
The SSD authorities cited that SANDRP’s report is factually incorrect because no water was released by the barrage until August 29. The River Bed Power House (RBPH) operation was started from midnight on August 25 and it gradually gained momentum.
“Efficacy of SSD in flood control is evident from the fact that despite continuous heavy inflow of over 10 lakh cusecs of water received for about 62 hours -- between 6 pm on August 30 to 11 pm on September 1 -- spillway release of more than 10 lakh cusecs could be restricted after 21 hours,” and “inflow at Sardar Sarovar went up to as high as 12.06 lakh cusec on August 31. However, the maximum spillway discharge released was 10.74 lakh cusec after considering the fact that any release from the dam further gets added due to flow from tributaries joining in the downstream,” the SSD authorities said.
Four retired Gujarat government officials, including two chief engineers and a secretary of the Gujarat government, responded to SANDRP’s analysis in the Counterview portal.
“Some well-known activists, who are anti-dam in general and anti-Sardar Sarovar in particular, have been still attempting to curse the SSD and its project authorities by making false allegations of having created ‘avoidable flood disaster’. Instead of allowing the public in the downstream areas to share their experience of having a great sigh of relief this year amid very heavy rainfall in the Narmada basin, factually incorrect information is being deliberately disseminated,” they argued against SANDRP’s assertions.