Laxmi Padhi, 75, has spent her entire life by the banks of Mahanadi. The mother of all rivers in Odisha passes by her village Badhila in Sonepur district and she is not happy with what her experienced eyes have observed of late.
The river doesn’t flow the way it used to. It still runs through a massive 851 kms through Chhattisgarh and Odisha before ending its journey in the Bay of Bengal. But for those who depend on it for a livelihood reckon this is not the same force. Some blame irrigation projects, some blame faulty designs, as people who live by the river note with sadness what they see is not what it was.
“The river is not what it was in my younger days, or for that matter, two decades ago. The fury of Mahanadi is gone,” says Padhi. Further downstream, at Boudh district’s Manamunda, Prakash Meher has similar views, which is echoed by villagers in Dhama, Larasara, Jamtikra, Kapasira and Deogaon in Maneswar block of Sambalpur district.
For many, this is not just a river. It’s a source of life. Water for irrigation and other purposes, fishery — their existence is defined by Mahanadi. For them, Mahanadi is not a game the governments of two States appear to be playing. Odisha has accused Chhattisgarh of obstructing the river’s flow and blamed the Centre for turning a blind eye. Denying this, Chhattisgarh has called for better management.
That Chhattisgarh has built eight major and 29 medium irrigation projects in the upper catchment of Mahanadi has left the Odisha administration sleepless. Construction of six barrages on the main arm of the Mahanadi, just upstream of the Hirakud, have been taken up. It is also contemplating construction of a reservoir dam in Kelo river adjacent to the Odisha border.
The impact of these six industrial barrages will be immediate on the availability of water to Hirakud dam, which controls the lives of millions in Odisha. Completed in 1957, it is one of the first multi-purpose dam projects, but not without controversies. Its decay due to heavy siltation has been an old concern. An analysis by Central Water Commission in 1995 and studies by dam authorities soon after revealed that its total storage capacity had gone down by 27.35% due to siltation. A remote sensing survey has put the total amount of silt deposited in the gross storage at 2,209 million cubic metre. Gross storage in 2000 was reduced by 53.72%, live storage and dead storage declined by 17.16% and 53.72%.
Ranjan Panda, noted water rights activist and researcher, apprehends that siltation must have affected nearly 40% of the reservoir, although there is no study on this. This could mean the dam will not be fully functional in the near future. “Unless measures are taken, which is almost impossible as far as de-silting is concerned, the dam is going to stop most of its important functions in 15-20 years,” he says. Panda thinks it has been caused by faulty design.
The original project report had suggested de-silting by flushing out water during rainy seasons and maintaining reservoir level at 590 feet (dead storage). This is not possible, as it would compromise Hirakud’s primary objectives – irrigation and power generation.
Ex-Chief Engineer and Basin Manager of Upper Mahanadi Basin, Sudhakar Patri maintains there has been 17% reduction in storage capacity and siltation has grown 2.5 times faster.
Allaying fears of early death of the dam, Patri says “trap efficiency” is responsible for faster sedimentation. He admits that the dam’s utility will be reduced in flood control and power generation in non-monsoon months. “The government must think of decommissioning the dam by preparing an alternative plan that keeps the irrigation and drinking water functions afloat,” he suggests.
But a study by IIT Madras and Bombay recently found that Mahanadi’s water yield has decreased by 10% due to low rainfall. Sub Divisional Officer, Hirakud Dam Project, Ashwini Choudhury says this year, water level in Hirakud Dam Reservoir is 612.89 feet, two feet more compared to last year. Panda says this claim is opposite to what authorities said earlier. In a letter to Water Resources Department on Jan 20, authorities claimed that the December 2016 inflow was 33% less compared to the average from 2005-2015 for the same month.
This, Panda says, was done to make the government’s case in Supreme Court against Chhattisgarh stronger.