The tendency of filling up reservoirs in the beginning and middle of monsoon season have been leading to avoidable flood disasters in the country. Apart from Kerala flood 2018, which was aggravated by mismanagement of reservoirs, various reports show that reservoirs in river basin of Cauvery, Krishna, Godavari and Ganga were also filled up well before the end of South West monsoon season. Resultantly there were many man made flood spells in downstream areas affecting lives and livelihoods of people.
After highlighting role of dams in floods in Kerala and how improper dam operation affected people in Assam and Himachal Pradesh, this third and concluding part throws light on other dam induced flood (and canal breach) incidents in 2018. Continue reading “Dams Floods 2018: Filling up Dams well before Monsoon end, Invitation to Disaster”
Dams and reservoirs make rivers sediment-starved and menacing manifold downstream. While heavy rainfall is also a key factor behind the floods, hungry water had a more pronounced effect, says D. Padmalal, Scientist and Head, Hydrological process group, National Centre for Earth Science Studies.
– “When the sediment transport is interrupted, the potential energy of the hungry water released from dams will scour the river banks downstream, uprooting trees or riparian vegetation and damaging bridges and other engineering structures,” explains Dr. Padmalal. Overloaded with silt and clay from the eroding river banks, the highly turbid and viscous water clogs drainage channels. Subsequent discharge of water from the dam will lead to inundation and waterlogging of large areas.
– Hungry water can also develop in high gradient river channels devoid of adequate quantity of sand and gravel, especially during periods of high rainfall. “Years of uncontrolled sand mining have left most of the rivers in Kerala depleted or exhausted of sand and gravel. This creates a situation similar to the release of hungry water from dams,” notes Dr. Padmalal. When the river channel has adequate supply of sand and gravel, the potential energy of the water is used to transport the mixture. The water does not scour the banks or turn muddy.
Continue reading “DRP News Bulletin 1 October 2018: Hungry Water Effect due to Dams & Unsustainable Sand Mining Worsened Kerala Floods”
Traditionally, our river management strategies are mainly focused on the water flows, including flood management, and these have resulted in various interventions such as dams, barrages, canals and embankments. Most of these interventions have had very little consideration for sediment transfer and even if they did, they were generally defunct within a few years of their operations either due to improper design or inadequate maintenance.
A long-term sediment management strategy has never been a part of any protocol of river management, not just in India, but in several other parts of the world. It is amply clear that sediment management must form an important component of management strategies for the Himalayan rivers. The Union Water Ministry has recently circulated a draft policy on sediment management.
Continue reading “DRP News Bulletin 13 August 2018: Existing Sediment Management Draft Policy Promoting Navigation & Not Rivers’ Health”
DURING FEB 25-26, 2017, A LANDMARK MEETING HAPPENED IN PATNA, ORGANISED BY BIHAR GOVERNMENT, UNDER THE LEADERSHIP OF CHIEF MINISTER SHRI NITISH KUMAR. THE MEETING WAS ON INCESSANT GANGA WITH SUBTITLE “CAN WE ACHIEVE CLEAN GANGA WITHOUT INCESSANT GANGA?”. THIS NATIONAL-INTERNATIONAL CONFERENCE WAS LANDMARK MEETING FOR A NUMBER OF REASONS, BUT MOST IMPORTANTLY, SINCE A STATE GOVERNMENT WAS TAKING THE LEADERSHIP FOR THE CAUSE OF THE RIVER GANGA. WHILE THE CONFERENCE WAS FOCUSSED ON ACHIEVING A REJUVENATED GANGA, I WAS TO SPEAK ON THE WAY FORWARD ABOUT THE FARAKKA BARRAGE, A KEY OBSTACLE IN THE PATH OF REJUVENATED GANGA. FOLLOWING IS MY LETTER TO BIHAR CHIEF MINISTER, FOLLOWING THE CONFERENCE, WHICH CONTAINS MY RECOMMENDATIONS TO THE BIHAR GOVERNMENT. THESE RECOMMENDATIONS WERE APPARENTLY ACCEPTED IN THE FINAL SESSION.
March 2, 21017
Shri Nitish Kumar,
Chief Minister of Bihar,
Firstly, I would like to thank you and Water Resources Department of Bihar for inviting me to the Patna Conference on Incessant Ganga on Feb 25-26, 2017. This shows great vision and foresight on your behalf, to raise such crucial issues that is not only necessary for the Ganga, people of Bihar, environment of Bihar and future of Bihar, but also for the whole nation. We hope you will continue to lead the nation on this issue, and I am sure you will get huge support, including from me. Continue reading “Landmark Ganga Conference in Patna: What Bihar needs to urgently do”