IWRM can reduce floods in downstream areas of hydel dams:

For mitigating floods in the downstream areas of hydel dams in the North East region, a river science expert has suggested adoption of an Integrated Water Resources Management(IWRM) approach in the area.

River science expert and former IIT-Roorkee Professor Nayan Sharma suggested that the existing or planned hydel dams of NEEPCO, Assam Power General Corporation (APGCL) and NHPC be overhauled to incorporate necessary flood cushion in the reservoir along with evolving optimal reservoir operation rule curves.

IWRM is a Water Resources Planning process which "promotes the coordinated development and management of water, land and related resources in order to maximise the resultant economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystems", Sharma told PTI.

He suggested using recent advance technology for mitigation of the flood devastations wrecked in downstream areas of hydel dams.

The recent advance technologies include Piano Key Weir (PKW) for achieving enhanced discharging capacity and increased reservoir storage, river restoration scheme for maintaining required channel flood conveyance capacity, he said.

It also include comprehensive Catchment Area Treatment programme in the watershed areas for controlling sediment ingress to the reservoir, scientifically overhauling reservoir operation schedules.

"Implementation of the suggested solutions will turn around these mono-purpose run-of-the-river hydel projects into multi-purpose projects which will be able to accrue multiple benefits for flood moderation, stable river restoration and sustaining ecology, besides generating cheaper and eco-friendly clean hydro power," he said.

Sharma who is also associated with the Assam Water Resources department suggested that planners and policy makers consider adoption of the IWRM approach to derive optimal benefits for society by using the limited natural and investible resources in a sustainable manner.

"Ranganadi, Doyang, Kopili, Karbi Langpi and Umiam hydel dams in the North East are all operated on a single purpose mode devoid of any reservoir storage space for flood cushion to hold back flood flows, and thus regularly wreck havocs on the downstream crippling the lives of the people there," he said.