Water Commission to study sedimentation level at 40 major reservoirs to assess change in storage capacity and life expectancy

Vijay Mohan

Chandigarh, May 1

The Central Water Commission (CWC) will undertake studies to assess the level of sedimentation at 40 major reservoirs across the country to determine the change in their storage capacity as well as their life expectancy.

Microwave satellite data would be used to update the elevation, area and storage capacity of the reservoirs and estimate the live storage loss due to sedimentation, and prepare revised maps and data sheets.

“We are inviting proposals from agencies having the requisite technical expertise and experience to evaluate satellite data,” a CWC official said.

“The proposals are expected to be shortlisted later this month for final selection,” he added.

Sedimentation is the process where loose soil, silt, rock and debris flow in with the water that enters reservoirs and deposit on the bed. The level of sedimentation depends upon the terrain, geology and environmental conditions of the area through which the feeding rivers and tributaries flow. It is unavoidable and over a period of time, reduces the storage capacity of the reservoirs.

Large-scale deforestation, unscientific agricultural practices, industrial processes and anthropogenic activities in catchment areas also increase the silt load in rivers and aggravate sedimentation, raising environmental concerns.

CWC has already carried out 21 sedimentation studies at various reservoirs through microwave data.

According to CWC officials, efficient reservoir management requires that the dynamic aspects such as water spread and sediment distribution are monitored and mapped periodically as sedimentation has a direct bearing on the capacity and life of reservoirs.

There are 124 major reservoirs in the country that require monitoring.