Real-time structural health check for TN dams

Under the World Bank-funded Dam Rehabilitation and Improvement Project (DRIP), the Central Water Commission (CWC) had proposed to install hydro-meteorological, geodetic, geotechnical and seismic instruments in dams, as instrumentation plays a vital role in ensuring their safety.

It had also proposed to automate the process of data acquisition, processing, analysis and interpretation, which would help in taking timely and appropriate remedial action, said a senior Tangedco official.

The objective of optimum dam instrumentation is to select the most sensitive parameters that will change significantly before any failure, and monitor the behaviour of dams in these parameters precisely to develop the rehabilitation measures or to plan the effective risk management strategy. The instruments are classified as those required for the dam body and that for reservoir and catchment area.

The parameters monitored for the dam body are temperature of concrete, pore water pressure, up-lift pressure, seepage, opening/closing of contraction joints to changes that take place in climatic conditions, rainwater, reservoir water and dam catchment area. The data thus collected from various locations in the dam 24x7 would be transmitted to the local data centre and from there to the main data control room at the Tangedco headquarters.

As part of the ongoing DRIP, the Emergency Action Plan (EAP) is being prepared for 89 dams, of which 69 are operated by the Water Resources Department and 20 by Tangedco. The purpose of EAP is to identify emergency situations that could threaten dam, and to plan an expeditious and effective response.