Fears over safety of Polavaram Dam has once again caused worry due to quality defect, as the upper coffer dam has collapsed once again. Officials said that it has collapsed at a width of about 10 feet and a depth of 8 feet. The coffer dam was damaged in a similar way in 2022. Earlier, a crucial diaphragm wall related to the project was washed away.
However, it is noteworthy that neither the central government nor the NDSA has yet spoken out about the quality of the project. In fact, although Polavaram is a central government project, it is not being built on its own. While the state government is carrying out the construction work, the center is providing financial assistance.
The AP government has taken up the Polavaram project with a water storage capacity of about 194 TMC. As part of the construction plan, coffer dams are to be constructed upstream and downstream to divert the flow of Godavari. After that, the main dam and diaphragm wall will have to be constructed.
In this context, plans were initially made to build an upper cofferdam with a length of 2.1 km and a height of 31 meters to prevent the flood flow of 28 lakh cusecs. Later, its height was increased to 41.5 meters. However, the upper cofferdam was built haphazardly. In the 2.1 km long dam, a gap of 380 meters was left at one place and 300 meters at another.
The diaphragm wall was damaged at 3 places due to the heavy Godavari floods in 2020. At one place, 200 meters of the wall was washed away. At many places, the diaphragm wall was eroded by sand and ravines were formed. The accident occurred due to not building a cofferdam at the top. The damage to the diaphragm wall caused a loss of about Rs. 500 crore. ECRF works were completely stopped.
As a result, the construction cost of the project increased from Rs. 35,000 crores to Rs. 55,000 crores. After that, the cofferdam was further increased in height. It is reported that the cofferdam has been damaged in the same area where it was damaged in the past due to poor quality. As a result, the safety of the Polavaram Dam has become questionable.
