The Comptroller and Auditor General (CAG) has concluded that about 65.8 thousand million cubic feet (tmc ft) [equal to about 70% of the capacity of the Mettur reservoir] could not be harnessed in three irrigation structures due to the “delay in sanction of works” on removal of sedimentation.
This was stated in a report of the CAG’s performance audit of outcomes in surface irrigation with respect to works executed in Amaravathy and Kelavarapalli reservoirs (falling under the Krishnagiri sub-basin) and Radhapuram channel (Hanumanadhi sub-basin) under the Tamil Nadu Irrigated Agriculture Modernization and Water Bodies Restoration and Management (TN IAMWARM) programme for the year ending in March 2020, which was placed on the floor of the Assembly on Wednesday.
The CAG said the “absence of periodical capacity surveys” by the Water Resources Department led to “non-ensuring adequate silt storage and retardation of sedimentation” in the irrigation structures. Increased conveyance efficiency for the Amaravathi reservoir and the Radhapuram channel was only partially achieved. With respect to Amaravathi, nearly ₹75 crore was spent towards channel rehabilitation works. As for Kelavarapalli, the conversion of gap area into fully irrigated area remained unachieved and there was “substantial reduction.”
Suggestions given
The CAG recommended that periodical capacity surveys be held to assess the extent of sedimentation. It asked to prioritise sanction of the works on removal of sedimentation, formulate and update the rules for regulation of water for irrigation systems. It suggested that the development of integrated water resources management system be completed promptly and efforts be made to bridge the gap between the irrigation potential and actual realisation.
