After the sinking of six piers of the Medigadda Lakshmi Barrage – the starting point of the BRS government’s prestigious Kaleshwaram Lift Irrigation Project (KLIP) – a six-member team headed by National Dam Safety Authority (NDSA) Chairman Anil Jain visited the site on October 24 to inspect the damage. The committee’s report, which has now been made public, says the piers had sunk due to a combination of issues involving “planning, design, quality control and operation and maintenance (O&M).” While the barrage has eight blocks, piers 16 to 21 of the seventh block were damaged.
“The distress condition developed in one block of the Medigadda barrage is adversely affecting the functionality of the barrage. The barrage under the present condition is rendered useless until fully rehabilitated,” the report said. It further said that the damaged block seven may have to be structurally restored to make it functional, and considering the commonalities, it was possible for other blocks to also witness similar damage. “This would warrant rehabilitating the whole barrage. Filling the reservoir in the present condition would worsen the barrage's health and should not be resorted to,” the committee said.
The report dated November 1, was addressed to Rajat Kumar, Telangana Special Chief Secretary for Irrigation. Listing its broad findings based on the team’s inspection of the barrage site inspection, discussions with stakeholders and the Irrigation Department’s documents, the committee said the main reason for the damage was the “settlement of the barrage raft.” The piers, which form a monolith with the raft, have also settled, moved and cracked, the committee noted, listing many possible reasons such as the inadequate bearing capacity of the foundation material (sand), "transportation" of the foundation material, and the failure of support systems for the foundation upstream due to the barrage load.
“There appears to be construction deficiency due to a lack of stringent quality control” during the construction of certain structures, leading to the failure, it said. The committee also flagged “deficiencies in the project planning and design.” “The barrage has been designed as a floating structure but constructed as a rigid structure,” it said.
The report also flagged that the dam owners have not inspected or maintained certain structures – the cement concrete blocks or launching aprons – since the commissioning of the barrage in 2019-20. “This maintenance deficiency of the dam owners has progressively weakened the barrage, leading to its failure. This is a significant lapse on the operation and maintenance front,” the report said.
It also flagged that pre and post-monsoon inspections and various other data sought by the team were not provided by the Irrigation Department, and said this suggested that inspections weren’t carried out despite regular reminders from NDSA. “This is a significant omission, thus attracting provisions of section 41 (b) of chapter X of the Dam Safety Act 2021 (refusal to comply with direction given by the National Committee or Authority)… This is a serious matter as the barrage has a high-risk potential for life and the economy,” the committee’s report said.
The two barrages constructed upstream of Medigadda under the Kaleshwaram project – Annaram and Sundilla barrages – have similar designs and construction methodologies, which makes them prone to similar damage, the committee said. “Signs of boiling already exist downstream of Annaram barrage, a precursor to failure. These barrages also should be examined urgently for signs of piping/ distress,” it said. On November 1, water seepage was reported from two gates of the Annaram (Saraswati) barrage in Mahadevpur mandal of the Jayashankar Bhupalpally district.