The committee noted significant delays in addressing repairs and maintenance, even in the first year after commissioning, which accelerated the deterioration of the barrages.
Published Apr 28, 2025 | 11:24 AM ⚊ Updated Apr 28, 2025 | 11:24 AM
Medigadda Barrage (X)
Synopsis: Telangana Chief Minister A Revanth Reddy will discuss the NSDA report with officials and decide the course of action in rehabilitating Medigadda and two other barrages of the Kaleshwaram Lift Irrigation Scheme. The report has slammed the previous government for the faulty design of Medigadda. However, it did not spare the incumbent Congress regime either, lashing it for failing to act promptly on follow-up action after a disaster struck Medigadda.
The Telangana government is expected to finalise its course of action in rehabilitating Medigadda and two other barrages of the Kaleshwaram Lift Irrigation Scheme (KLIS) soon.
Chief Minister A Revanth Reddy will discuss with officials the final report of the National Dam Safety Authority (NDSA) and the way forward for restoring the three barrages in a day or two.
A couple of days ago, Irrigation Minister N Uttam Kumar Reddy said that at the next cabinet meeting, a decision would be taken on the report. Prior to that, it is learnt, the chief minister will have a review of the measures for the rehabilitation as suggested by the NDSA.
The report has slammed the previous government for the faulty design of the Medigadda Barrage — also known as the Lakshmi Barrage. However, it did not spare the incumbent Congress regime either, lashing it for failing to act promptly on follow-up action after the disaster struck Medigadda in October 2023, ahead of the Telangana Assembly elections.
The NDSA report has given enough firepower to the ruling party to target the BRS. Uttam Kumar Reddy said that the BRS leaders should hang their heads in shame for the faulty design of the barrage, which led to the collapse of the piers. He said: “The BRS is guilty. The ₹1 lakh crore project has collapsed under the weight of corruption.”
The BRS leaders shot back at the minister, saying that it was not NDSA’s report but that of the NDA, asserting that the entire report was politically motivated to tarnish the image of their party. BRS working president KTR said: “The report, which was ready by December 2024, was released just ahead of the party’s silver jubilee celebrations on 27 April, deliberately to discredit the party. It is NDA’s report and not an NDSA document,” he said.
The NDSA’s investigation has revealed alarming structural deficiencies in the Medigadda, Annaram, and Sundilla barrages, integral components of Telangana’s ambitious Kaleshwaram Lift Irrigation Project.
The findings, detailed in a recently released executive summary, highlight severe distress in the three cascading barrages on the Godavari River, raising critical concerns about their safety, resilience, and long-term viability.
The report calls for immediate stabilisation measures, comprehensive geotechnical studies, and a holistic rehabilitation design to address the debilitating damages and prevent potential catastrophic failures.
The report recommended immediate stabilisation measures to arrest ongoing distress, comprehensive geotechnical studies and advanced geophysical assessments to establish a reliable baseline for future interventions.
Hydraulic and structural designs, supported by appropriate model studies and mathematical modelling, are essential to ensure the long-term durability and safety of the barrages, the report pointed out.
The report stressed the importance of interdisciplinary collaboration among stakeholders, including the Irrigation and Command Area Development (CAD) Department, construction agencies and technical experts to ensure the project’s sustainability and resilience.
The NDSA report said that the Kaleshwaram Lift Irrigation Project, one of India’s largest irrigation initiatives, is designed to lift water from the Godavari River to irrigate millions of acres. Central to this project are the Medigadda, Annaram, and Sundilla barrages, which operate in a cascading system to lift water and finally transfer it to the Yellampally reservoir.
The barrages, approved by the Telangana government in March 2016, were constructed between 2016 and 2019, with contracts signed for their completion within 24 months. However, just a few years after their commissioning in 2019, all three structures have exhibited significant structural distress, prompting urgent scrutiny.
The NDSA began its investigation after receiving a request from the Secretary of the Telangana Irrigation Department on 13 February 2024. The NDSA, under the Dam Safety Act, 2021, constituted a high-level committee chaired by J Chandrashekhar Iyer, former Chairman of the Central Water Commission (CWC). The committee, comprising experts from CWC, NDSA, Central Soil and Materials Research Station (CSMRS), Central Water and Power Research Station (CWPRS), and Indian Institute of Technology (IIT) Delhi, conducted site inspections in March 2024, held 36 internal meetings, and reviewed extensive records, designs, and drawings to produce its findings.
The committee’s site inspections revealed severe structural issues across the Medigadda, Annaram, and Sundilla barrages. The Medigadda Barrage, the first in the series, has suffered the most pronounced damage. Block 7 of the barrage has experienced significant settlement, with piers cracking and tilting due to the formation of large cavities beneath the raft foundation.
This distress is attributed to piping — a phenomenon where soil particles are eroded by water flow, compromising the foundation’s stability. Additional damage includes the deterioration of energy dissipation structures, dislodgement of the wearing coat, and displacement of cement concrete blocks downstream.
The Annaram and Sundilla barrages have exhibited similar issues, including seepage, piping, and the dislodgement of downstream concrete blocks. These damages have raised serious concerns about the barrages’ ability to withstand operational and environmental stresses, particularly during the monsoon season. The committee noted that the observed distress patterns suggest systemic design and construction flaws that threaten the structural integrity of all three barrages.
In response to the alarming findings, the NDSA committee recommended a series of interim measures to be implemented before the 2024 monsoon season to ensure the safe passage of floods and mitigate further damage.
These measures, communicated to the Irrigation Department on 1 May 2024, included geotechnical and geophysical investigations and concrete condition assessments. While the department’s efforts helped manage flood passage and limit additional damage, the execution of the recommended studies was marred by significant shortcomings.
The committee criticised the present government for a lack of urgency and proper sequencing in the investigations, noting that premature grouting activities altered critical sub-surface geotechnical conditions. This irreversible change hampered the ability to accurately assess the original ground conditions and the state of the structures.
The use of geophysical tools like Ground Penetrating Radar (GPR), Electrical Resistivity Tomography (ERT), and Parallel Seismic tests identified anomalies, but the lack of follow-through with complementary drilling and verification limited the insights gained. The report underscores the need for strict adherence to investigative protocols before initiating corrective actions.
The committee’s analysis lashed the previous government, holding it responsible for several critical design and construction deficiencies. Hydraulic and structural design flaws, particularly in the energy dissipation mechanisms and structural components like end sills and rafts, have rendered the barrages ill-equipped to handle dynamic hydraulic forces and sediment loads.
The report said that the Gauge-Discharge curve, a fundamental design parameter, was neither verified nor confirmed by the project construction unit or the Central Designs Organisation (CDO) of the Irrigation and CAD Department, leading to misaligned design assumptions.
Model studies conducted by the Telangana State Engineering Research Laboratories (TSERL) failed to account for critical operational scenarios, such as the crack opening of a single gate at pond level, which could lead to sweep out hydraulic jumps and erosive pressures downstream. The studies also overlooked design inadequacies, including insufficient energy dissipation and improper radial gate seat positions, further exacerbating the barrages’ vulnerabilities.
Geotechnical investigations conducted during the design and construction phases were deemed inadequate, failing to identify the variability of the foundation strata and related uncertainties. The report highlights the absence of robust quality control measures, particularly in the construction of secant pile cutoffs, which are critical for ensuring the water-tightness of the foundation.
The lack of quality assurance compromised the structural integrity of the cutoff walls, contributing significantly to the observed failures.
The report said that the Medigadda Barrage serves as a stark example of the project’s challenges. The sinking of Block-7 is primarily attributed to piping caused by the transport of soil particles beneath the raft, forming large cavities.
The committee clarified that this piping is distinct from the sweep out of hydraulic jumps, as the spillway bays near the affected area were rarely used, a fact corroborated by Sentinel satellite imagery showing sediment accumulation downstream. The presence of holes in the upstream and downstream cutoff walls near piers 20-21 and 17, respectively, played a significant role in the piping formation.
NSDA underscored the lack of quality control during the construction of the secant pile cutoffs, describing it as a critical factor in the failure. Without proper procedures to ensure water-tightness, the cutoff walls were compromised, leading to the observed distress.
The committee also warned that undiscovered holes in the cutoff walls could pose a latent risk of future piping, necessitating thorough investigations of the remaining blocks of the Medigadda Barrage.
The Annaram and Sundilla barrages face similar challenges, with secant pile cutoffs not designed to handle the forces and moments transferred from their rigid connection to the raft. The combination of poor construction quality, inherent weaknesses in the RCC/PCC piles, and design deficiencies has created structural vulnerabilities at critical stress points.
Despite grouting efforts to prevent catastrophic failure, the vulnerabilities persist, with the potential for reoccurrence whenever the cutoff joints break.
The report warned that the entire length of both barrages is susceptible to similar distress under hydraulic load, stressing the urgent need to address these systemic issues. The absence of robust quality control and the direct connection of the cutoff walls to the raft are identified as the primary causes of the observed damages.
The report said that the Operation and Maintenance (O&M) challenges have further compounded the structural issues. The committee noted significant delays in addressing repairs and maintenance, even in the first year after commissioning, which accelerated the deterioration of the barrages.
The absence of an O&M Manual and non-compliance with the provisions of the Dam Safety Act, 2021, have led to sub-optimal management of the structures.
(Edited by Muhammed Fazil.)
