Kerala’s submission to the Central Comprehensive Evaluation Expert Committee on the Mullaperiyar dam has shifted attention from the physical condition of the 130-year-old structure to a deeper institutional question: whether the dam’s safety is being assessed through a consistent and sufficiently rigorous technical framework. The state has asked for an independent, technically comprehensive safety examination, arguing that earlier assessments contain significant differences and that the existing rule curve does not adequately account for the 2018 flood.
The submission followed a two-day inspection of the dam by the expert committee, led by Balraj Joshi, on September 1 and 2. The committee examined the structure, its strength, seepage, foundation pressure, rock and soil stability, maximum flood levels, water-release systems, monitoring instruments, sediment accumulation, storage capacity and emergency preparedness. Its inspection report has not yet been released.
That gap between an inspection taking place and its findings becoming public is central to understanding the current stage of the dispute. The available report establishes that a wide range of technical parameters was examined, but it does not establish what the committee concluded about any of them. Kerala’s submission is therefore a position presented to the committee, not the final technical determination of the dam’s condition.
This distinction matters because Mullaperiyar is not being discussed only as an old piece of infrastructure. It is a live water-management system whose safety assessment involves structural engineering, hydrology, flood estimation, instrumentation, reservoir operations and emergency planning. A conclusion about one part of the system cannot automatically settle the others. A dam may be assessed through its structural stability, but its operating risk also depends on how water levels, inflows, spillways and emergency procedures are understood and managed.
The scope of the recent inspection reflects that complexity. According to the report, the committee’s technical officials looked at the dam’s structural condition and foundation, but also at seepage, sedimentation, reservoir capacity, monitoring equipment and emergency readiness. These are different components of the same safety chain. If monitoring instruments do not provide reliable information, or if the assumptions used for flood discharge are disputed, the question is not limited to the concrete or masonry structure itself. It extends to the information and administrative systems used to operate the reservoir.
Kerala’s submission says that no complete technical inspection has been conducted at the dam since 2011. It also says that differences exist between a recent study by IIT Roorkee and an assessment by the Central Water Commission. In addition, the state has pointed to significant variations among assessments carried out by the Central Water Commission at different times. These claims, as reported by Dinamalar, have not been independently tested in the supplied material. They nevertheless identify the central evidence problem: when technical agencies produce differing assessments, the public needs to know which methods, measurements and assumptions produced those differences.
A technical disagreement is not necessarily evidence that one assessment is correct and another is flawed. Different studies may examine different questions, use different data periods or apply different safety criteria. But such differences become consequential when they influence the maximum permissible reservoir level or the operation of release systems. The expert committee’s eventual report will therefore be important not merely because it may describe the dam’s condition, but because it may clarify the basis on which safety decisions are made.
The dispute over the rule curve illustrates this problem. A rule curve sets permitted reservoir levels for different periods of the year. Kerala’s submission says the curve was determined using the water levels allowed in the reservoir during different parts of the year, but that it did not adequately take the 2018 flood into account. On that basis, the state has argued that the maximum level of 142 feet under the rule curve is not acceptable and that the maximum permitted level should be reduced.
The submission does not, by itself, establish that the 142-foot level is unsafe. It establishes that Kerala is challenging the technical basis for that level and asking the committee to reconsider it. The unresolved issue is therefore not simply whether the reservoir should hold more or less water. It is how the maximum level was calculated, what flood conditions were included, what discharge capacity was assumed, and whether the operating rule remains appropriate in light of the evidence considered by the authorities.
The reference to the 2018 flood also shows why historical operating rules can become contested. A rule curve is not only an engineering diagram; it is an administrative decision based on assumptions about rainfall, inflows, storage and the ability to release water. If a significant flood event exposes conditions that were not adequately represented in the original assessment, authorities may face pressure to revisit those assumptions. Whether that happened in this case, and what technical changes would follow, can only be established through the expert committee’s findings and the underlying data.
The institutional architecture is equally significant. The recent inspection was conducted by a central expert committee, while the submission came from the Kerala government. The report also refers to assessments by IIT Roorkee and the Central Water Commission. This means that the safety debate is being shaped by multiple institutions with different roles: an expert committee conducting an evaluation, a state government presenting concerns, an academic institution associated with a technical study and a central water authority whose assessments are being compared.
For readers, the important question is not which institution is mentioned most prominently, but how their findings will be reconciled. A credible public record would need to distinguish between inspection observations, technical measurements, modelling assumptions, operational recommendations and final decisions. It would also need to explain why assessments differ where they do. Without that clarity, the publication of multiple reports can increase uncertainty rather than resolve it.
The inspection’s inclusion of emergency preparedness is particularly relevant to the governance of large water infrastructure. Dam safety is not confined to routine conditions. It also involves the systems used when water levels rise rapidly or when a monitored parameter changes unexpectedly. The supplied report does not provide details of the emergency plan or assess its adequacy. It only states that emergency preparedness was among the areas examined. The committee’s report will need to show what was reviewed and whether any changes were proposed.
The same caution applies to sediment accumulation and storage capacity. The report says these were inspected, but it does not provide measurements or conclusions. Sedimentation can affect the usable capacity of a reservoir, while the stated storage capacity is relevant to water-level management. However, no inference about the present capacity or operational risk can be made from the supplied material alone. Those questions require the inspection data and the committee’s technical interpretation.
The broader urban and regional lesson is that infrastructure safety depends on more than periodic physical inspections. It depends on the continuity of records, the comparability of technical studies, the quality of monitoring instruments and the transparency of decisions that affect people living downstream or relying on the reservoir. The Mullaperiyar case, as presented in the report, brings all of these elements together without yet resolving them.
It also demonstrates why ageing infrastructure requires an institutional process that is both technically rigorous and publicly intelligible. The dam’s age is cited in the Kerala submission as a reason for an independent and stringent safety examination. Age alone does not determine present safety, but it increases the importance of reliable inspection histories, consistent methods and clear maintenance and operating records. The supplied report does not state whether those records are complete or whether the committee found deficiencies.
The next decisive document is the expert committee’s inspection report. Until it is released, the public record contains Kerala’s request for a fresh and independent technical examination, its objections concerning assessments after 2011, its comparison of IIT Roorkee and Central Water Commission findings, and its challenge to the 142-foot maximum under the rule curve. These are substantial issues, but they remain claims and recommendations contained in a state submission rather than final findings.
What the current episode confirms is that the Mullaperiyar debate has moved beyond a single question about reservoir height. It now includes the quality of technical evidence, the treatment of flood events, the consistency of institutional assessments and the preparedness of the operating system. What remains uncertain is how the expert committee will assess those issues and whether its report will provide a common technical basis for future decisions.
