The calamity, which unfolded just as the northeast monsoon began on 16 October, underscores a stark reality: Cloudbursts striking when reservoirs are full pose an existential threat to lives and livelihoods in vulnerable regions like Kerala.
Published Oct 22, 2025 | 8:43 AM ⚊ Updated Oct 22, 2025 | 8:43 AM
A vehicle washed away following the heavy rains in Idukki.
Synopsis: On 19 October, relentless overnight rain unleashed chaos across the Idukki district of Kerala. The tragedy serves as a clarion call for urgent policy reform in disaster management. Early warning systems must evolve to be people-centric and multi-hazard oriented.
The intensifying northeast monsoon claimed its first life in Kerala’s Idukki district on 19 October, as relentless overnight rain unleashed chaos across the region. Torrential downpours inundated roads and homes, swept away parked vehicles and triggered devastating mudslides, bringing traffic to a standstill while crippling power lines and mobile networks.
Neighbouring Tamil Nadu’s Theni district also bore the brunt, with mudslides disrupting the Kumali inter-state ghat road. Villages along the Periyar River faced severe flooding as surplus water was released from the Mullaperiyar Dam. The water level reached 139.35 feet by the evening of 19 October, with an inflow of approximately 5,516 cusecs and an outflow of 1,349 cusecs. Earlier that day, inflows had surged to 40,733 cusecs, prompting authorities to open all 13 shutters.
Worst-hit areas in Idukki’s Kumily panchayat, including Onnam mile, Attapallam, Kumily town, Periyar Colony, Chelimala, Valiyakandan, and Anavachal, reported widespread inundation, forcing residents to flee to upper floors or relatives’ homes.
The deluge extended beyond Idukki, disrupting traffic on the Gudaloor-Kozhikode road in Malappuram district due to rising waters in the Karakodam, Kalakkad and Athithode rivers. Meanwhile, even urban Kochi witnessed minor flooding, inconveniencing commuters.
This calamity, unfolding just as the northeast monsoon began on 16 October, following the withdrawal of the southwest monsoon, underscores a stark reality: Cloudbursts striking when reservoirs are full pose an existential threat to lives and livelihoods in vulnerable regions like Kerala.
Yet, the tragedy in Idukki is far from an isolated event. It serves as a clarion call for urgent policy reform in disaster management. As climate change intensifies monsoon extremes, the confluence of heavy rainfall and high reservoir levels amplifies risk, potentially triggering cascading disasters such as dam breaches, flash floods, and landslides.
India must, therefore, prioritise disaster preparedness, robust early warning systems and proactive reservoir management to mitigate such threats. Failure to act invites repeated catastrophe, as Kerala’s flood-prone history repeatedly demonstrates. The government must leverage data and lessons from past events to build resilience, ensuring human lives are not sacrificed to inertia or interstate disputes.
Consider the immediate context of the October 2025 havoc. The India Meteorological Department (IMD) had issued an orange alert for six districts, including Idukki, Malappuram, Kozhikode, Wayanad, Kannur and Kasaragod, warning of heavy to very heavy rainfall. Yet the intensity caught many off guard, with cloudburst-like conditions dumping over 100 mm of rain in a few hours, leading to flash floods and landslides.
The Mullaperiyar dam, a 129-year-old structure under Tamil Nadu’s control but located in Kerala, exemplifies the peril. Its full reservoir level is 142 feet, and with water nearing 140 feet amid surging inflows, releases into the Periyar river exacerbated downstream flooding.
Nearby, the Idukki reservoir stood at 2,381.92 feet on 18 October, representing 75.8 percent of capacity, further straining the region’s hydrological balance. Such scenarios illustrate how reservoirs, designed primarily for irrigation and power, become ticking time bombs during extreme monsoon events if not managed with foresight.
Kerala’s flood history offers stark warnings. The 2018 deluge, the worst in a century, claimed 483 lives, evacuated over 10 lakh people, and caused damages estimated at ₹31,000 crore ($4.3 billion). Triggered by rainfall 40 percent above normal in August alone, it affected all 14 districts, with landslides burying entire villages.
In 2019, another episode killed 121 people, displaced over 2,00,000, and inflicted economic losses exceeding ₹10,000 crore. These floods were linked to mesoscale cloudbursts, with rainfall exceeding 50 mm in two hours across multiple sites, amplified by warm sea surface temperatures.
In 2021, floods and landslides claimed 42 lives and caused damage of over $25 million, primarily in southern districts such as Kottayam and Idukki.
Collectively, these recurrent disasters from 2018 to 2021 resulted in over 1,000 deaths and billions in losses, disproportionately affecting hilly terrains where deforestation and quarrying exacerbate vulnerability.
Climate change acts as a potent accelerant, reshaping Kerala’s monsoons into more volatile extremes. Studies indicate rainfall surges in early August 2020 contributed to landslides like Pettimudi in Idukki, which killed 70 tea estate workers.
Monsoon onset in Kerala has varied significantly over the past two decades, arriving early in over half of the years, producing erratic patterns. Extreme precipitation events, including cloudbursts, have surged, with deep convective clouds and heavy rainfall intensifying from 2000 to 2020 during summer monsoons.
Synchronous extreme rains in Kerala have displayed circular movements, worsening floods, as witnessed in 2018 and 2019. Nationally, India remains highly vulnerable to hydro-meteorological extremes, with climate models predicting more intense monsoons due to warmer oceans and atmospheric instability.
Yet the absence of comprehensive cloudburst data hampers precise forecasting, a challenge scientists attribute to climate change and anthropogenic activities like urbanisation. These shifts necessitate integrating climate projections into disaster preparedness and public policy frameworks.
India’s disaster management architecture, anchored by the National Disaster Management Authority (NDMA) established under the 2005 Disaster Management Act, provides a structural foundation but suffers from gaps in execution.
While NDMA lays down policies for prevention, mitigation, and preparedness, implementation deficits persist, particularly in monsoon-prone states. IMD forecasts and warnings often fail to reach last-mile communities in real time.
Though the Standard Operating Procedure emphasises early warning as a cornerstone of risk management, including hazard forecasts, vulnerability assessments, and rapid communication, the October 2025 cloudburst revealed deficiencies in impact-based forecasting.
Early warning systems (EWS) must evolve to be people-centric and multi-hazard oriented. India’s push for a Common Alerting Protocol (CAP)-based Integrated Alert System, envisioned by NDMA to disseminate warnings via SMS, apps and sirens, remains unevenly implemented.
Impact-based forecasting, which predicts not just rainfall but consequences like flood extents, offers promise for regions like Idukki. Yet, as of May 2025, training sessions by the National Institute of Disaster Management underscored the need for accurate data and community-level preparedness to make EWS effective.
In the Western Ghats, calls for reforms in disaster governance emphasise strengthening post-disaster assessments and financial support. Kerala’s 2018 floods prompted a post-disaster needs assessment, but recommendations, such as zoning restrictions in floodplains, have been sluggishly implemented.
Monsoon management, especially reservoir operations, requires interstate coordination and scientific protocols. The Mullaperiyar dam’s contentious status, with Kerala demanding decommissioning due to seismic risks and Tamil Nadu prioritising water security, exemplifies policy paralysis.
Rules mandate gradual releases to prevent sudden surges, yet October 2025 outflows exceeding 8,000 cusecs overwhelmed downstream areas. Policy must enforce real-time monitoring, integrate AI-driven predictive inflow models, and strengthen dam surveillance.
Broader strategies include afforestation to reduce landslide risks, as deforestation in Idukki exacerbates soil erosion. Community drills, as advocated by NDMA, could save lives, yet rural Idukki lacks sufficient evacuation infrastructure.
Disaster preparedness also extends to health and economic resilience. Floods amplify monsoon-related illnesses, demanding preventive action like avoiding contaminated water.
Economically, insurance penetration in Kerala remains low, leaving farmers and small businesses vulnerable. Policy interventions should mandate flood-resilient building codes and invest in green infrastructure, including permeable pavements in urban areas such as Kochi.
The Idukki deluge of October 2025, with its deadly combination of cloudbursts and reservoir overflows, is a harbinger of worsening extremes unless India overhauls its public policy approach.
Climate change is already fueling more frequent and severe monsoons, evidenced by a 20-year trend of intensifying precipitation and catastrophic floods.
Policymakers must act decisively: strengthen NDMA’s mandate with enforceable EWS, foster interstate cooperation on dams like Mullaperiyar, and embed climate resilience into development plans.
The cost of inaction is measured in lives: Over 700 fatalities in Kerala’s floods since 2018 alone. This is a moment to transition from reactive to proactive policy, ensuring that the next monsoon does not claim more innocent victims.
Only through such reforms can India safeguard its citizens against the gathering storms.
(Views are personal. Edited by Muhammed Fazil.)
