The Central Electricity Authority (CEA) released a comprehensive report in May 2025 detailing the failure of Extra High Voltage (EHV) transmission line towers across India during the period from January to December 2024. The Standing Committee of Experts, formed under the Electricity Act, 2003, is responsible for investigating these incidents and recommending corrective actions to prevent future occurrences.
A total of 76 EHV transmission line towers collapsed across 28 different transmission lines of 220 kV, 400 kV, and 765 kV categories. Out of these, 68 were Suspension Type Towers and 8 were Tension Type Towers. Most of the failures occurred in towers designed for Wind Zone 2 and 4, highlighting the need to reassess existing wind zone classifications and update design parameters accordingly.
The committee noted that timely reporting by utilities remains a challenge. Of the 12 utilities that reported failures, only 4—PGCIL, ADANI, DVC, and RVPN—intimated the failures within the mandatory 48-hour timeframe. Detailed reports were submitted within a month for only 14 of the 28 affected lines. One utility, APTRANSCO, failed to submit a detailed report even after a reminder letter from CEA.
Power Grid Corporation of India Limited (PGCIL) reported multiple failures. A notable case involved the 400 kV D/C Kishenpur-New Wanpoh line, where tower collapses were attributed to land sliding. Similar incidents were previously reported in 2020 and 2021 but recommended geological investigations and reinforcement measures had not been implemented. Another PGCIL tower failure on the 400 kV Silchar-Imphal line was linked to sabotage, where an IED was used to damage the tower legs.
Adani’s 765 kV Bilaspur–Rajnandgaon and Akola–Ektuni transmission lines each experienced failure of four suspension towers. The cause was identified as heavy whirlwinds and localized cyclonic storms, likely exceeding design wind speeds. In both cases, the towers had been designed as per IS 802:1995, and the committee recommended upgrades to the newer IS 802:2015 standards.
RVPN reported five tower failures on the Bhadla–Jodhpur–Merta line due to windstorms and lightning, and two on the 220 kV MIA-BTPS line due to theft-related conductor cutting. The latter line, nearly 50 years old and inactive since 2020, is being considered for dismantling.
Other incidents included collapses caused by cyclonic storms (MSPCL’s Imphal–Thoubal line), theft and wind impact (MPPTCL’s Rewa lines), and foundation issues from flash floods (PGCIL’s Gwalior–Agra line). DVC’s lines in Jharkhand suffered from high wind tunnel effects and reported successful restoration using drone inspections and modern methods.
The committee stressed the importance of obtaining accurate wind speed data to verify whether conditions exceeded design thresholds. Utilities were urged to use IMD’s network of over 700 wind sensors and also coordinate with local airports and weather stations.
Key recommendations include timely reporting of failures, usage of pile foundations in flood-prone areas, adoption of IS 802:2015 standards for all restored towers, improved patrolling in theft-prone areas, and digitized inventory management. Utilities were also advised to conduct routine maintenance and coordinate with dam authorities in regions prone to flash flooding.
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