Early warning of disasters can save lives

In India, these days there exists a sophisticated early warning system run by the IMD that warns about impending cyclones in the cyclone prone Bay of Bengal, saving countless lives by timely evacuation of people. In September 1893, a massive rockfall completely blocked the Birahi Ganga River valley, in the Indian Himalayas, constructing a natural landslide dam that stood over 900 feet high. This created a large, deep body of water called Gohna Lake. Although a massive portion of the dam initially broke in 1894—destroying towns downstream like Srinagar—the lake was not entirely empty and remained a prominent feature for decades. During the severe Himalayan floods of 1924, the remaining landslide dam breached for a second time, unleashing another devastating wave down the Alaknanda valley. However, despite these catastrophic events taking place in highly fragile mountainous regions, in both 1894 and 1924 no lives were lost due to an early warning system being in place, even back then. In the context of the landslide and horrific floods in Nepal questions are being raised if some early warning system could have been in place. In one case where headmaster Rajendra Dawadi of Tribhuvan Trishuli School, perhaps got a few minutes' early warning, he rang the bell, turned buses back and was able to save 1,643 lives of children. In India, these days there exists a sophisticated early warning system run by the Indian Meteorological Department that warns about impending cyclones in the cyclone prone Bay of Bengal, saving countless lives by timely evacuation of people. An excellent example of international cooperation in this field is the Indian Ocean Tsunami Warning and Mitigation System (IOTWMS) that provides real-time alerts and threat assessments to countries in the Indian Ocean Rim to save lives from destructive tsunamis. It was created after the deadly December 2004 Indian Ocean earthquake and tsunami that killed almost 250,000 people, mostly in Aceh province of Indonesia. Operations rely on three designated national centres—Australia ( JATWC), India (ITEWC), and Indonesia (InaTEWS)—which monitor seismic and sea-level activity round the clock. Land-based seismographs and seismic stations detect undersea earthquakes and measure their magnitude within minutes. Seafloor bottom pressure recorders detect pressure changes from passing tsunami waves and transmit data via satellite to warning centres. Coastal tide gauges monitor sea-level changes in real-time to verify whether a tsunami wave has formed. Regional Tsunami Service Providers (TSPs) process this data and issue risk assessments to national warning centres, which then alert local populations. Disasters do happen, but it is an early warning that can save lives. The early warning system installed by the British in 1894 at Lake Gohna even worked for the 1924 lake breach. In 1894, faced with a massive 900-foot natural landslide dam that they knew would eventually overtop, Lt. Col Pulford, Lt. Col Crookshank, and geologist Thomas Holland engineered what is widely considered one of the first successful modern early warning systems in the world. The system relied on a highly coordinated mix of latest technology for the era i.e. telegraph and strict infrastructural preparation. What they did was nothing short of a miracle. They established a dedicated temporary telegraph line running directly from the remote monitoring outpost at Durmi village (near the lake) down to the district headquarters in Chamoli. Engineers stationed at the dam recorded the lake's water levels and structural behaviours continuously. Daily progress reports were telegraphed down the valley so authorities could track exactly how fast the lake was filling up. Ahead of the breach, authorities established a series of observation posts along the entire lengths of the Alaknanda and Ganga valleys. Physical 'danger levels' were clearly marked on rocks and posts near downstream settlements. If local watchmen saw the river cross these lines, they had explicit orders to sound immediate local alarms and initiate pre-planned evacuations. Rather than waiting for a sudden failure, Crookshank and Holland studied the geomorphology of the debris to map out a timeline. On August 22, 1894, Crookshank telegraphed a warning that the dam would fail within 48 hours. They were incredibly accurate—the lake overtopped just past midnight on August 25. Because of the precise timeline, every single vulnerable village, including the major town of Srinagar, was completely evacuated before the wall of water arrived. Knowing the immense kinetic energy a flash flood holds, the authorities did not just move people; they dismantled suspension bridges in the expected path of the flood to prevent the iron and cables from being turned into destructive battering rams downstream. Major pilgrim routes winding through the Himalayas were entirely diverted to higher ground to ensure travellers were not caught in the valley floors. Thanks to this meticulous system, when 10 billion cubic feet of water were violently released in less than six hours during the 1894 burst, the entire valley was swept clean—yet virtually no lives were lost. This exact blueprint of observation posts and valley-wide telegraph communication remained the foundational network that allowed authorities to quickly spread warnings further downstream when the lake suffered its second massive breach during the monsoons of 1924. Satisfyingly, the IOTWMS is fully functional and operational. It is continuously tracking seismic activity across the entire ocean basin. The designated TSPs in Australia, India, and Indonesia actively monitor undersea earthquakes and routinely issue automated, public data bulletins. The framework is regularly stresstested through basin-wide simulations. The comprehensive Exercise Indian Ocean Wave 2025 (IOWave25) successfully tested the end-to-end warning chain—from sensor detection to community evacuations—involving over 320,000 participants across multiple countries, including India, Indonesia, Sri Lanka, Timor-Leste, and the UAE. In 2004, the region had zero realtime basin infrastructure. Today, the system creates computerized impact forecasts within 10 to 30 minutes of a major earthquake, giving vulnerable coastal zones vital time to react. While the primary detection grid is highly functional, the system faces two ongoing operational hurdles. Firstly, while warning centres receive the data instantly, some countries still struggle to rapidly transmit the alert to remote, isolated coastal villages via local sirens or mobile texts. Secondly, if an earthquake strikes right next to a coastline, the resulting tsunami waves can hit land in less than 5 to 10 minutes. In these scenarios, even the fastest automated satellite network does not replace human education, which teaches people to instantly move to high ground the moment they feel the earth shake. One can only wish that some kind of an early warning mechanism existed between authorities of China and Nepal. The hope is that this disaster will lead to the establishment of one. Sandeep Chakravorty is Ambassador of India to Indonesia.