Himalayan tragedy: A disaster in Nepal, a warning for India
The disaster in Nepal is a stark reminder that natural hazards do not respect political borders. What begins as a catastrophe in a remote mountain valley can threaten lives and infrastructure in India. India and Nepal need to move from flood warnings to real-time, basin-wide impact forecasting and coordinated risk management
A catastrophic flash flood hit Nepal's Himalayan border area on August 26, killing people and causing massive destruction. Houses have been inundated; roads and bridges have been destroyed or washed away, and infrastructure like electricity have been affected. Rescue efforts are ongoing in inaccessible locations; meanwhile, it is still unclear how much damage the mega disaster has caused. However, this is not just Nepal's problem, but India's, especially Bihar and eastern Uttar Pradesh's. The reason is obvious: rivers carrying Himalayan waters do not recognise political boundaries.
So far, the exact reason for the flash flood is being investigated. According to initial findings, an ice-rock or glacial avalanche could have occurred, possibly along with a temporary river blockade and sudden releasing of huge amount of water, rock, and sediments. An earthquake is also one of the reasons. The idea of glacial lake outburst has so far not got enough evidence.
What should be remembered in general is that flash flood in the Himalayas is the ultimate result of a chain of events starting with glacier or slope instability, followed by river blockade and huge release of water, rocks, and sediments. The Himalayas are gradually turning into the sources of cascading disasters.
The present flooding started from the upper parts of Bhotekoshi/Lhende river system at the border between Tibet and Nepal. The flood wave travelled from the Bhote Koshi and Trishuli river systems to the Narayani and further down the river as the Gandak in India. This explains why there has been fear for the downstream areas of Uttar Pradesh and Bihar.
When the Rivers of Nepal Flow into India
To appreciate India's vulnerability, one needs to move away from the political map and consider the river-basin map. While politically Nepal and India are two separate countries, hydrologically they are one system. Himalayan water feeds the irrigation, domestic and ecological needs as well as livelihoods of millions, but if anything goes wrong in the upper basins, these very rivers can be transformed into destructive rivers.
Sarda, Ghaghra, Rapti, Gandak, Burhi Gandak, Bagmati, Kamla and Kosi are some of the rivers contributing to floods in Uttar Pradesh and Bihar that originate in or travel through Nepal. India and Nepal already have bilateral agreements concerning flood forecasting and water management. The present disaster is a good opportunity for strengthening them.
Gandak is particularly relevant to the present situation. Narayani River becomes Gandak when it enters India and travels through Uttar Pradesh and Bihar and finally meets the Ganges River. Bihar is also vulnerable to other Himalayan rivers such as Kosi, Bagmati, Burhi Gandak and Ghaghra.
An unexpected outburst after an avalanche, landslide, or flooding of a river due to the formation of a dam would give very little warning time. Hence, the early warning system should not only alert about the crossing of river levels by a river. It should also warn about which villages can be flooded, what infrastructure would be affected and where the search and rescue teams and aid materials must be deployed. India requires transitioning from hazard prediction to impact prediction.
The hazard environment in the Himalayas is changing. Changes in temperature and climatic conditions have influenced rainfall patterns and the behaviour of glaciers and slopes, while roadways, tunnels, hydropower plants, tourist destinations, and development in general are increasing in fragile regions. Satellite imagery, remote sensing, automatic devices, drones and artificial intelligence technology can help a lot in monitoring. But technology alone is not enough for preparedness. A warning displayed on a government dashboard is not very useful if it does not reach those affected by it. Villagers, farmers, schoolteachers and families have to know what it means and what needs to be done to protect themselves. Equally important is the local knowledge about which embankments will collapse first, which roads will become impassible and how floodwaters will inundate their villages. Thus, the goal should be to define the affected population, identify critical infrastructure, evacuate routes and places, as well as position trained local teams and relief forces beforehand.
Lessons from Uttarakhand
The recent catastrophe in Nepal makes us recall a lesson that India had been taught earlier. The disaster in Uttarakhand clearly showed the interaction of heavy rains, floods, landslides, geological instability, settlements, infrastructure and development. The basic lesson learned was obvious: natural hazard turns into disaster due to the vulnerability of society.
The lessons teach us about zoning, restrictions on building in risky zones, Disaster Impact Assessment along with Environmental Impact Assessment, slope stabilization, protection of ecosystems, better warning systems and community preparedness. But still: do we learn from disasters or merely document them?
The solution does not lie in halting development. Connectivity, growth and security depend on roads, tunnels, hydropower and tourism infrastructure. The question is where and how such development happens.
Development in the mountains cannot happen in the same way as development on more stable terrains. Geomorphological and environmental assessment is crucial for any hydropower or tunnel project. Consequently, Disaster Impact Assessment must become a necessary element of infrastructure development in fragile Himalayan regions.
Nature needs to play a role in disaster-risk reduction as well. Forests, wetlands, stable slopes and healthy water catchments protect from erosion, runoff and siltation. Thus, their conservation and restoration should become complementary to engineering solutions.
Transboundary Himalayan Resilience Agenda
The Nepal tragedy proves one thing for certain: disaster resilience in the Himalayas must be transboundary in nature. India and Nepal must work together to create a Himalayan transboundary disaster risk management framework taking into account their shared hydrological basins. Satellite imagery, glacier and glacial lake assessment, avalanches and landslides monitoring, earthquake data, precipitation forecasts and river level monitoring should all be integrated into early warning and impact forecasting system.
The response has to be proactive, not reactive. There should be no need for downstream governments to react only after the disaster crosses the international border, but the warning must come before the flood does.
We have to shift our approach from relief to risk reduction, from hazard assessment to impact prediction, from project-level initiatives to regional water basin planning, and from national activities to transboundary cooperation.
Bihar and Uttar Pradesh should take note of this particular alarm. The lives of people downstream will rely heavily on choices being made thousands of kilometres away, perhaps even outside of India. The Himalayas are not only a natural dividing line between countries; they are a single, interconnected ecosystem.
While we cannot control our geography, we can definitely change the way we respond to whatever our geography may present to us. The real choice is not development versus disaster-risk reduction. It is risk-blind development versus risk-informed development. This was the message that Uttarakhand delivered to us, and Nepal's misfortune serves to reaffirm it. In case the Himalaya shakes, the plains must be ready. If we want to secure people, infrastructure, agriculture, energy systems and ecosystems of the Himalaya-Ganga basin, one rule must reign supreme: The river basin, not the political boundary, should be the basic unit of disaster-risk management.
The larger concern about the floods from Nepal comes not just from the Gandak, but also from the Rapti and Ghaghra systems, which link Himalayan catchments with eastern Uttar Pradesh. The Bagmati, Kamla and Kosi rivers connect Himalayan catchments with Bihar. These particular rivers have been listed by the Government of India as some of those contributing to flood situations below Nepal
The writer is former Executive Director, National Institute of Disaster Management, Government of India; Views presented are personal.
