Every year, we have about 76 disasters in the Himalayas, some 36,000 people are killed and over a million affected by disasters. The loss of life and damage does not need to occur. How people manage the situation can relieve the situation much better.
About a third of these disasters are from floods. In the Himalaya, there are two broad kinds of flooding:
- riverine floods, where the rivers swell up and overtop their banks
- flash floods which are caused up in the hills from rapid rainfall, from glacial lake outbursts, from cloudbursts.
Also quite common are landslide dam outburst floods. Lots of times landslides come down and block the river; the dam breaches and causes intense flooding.
The mountains, and the rivers coming from the mountains, typically cross national boundaries. Big riverine floods are very often transboundary floods. This is true also of many flash floods as well. Only about 10% of floods are transboundary in nature, they displace 60% of people . Right now, there is a lack of exchange of real time data. We have some bilateral agreements and treaties, but there's a door open for much more regional cooperation in floods.
Rather than living with floods, we have decided that dykes are the way to go. If well maintained and managed, it's an effective measure. But if you don't maintain and repair dykes then even with a moderate rise in water levels, we have huge floods like the devastating Kosi Barrage flood. The message here is that better maintenance, better planning, perhaps even better ways of thinking through flooding really makes a difference.
From previous floods, we have learnt that we do have huge data gaps. We are missing those communication systems that could really help us out. We can do better at flood infrastructure and planning. There is a need for transboundary cooperation to deal with many of these flood events.
What are some of the solutions?
To immediately fill some data gaps: When it comes to weather stations, at lower elevations, we have plenty of data stations. This decreases as we go higher. We don't have information about weather at high altitudes. We need to get weather stations up high. There are huge improvements in the technology for determining rainfall using satellites that can be made to make up for the lack of data stations. We still need the data stations to calibrate those.
Regional flood information systems: There is one for the Himalayan Hindu Kush region ( HKH-HYCOS) that we can take better advantage of, where we can share information across borders. HYCOS is trying to set up an end-to-end system where we can share data and get that data moving across borders 'at a rate faster than floods' as the motto says.
Localised warning systems: For the really localised flash floods, people can employ some almost homemade gadgets. One such example being used in Assam is of a device that simply detects the water level in a stream. When the water level goes up, it sends up a signal to an alarm or a telephone system.
Community training: Local warning systems require that the communities are trained to use this type of system so that they don't have to wait for someone very far away. If we think of migration and of men moving out of villages, we have to be paying attention to women and making sure they are protected from floods.
A mix of high-tech, low-tech, government systems as well as a community level approach is going to see us through.
Rethinking hydropower stations: There is a dramatic melting of glaciers and a resultant formation of glacier lakes. These lakes are putting people and the many hydropower stations at risk. We have to think how we are going to rethink these hydropower stations by taking into account the threats from these glacial lake outburst floods (GLOFs). Planning where infrastructure is going to be put needs to be talked about.
It is possible to build these kind of end-to-end systems. I think that it is possible, and we need to link science with government and communities. We can do much better with our infrastructure planning and management. We have come a long way with transboundary information systems and really do much better with cooperation.
So the message is, there are floods and there are disasters. Let us make the next one, the next flooding event, something that is not so big a disaster by working together on this.
This post is an extract of a speech made by David Molden, Director General of International Centre for Integrated Mountain Development (ICIMOD), at the Sustainable Mountain Development Summit (SMDS) held at Nagaland in September 2013.