Asia’s water supply under threat from climate change

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Out of world’s estimated 1.1 billion people without access to safe water, nearly 70 per cent or 700 million come from Asia and the Pacific regions.

Many countries are already experiencing an increasing scarcity of water, particularly during dry seasons, and climate change will exacerbate this situation.

An Asian Development Bank (ADB) report released on Saturday says that more than three quarters of the countries in Asia face serious water shortages, which if not managed, poses a real threat to continued growth and prosperity for the region.

The reasons are many, complex, and intertwined, ranging from a rapidly growing population, increasing and diversifying food demands, urbanisation, unsustainable land-use change, to the excessive extraction of groundwater, water-related disasters, and climate change.

Climate frontline:

Asia is on the frontline of climate change impacts both in terms of exposure and vulnerability. In parallel, climate impacts are most keenly felt on water resources.

Estimates for Asia predict a 65 pc increase in industrial water use, 30 pc increase in domestic use, and a 5 pc increase in agriculture use by the year 2030.

By 2050, 64 pc of Asia’s population will reside in cities, while more than 50 pc of urban residents already live in low-lying coastal zones or flood plains.

Providing more food, energy, clean drinking water and access to sanitation without compromising the environment is even more challenging with a backdrop of climate change impacts and the risk of water-related disasters.

“Regional studies show that as climate change advances, we are likely to see a destabilising effect on the world’s water systems, with significant impacts in the Asia Pacific region,” said Vijay Padmanabhan, Technical Advisor for the Water Sector Group at ADB. “Planners can no longer rely on past climate data to accurately predict water needs. We will instead see more instances of extreme weather.”

In some areas, there will be longer periods between rainfall, requiring increased water storage, both at local and regional levels, for surface water as well as groundwater.

For megacities with vast populations, large reserves of accessible freshwater must be held in readiness for periods of drought or other natural disasters.

Energy production that relies on the steady availability of water will also be jeopardized. Meanwhile, crop yields on rain-fed land are likely to decrease, and more resilient crop varieties may need to be developed and introduced.

“Finding solutions to Asia’s water challenges means addressing a labyrinth of complexities and taking innovative approaches that will enable us to do ‘more with less’,” added Yasmin Siddiqi, an ADB Principal Water Resources Specialist.

“We can only achieve this if we recognise water as being intrinsically linked across all users and shift away from conventional, piecemeal approaches.”

For example, water for agriculture uses at least 70 pc of available freshwater, through either rain-fed or irrigated systems.

One way to tackle the water and energy scarcity is by increasing the efficiency of land, water, and energy use in agriculture, including better management of irrigation systems, using improved seeds, more accurate application of fertilizers and pesticides, and improved irrigation technologies.

Pakistan shortly in ‘water scarcity league’:

In an ADB report released earlier in 2007, it was stated that Pakistan was already in the water stress league, the water stress threshold being defined as renewable water resources below 1,700 cubic metres per person per year “and will shortly be in the water scarcity league”.

It is said the water use value in Pakistan was ‘zero’ – meaning very poor in efficiency. It noted that this value should improve from zero to 40 as soon as possible.

The report said that in Karachi and several other major cities, water demand already exceeded production capacity by a considerable margin.

Stockholm focus on water security:

The overall theme of World Water Week this year is “Water for Development.” In this connection, ADB is organising a day-long Eye on Asia event on August 25 to promote understanding of water security as a key to Asia’s development and its relationship to the upcoming sustainable development goals.

Eye on Asia will include sessions on household water; water for cities; and innovations in water, energy and food.

ADB will be highlighting the challenges and approaches to addressing water security at the World Water Week this month in Stockholm.