Storing water to adapt to climate change

This policy brief, published by the International Water Management Institute (IWMI), considers water storage options for adapting to climate change.

Storing water spurs economic growth and helps alleviate poverty because it makes water available when and where it is needed, say the authors. But many developing countries have insufficient water storage capacity to cope with today's variability in rainfall and temperature, let alone with the more extreme variations expected with climate change.

In Ethiopia, for example, the lack of storage infrastructure means farmers cannot cope with droughts.

The authors argue that more water storage is essential if developing countries are to secure reliable water supplies for agriculture and other uses. But storage solutions must be tailored to a region's specific needs and socioeconomic conditions, they add.

They describe several water storage options — including large reservoirs, small ponds and tanks, soil moisture, aquifers and natural wetlands. For each option, the authors examine the benefits and drawbacks, as well as the possible biophysical risks connected with climate change.

The key to designing water storage solutions to withstand the uncertainty associated with climate change is to combine the unique characteristics from a range of storage types.

Effective storage methods can be simple and cheap, say the authors. Ponds and tanks for individual households, for example, may be small in volume but can prove vital in supplementing domestic and subsistence agriculture water supplies.

Thousands of small community dams in Burkina Faso and Ghana show that small-scale storage options can effectively improve smallholder water security.

Whatever water storage options are chosen, the authors emphasise that these should be just one component of a multipronged approach to adapting agriculture to climate change that also includes improving food storage and water management practices.

Link to full policy brief from the IWMI  [733kB]