By Henry Neondo
The massive potential of rainwater harvesting in Africa is underlined in a new report released today at the climate convention talks in Nairobi.
The report, compiled by the United Nations Environment Programme
UNEP) and the World Agroforestry Center, concludes that many communities and countries suffering or facing water shortages as a result of climate change could dramatically boost supplies by collecting and storing rain falling freely from the clouds.
Kenya, for example, with a population of somewhere under 40 million people, actually has enough rainfall to supply the needs of six to seven times its current population.
Ethiopia, where just over a fifth of the population are covered by domestic water supply and an estimated 46 per cent of the population suffer hunger, has a potential rainwater harvest equivalent to the population needs of over 520 million people.
Not all can or should be harvested for drinking water and agricultural uses. Indeed over a third of rainfall is needed to sustain the wider environment including forests, grasslands and healthy river flows.
It makes the actual rainwater harvesting potential somewhat less but still much more than adequate to meet a significant slice of population needs.
Until recently the importance of rainwater harvesting as a buffer against climate-linked extreme weather events has been almost invisible in water planning with countries relying almost exclusively on rivers and underground supplies, says the report.
UNEP and the World Agroforestry Centre are urging governments and donors to invest more widely in a technology that is low cost, simple to deploy and maintain, and able to transform the lives of households, communities and countries Africa-wide.
Unlike big dams, which collect and store water over large areas, small-scale rainwater harvesting projects lose less water to evaporation because the rain or run-off is collected locally and can be stored in a variety of ways.
The report says rainwater harvesting also holds important potential for assisting managers of protected areas with the technology already having been tested to help wild animals in places like Nairobi and Tsavo national parks during drought.
Achim Steiner, UN Under-Secretary-General and UNEP Executive
Director, said: “The figures are astonishing and will surprise many. It is important to emphasize however that it is not desirable, realistic or environmentally sensible to harvest every last drop for human needs.
Nevertheless, the numbers do underline the huge untapped potential for rainwater harvesting as a promising adaptation measure for coping with climate change that has largely gone unnoticed”.
“Over the coming years we are going to need a range of measures and technologies to capture water and bolster supplies. Conserving and rehabilitating lakes, wetlands and other freshwater ecosystems will be vital and big dams, if sensibly and sustainably designed and constructed, may be part of the equation too. However, large-scale infrastructure can often by-pass the needs of poor and dispersed populations. Widely deployed, rainwater harvesting can act as a buffer against drought events for these people while also significantly supplementing supplies in cities and areas connected to the water grid”, he added.
“Rainwater harvesting can also assist in meeting wider aspirations, including the Millennium Development Goals as they relate to fighting poverty and hunger, delivering environmental sustainability and gender equality. Maasai women, taking part in a pilot in Kisamese, Kenya, are gaining four hours in a day because of the reduced demands on their time to find and fetch water. Having water supplies on their doorstep has thus liberated them from a daily chore, giving them more time to spend on education, child-care, cultivation and alternative livelihoods”, said Mr Steiner.
Dennis Garrity, Director General of the World Agroforestry Centre, said: “In the popular mind. Africa is seen as a dry continent. But overall, it actually has more water resources per capita than Europe. However, much of Africa’s rain comes in bursts and is rapidly swept away or is never collected. The time has come to realize the great potential for greatly enhancing drinking water supplies and smallholder agricultural production by harvesting more of the rain when and where it falls”.
“Some countries are already successfully exploiting their rainwater. In South Australia, over 40 per cent of households use rainwater stored in tanks as their main source of drinking water. Germany has over half a million rainwater harvesting schemes. So this is not a second rate technology but a first rate, low cost one. It is a technology that needn’t await further research and development. With little adaptation it is available now”.
Last week Kenya’s water minister announced plans to require all new buildings to include rainwater harvesting measures and similar plans have been drawn up in India where, via work coordinated by the Barefoot College, some 470 schools and community centres now collect 29 million litres of rainwater in regions where conventional supplies are unsafe as a result of salt contamination and metals.
The impact on lives and livelihoods of rainwater harvesting is underscored by a five-year-old project established by UNEP and the non-governmental organization EarthCare Africa with funding from the Government of Sweden. It is also now backed by the Regional Land
Management Unit (RELMA) in the World Agroforestry Centre and the
Rotary Society’s Water & Sanitation Action Group (RWASP).
Rainwater harvesting equipment including containers and mini-reservoirs or ˜earth pans” have been installed in a Maasai community in Kisamese, Kajiado, some 30 minutes drive from Nairobi in the Ngong Hills.
The project has the capacity to store over half a million litres of water and has led to the development of small kitchen gardens and improved agricultural plots that are contributing to food security.
Wood lots, which can be harvested for fuel for cooking, have also been established.
Agnes Mosoni Loirket, a Maasai community leader in Kisamese, said:
“Accessibility of water has lessened the work load and time spent to fetch water. Before the project, some women used to leave early and sleep close to the river, leaving school children going to school unattended”.
RWASP, in alliance with UNEP and the World Agroforestry Centre, are planning to extend the Maasai pilot into other parts of Kenya and