Sand Dams: A Sustainable Solution for Water Scarce Regions

Sand dams provide a sustainable solution for water-scarce regions as climate change kicks in. They are easy to build and maintain, and last for decades. They provide water, particularly in arid regions, for people of all income levels – but are particularly beneficial to low-income, disadvantaged households and women. Sand dams also benefit the local ecology.

Fast facts:

19 sites in 3 regions of active pilot;
1,000 direct beneficiary households;
USD 150,000 direct investment.

The problem

Global and regional studies reveal that climate change will adversely affect the availability of surface water resources in the sub-Saharan region. The anticipated impacts of climate change include severe droughts and overall drying in most parts. Such impacts are already evident in the region, and include the drying of small streams. This not only negatively affects the livelihoods of communities, but also harms aquatic life dependent on the ecosystems.

The solution

With the support of partners, including UNDP, sand dams are being built in Swaziland to ensure a sustainable supply of water throughout the year. Sand dams consist of a concrete embankment built across seasonal streams that flow during the rainy season, and run dry during the dry season. Sand can hold a relatively high proportion of water for an extended period of time. The water can be accessed from the sand in two ways: by using traditional scoop holes, where water is accessed by digging holes upstream from the dam; and through installation of infiltration galleries that drain into shallow wells, where water is then extracted with either a solar pump, hand pump, or submersible electric pumps.

Sand dams are a low-cost investment infrastructure built in close collaboration with the communities. The project provides all outside material such as cement, steel, and pipes, while the community gathers all natural materials such as sand and stones. There is no sophisticated technology involved, except for pump installations. The dams can last for more than 100 years without major refurbishment.

Helping the planet

Sand dams provide a sustainable water source, and conserve ecosystems by raising the water table around them. Natural vegetation and biodiversity dependent on aquatic ecosystems near the sand dams also benefit.

Helping people

The sand dams help communities adapt to climate change by ensuring water availability throughout the year for both people and livestock. Proposed income-generating activities in this project include the establishment of gardens, nurseries, orchards, and fisheries. Furthermore, sand dams reduce time needed for community members to collect water, which they can then spend either doing schoolwork or income-generating activities. The dams are thus particularly beneficial to poverty-stricken communities, and will also help to ensure food security.

Sand dams are low-maintenance and their impact increases as they mature. Waterborne diseases that result from drinking dirty and unsafe water – which are currently reported to be high around the project areas – are expected to be significantly reduced with the sand dam intervention; the sand acts as a natural filter for the water and therefore improves its color, taste, and odor.

Scaling up

For long-term sustainability of the project, communities have established funds to maintain the distribution system. An established community committee manages the funds. Aside from maintenance, the fund will help the communities establish further sand dams. This scheme makes the project highly replicable in any community or country. More partnerships are still being organized with other organizations to continue funding future programs working with communities. Given the expected impacts of climate change and the local enthusiasm for the project, the future is looking bright for more sand dams, in Swaziland and beyond.