Sand dams protect water for drought-hit pastoralists in Kenya

OLENARAU, Kenya - Despite the scorching sun, Kirinkle Saruni keeps a watchful eye on his 15 cows grazing by a sand dam.

"I hope water reserves will sustain us until the next rains. Pastoralists from other areas are increasingly coming to the dam for water," said Saruni, looking pensive.

He is one of about 400 villagers in Olenarau, in Kenya's southern county of Kajiado, who make daily trips to the dam to quench their animals' thirst.

Recent rain failures have particularly hit livestock-herding communities across the country, some of whom have lost their entire herds to drought, or are left to walk long distances in search of water.

When rain spells do occur, the barren land is less able to absorb rainwater.

To remedy this, the African Medical and Research Foundation has built 20 sand dams in the area in the past decade. The structures use concrete walls built across river beds to capture and hold rainwater in sand deposits.

During the rainy season, the sand absorbs water, which can then be used in homes and for irrigation in the dry season.

Kenneth Omolo, a project officer at the foundation, said wet sand can retain water for up to a year.

CHEAPER, MORE EFFICIENT

The dams are often less costly and more efficient than other ways of fighting drought such as buying water tanks or digging boreholes, Omolo added.

"A sand dam typically costs $2,900 to build – a job usually done by the residents and construction workers – while drilling a single borehole in the area costs nearly $30,000," he said.

Many newly dug boreholes are prone to drying up after only two or three months, he said, and their water can become too salty to drink.

Sand dams "only trap excess rainwater, so there is no risk of them jeopardising the livelihoods of people relying on the river as a source of irrigation", Omolo added.

Benson Sutek, another resident of Olenarau, used to walk 8km (5 miles) daily in search of water during the dry season before the sand dam was constructed.

"During past droughts many pastoralists were reduced to paupers as their animals died," he said.

"But the water currently in the dam is from the last rains in December and should last another few months. With the dam just a few metres from my home, I get to spend more time tending to my farm and animals," he said.

Saruni and Sutek believe the dam has improved not just pastoralists' fortunes but also those of women and girls, who no longer have to trek long distances for water.

"This allows girls to focus on their studies and women to pursue income-generating activities like selling beads or basic goods at the market," said Saruni.

SAND HARVESTING

Joshua Moshira, the water and irrigation assistant director for Kajiado County, said that the dams have also brought advantages for another group of people: young people who harvest some of the sand that collects and sell it in Nairobi, the capital, to construction companies.

"Although this provides employment for young people and revenue to the county government – that collects a fee for the harvesting of sand – too much harvesting can leave the area exposed to flooding" with too little sand left to absorb water during the rainy season, he said.

He said the foundation had been working to make young people aware of the risks associated with over-harvesting sand - including reducing the amount of water storage possible.

"The government, but also donors and NGOs, should train communities on using natural resources with moderation," he said.

Omolo believes communities should explore other cheap and efficient water technologies to reduce the impacts of climate change, such as collecting runoff from rocky areas in plastic or concrete tanks.