How Sand dams are quenching thirst in Kitui

Animals drink from a pool at one of the newly built county government sand dams across River Mutwaewa in Mwingi West. The sand dam is already filled up with water. [Philip Muasya, Standard]

With many parts of Kitui County prone to water insecurity owing to prolonged drought periods that run from April through to October every year, an ingenious water conservation technology has proven to be a permanent solution for the local residents.

The solution has come in the form of sand dams, which are reinforced, specially designed concrete walls built across seasonal rivers and which for the last 10 years have proved to be an all time solution to the constant water scarcity in the county.  

The cemented walls built from the river’s rock base, work by storing huge volumes of water under heaps of accumulated sand over a period of time.

Paul Kaleve, the county irrigation engineer and an expert in sand dam technology, says that the bigger the volume of sand trapped, the higher the volume of water stored underneath.

Kaleve explains that sand dams re-charge the underground aquifers thereby raising the water table with minimal evaporation rates.

The success of this technology is seen in parts of the county where the structures were constructed either by the county government or non-governmental organisations. So far, the county government has constructed them on dozens of seasonal rivers across the vast county as part of efforts to make the region water and food secure. 

Vincent Ngomo of Yuumbu GNCA child development centre in Ikutha ward shows a sand dam across Kithini River constructed at a cost of Sh5.9 million to supply water to residents of three locations. A two acre demonstration farm is under drip irrigation thanks to the sand dam. [Philip Muasya, Standard]

With the ongoing rains, newly constructed ones are already filling up with the ongoing rains, much to the residents’ relief.

At River Kithyoko in Mwingi West, a sand dam, which was among the first to be constructed in the county, has become the lifeline for local residents.

They can now produce enough food for their domestic use as well for income generation. Besides, there is sufficient water for domestic and livestock use.

Alice Wayua is one of the small holder farmers in the region who plunged into small scale irrigation farming four years ago and has never looked back. She says the availability of water gave her the kick to go into farming.

The success of this project is compounded by two sump wells, basically underground cemented water tanks, that were constructed next to the sand dam and fitted with a giant pipe and solar system to pump water from the sump wells to raised water tanks about 600 metres away. From here the locals are able to utilize the water as they wish.

“Through farming, I produce enough food for my family and also for sale in the market,” says the 26 year old mother of three. At every visit to Kabati, Katutu and Kithyoko markets where she sells her produce, mainly vegetables, Wayua earns between Sh6000 - Sh8000 in a day. She goes to the market three times per week.

“This is my livelihood and I cannot waste time looking for another job. Sand dams should be replicated all over the county,” Wayua says as she harvests sukumawiki and spinach ready for the market.

In Waita ward of Mwingi Central, Anne Mwandikwa descends at River Mutwaewa and heads straight to a shallow, sandy well, her donkey leading the way. Using a calabash, she drains the well by scooping the accumulated pool and waits for a few minutes, ready to fetch.

“You have to drain the well first if you want to draw clean water,” she explains, methodically scooping and filling up four jerricans. In about 10 minutes, she is done and ready to head back home. About 100 metres downstream, a herd of cattle, goats and donkeys are having their fill at a pool of water accumulated behind a newly constructed sand dam by the county government. The sand dam is 100 metres below another one constructed in 2012.

To Mwandikwa, this is some kind of a miracle. She says before the sand dams, just before the onset of rains towards the end of October, the river would ordinarily be dry. She recalls the miserable past where they would spend nights at the then barren river, huddled in deep wells.

 “There was not enough water for us, let alone animals. Men would form a human chain to descend down the wells to draw water for us,” she says. Thanks to the two sand dams, the river at this section has burst into life and water is in plenty.

Kitui County executive in charge of water and irrigation Peter Nkunda describes the sand dam technology as a game changer, particularly for the arid and semi arid county, saying it addresses water insecurity and brings out the component of food security through small scale irrigation farming.

This financial year, the county government has set aside Sh120 million to construct 497 sand dams with the ultimate plan of constructing 60 in each of the county’s 40 wards in line with Governor Julius Malombe’s priority of ensuring water security for the county residents.

Nkunda says that sand dams are ideal for the county because they are cost effective and low maintenance water conservation structures that retain water over a long period while improving the water table.

“Due to prolonged droughts, ground water levels have been decreasing, therefore we have found that harnessing surface runoff through sand dams is more promising than sinking boreholes,” explains Nkunda, adding that sump wells were also being constructed next to the sand dams to encourage irrigation farming throughout the year. The wells will be solarised to cut on the costs of electricity, he says.

For food security to be achieved at household level, the officer says farmers will be trained and empowered on irrigation farming around climate smart agriculture.

“The county has 11000 hectares of potential land for irrigation farming. What is in use currently is only 3000 hectares that is why we want to expand the arable land to 70 percent in the next five years,” he says.

To actualise this, the county government has identified areas where irrigation schemes will be established in over 40 clusters to enhance food security and improve people’s livelihoods. Of these, 26 are being set up this financial year.

The food security component is also gaining root at Yuumbu village in Kitui South where a sand dam funded by Compassion International is showing all the signs of success.

Here, the NGO partnered with Good News Church of Africa (GNCA) to construct a Sh5.9 million sand dam across Kithini stream, and a high volume underground well.  Ikutha Ward being one of the driest areas in Kitui county, results of the sand dam are already visible.

During our visit, we found a team of local farmers at the church’s two acre demonstration farm where an elaborate drip irrigation system has been laid out powered by solar energy.

“Farmers are excited to visit our farm and gain on-farm knowledge on what they can do with sufficient water supply. The structures have given us enough water to do irrigation farming,” says Vincent Ngomo, the director of programmes at Yuumbu GNCA child development centre.

He says the food produced here goes to feed the vulnerable children under the support of the organisation while the surplus goes to markets to generate revenue. Next to the farm is a section fitted with taps where locals access the water at a small fee. A reverse osmosis technology ensures that the water is cleaned and cleared of salinity.

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