Let the water flow

Could solar-powered desalination help boost drinking water supplies in Kenya and beyond? Anthony Langat speaks to people who think so.

A woman sits in a doorway preparing fish
Mwanamkasi Ali prepares food using the desalinated water from her work place. By Anthony Langat

Mwanamkasi Ali sits in the door frame of her coral-rock and tin-roof house, hunched over a yellow bucket, descaling and cleaning fish she will later cook for lunch. The 35-year-old lives in Majengo village, in Shimoni, on the shores of the Indian Ocean in Kenya. Her house is in the middle of the village near the mosque and the borehole.

Majengo is so close to the sea that the water from the borehole is salty – and it’s the same in many other places along the coast. Two months ago, Ali would have cooked up the fish using this water. She and her children also drink it, despite its unpleasant taste and potential damage to their health. ‘For many here, this water had become normal,’ she says. But now, a new project is trying to change that.

Kassim Musa, an employee of Bilal Muslim Mission, cycles past Ali’s house with four empty jerry cans, rattling on his carrier. A few metres away he hops off the bicycle, unties the cans and sets them outside the water kiosk. Musa is in charge of a unit that desalinates and purifies water from the borehole. Together with seven other young men he distributes it to clients in Shimoni, for a small fee.

For many here, this salty water had become normal’

Ali works part-time with Musa at the water-point, which was developed by Kenyan start-up Water Kiosk and Winter, a German company which supplied the technology. Bilal Muslim Mission funded the construction of the water kiosk and manages it.

According to UNICEF, just 59 per cent of people in Kenya have access to safe drinking water. The coastal counties are particularly affected – as are the northern regions.

Prior to the installation of the desalination unit in Majengo, access to clean drinking water was difficult and expensive. A few vendors ferry water from Kidimu, 14 kilometres away, by pickup truck and motorcycle, for sale mainly to the 5,000 residents of Shimoni. It costs around 40 shillings ($0.40) per 20-litre can.

Many will opt to use the salty water straight from the borehole to save money. Mariam Ropa, who runs an open-air street-food restaurant near the mosque, says that although she cooks using the salty water, not many customers like their tea made with it. So, she started to buy water from the Majengo vendors. ‘The water they sell isn’t clean enough, but it is better than the one from the borehole,’ she explains.

A man sits at a window wearing a blue t shirt
Kassim Musa inside the Water Kiosk in Majengo. By Anthony Langat.

Water supply falls under the jurisdiction of counties in Kenya’s devolved system of governance. A few years ago Shimoni did have piped water but it ran for a few months and then ‘collapsed due to mismanagement’, according to Hussein Shambi a coordinator of the Bilal Muslim Mission of Kenya.

Ropa would prefer it if the government provided clean drinking water in Shimoni. ‘I would make more profit from my restaurant as I wouldn’t have to spend more money on water,’ she says. There are places in Kenya where the government has provided water and the charges per unit are much less than from the private sector. Water.org, a global NGO that works in Kenya, states that the average water bill of a typical household in Nairobi, one which is connected to a piped system, is only $4.46 per month – compared to $38 in average total coping costs resulting from an unreliable or distant water supply in rural areas.

In Shimoni, the water from the new Majengo desalination unit is much cheaper than the other options and is sold at $0.10 per 20-litre jerry can. However, if one needs the water delivered to the home, Musa and his group of young workers charge a fee ranging from $0.10 to $0.20, depending on the distance.

Desalination of water has long been an option to improve water access in coastal areas. However, the cost and type of energy has been a concern.

Conventional desalination technologies generally use fossil fuels and are best suited for large scale applications. Other challenges include minimizing harm to marine ecosystems, and the need to dispose of brine – a waste product which is usually dumped back into the sea and needs to be managed carefully to avoid environmental damage. In the Water Kiosk process waste water is recycled, thanks to the lack of chemicals used. At some units it’s used for fish and crop farming.

Just 59 per cent of people in Kenya have access to safe drinking water

According to Sam Kinyanjui of Water Kiosk, their offering ensures that the cost of desalination is kept low while the use of solar energy ensures that carbon emissions are also kept to a minimum. ‘It runs on the principle of reverse osmosis, removing the salts and impurities to retain fresh drinking water,’ he says. ‘We also eliminate the use of chemicals in the purification which then reduces the operation and running costs.

‘This also does away with the risks of underdosing or overdosing, which comes up because water from different places and periods calls for varying dosages of chemicals for purification. Such underdosing could lead to poisoning and threats to human health,’ he says.

The solar panels installed on the water kiosks have a capacity of 11 kilowatts and can purify 20,000 litres per day. This capacity is more than enough to serve its clientele. In Shimoni for instance, the system only neds to run for a few hours every day.

Water Kiosk mainly works with organizations like Bilal Muslim Mission and sometimes governments to install the desalination systems. So far, it has installed 28 systems in Kenya and is hoping to increase this number to 60 by the end of the year. The majority are along Kenya’s coast and up north in the semi-arid areas of Marsabit and Wajir. It is also moving to Tanzania; two are already installed in Zanzibar and five in hospitals on Tanzania’s mainland.

Kinyanjui is positive that it’s possible to have clean and affordable water across the country. ‘Some of these places where water is a problem have challenges like inaccessibility, insecurity but once these are addressed then it is doable,’ he says.

It seems that solar desalination could be a welcome remedy to the lack of access to drinking water in many places. Solar energy is a resource readily available in Kenya. Now it just needs the government to get behind it.