waste water

For the last eight months, photographer Godfrey Mokaya has been building what he calls “his retirement home” in Athi River on the outskirts of Nairobi, Kenyan capital.

In the four-bedroom house, that is nearing completion, Mokaya has put classy fitting to make it cozy.

And one of the last things he is currently constructing before he moves into the house in two months is a biological septic tank, commonly known as bio-digester, which will help him manage kitchen and toilet waste.

“I went for the bio-digester technology to avoid costs that come with using an ordinary septic tank, which must be emptied now and then and the waste sometimes end up in the environment,” he said on Tuesday.

Mokaya is among an increasing number of Kenyan homeowners in urban and rural areas who are embracing the green technology to manage waste from their houses.

The bio-digester is slowly replacing septic tanks in Kenyan homes, with the latter regarded as outmoded and expensive in the long-term.

“I learnt about the technology from a friend who built his house and installed a bio-digester there. It has served him well for the last three years,” he said.

In addition, living in an apartment block in Syokimau not far from where he is building his house, Mokaya has seen the landlord keep on emptying the septic tank every month. He thus knew the technology to go for as he built his home.

While most parts of Nairobi are linked to the main sewer line, suburbs on the outskirts like Syokimau, Rongai, Athi River, Ruai, Ruiru, which are considered the city’s bedroom, are not.

Residents in the suburbs, therefore, have been relying on septic tanks, with some landlords of high rise buildings emptying the tanks every week.

The situation has, therefore, built a vibrant exhaust services business for lorry owners, with a trip costing 10,000 shillings (100 U.S. dollars).

“With bio-digester, you forget such costs because the waste is converted into water and it filters into the ground via the soak pit. So you will never need to exhaust the refuse,” businessman and homeowner Amos Karuthi, who is based in Ruai, said on Tuesday.

It costs an average of 1,000 dollars to construct a good bio-digester, which also comes with a soak pit, according to Karuthi.

He initially went for a septic tank but converted it into a bio-digester after emptying twice in about a year and paying heavily for it.

Robert Kariuki, a bio-digester specialist with Hallmark Builders in Nairobi, noted that the biological tanks incubate bacteria which decompose waste, therefore, one does not need to empty the facilities.

“Bio-digesters save space, are cost friendly in the long-term and cannot fill-up. If well made, they cannot return smell in the house, need little maintenance and are environmental friendly,” he said, adding that for domestic use, the facility only requires about a meter square to be constructed.

He observed that many consumers are looking for environmental friendly, cost-effective way, therefore, biological tanks offer the convenience.

With many Kenyans becoming conscious of the need to conserve the environment, use of the green technology is gathering pace especially in urban areas on the outskirts of Nairobi, where tens of citizens are building homes.

Kariuki noted that water from the bio-digester can be recycled to water plants and harness green energy for cooking and lighting from the system. Enditem


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