Onwards to a future of grey and black water
Mbongeni Mguni | Friday January 23, 2015 18:37
In the last years of the Botswana International Trade Fair, a remarkable exhibit attracted scores of bemused visitors. The Water Utilities Corporation (WUC) exhibited a miniature wastewater treatment system with one end consisting of a toilet cistern, seat and bowl filled with black water and solids.
In the middle were a network of solutions, suspensions, beakers, filters and other devices, and on the other end was a solitary tap.
Next to this tap was a plastic tumbler and the Corporation’s personnel (dared) invited members of the public to turn the tap and have a sip of the clear water.
Barely anyone did. Few could even muster the courage to sniff the water or touch it with their fingers.
Experts, however, say in a few short decades, the effects of climate change and a growing population will leave precious room for surliness. Recycled wastewater is the future and plans are already underway in the highest policymaking offices to have it become a part of everyday life.
“We are at the point where we have given the Water Utilities Corporation permission to engage companies to see how much it would cost to treat that water for potable purposes,” Minerals, Energy and Water Resources (MMEWR) minister, Kitso Mokaila, says.
“It’s just a matter of time.”
The minister – now in his fourth year in a troubled portfolio that has witnessed energy and water shortfalls, as well as a downturn in mineral prices – sits forward in his office in eastern Gaborone and strikes the pose of a determined man.
According to Mokaila, government wants the WUC to lead the process and financially bear the load, with official support.
“It’s a question of being financially viable. It should be a function of the private sector doing that (wastewater recycling) and selling the water to the WUC.
“Sometimes we overload ourselves and think we can do everything.
“You will know the true cost of the project once we go to tender.”
A feasibility study commissioned by the WUC a few years ago was favourable, suggesting that the treatment of effluent for potable purposes was indeed possible.
However, plans are also underway to incorporate such technology into sewerage plants currently under construction in Kanye and Molepolole.
Conservative estimates are that a wastewater recycling plant at Glen Valley could cost P100 million, although the benefits would erase the costs in a few short years.
One prominent proponent of wastewater recycling, Boikobo Paya, believes this will be one of the key water sources of the future, next to groundwater and rainwater harvesting.
“If you have that for Glen Valley, the water in terms of operating costs is cheaper than the water coming through the North-South Water Carrier,” the former MMEWR permanent secretary recently told a Botswana Society meeting.
“You can recycle it 20 or 30 times and it is the future, even though this will take a lot of mindset change.
“In the future, you will be flushing that water and also drinking it. Government is on track in terms of having that policy in place.”
Paya also believes in the promotion of greywater harvesting for households, where supplies are harvested from baths and sinks, filtered and reintroduced for non-potable usage.
Greywater is household wastewater not produced from the toilet.
More complex techniques in other countries allow for the harvesting of toilet wastewater, known as blackwater or sewage, through separation mediums and purification systems.
That too, is a possibility, Paya says.
A large part of the success in both wastewater reuse and rainwater harvesting is government policy.
Mokaila recalls an era where every drop of water meant much more to Batswana than today. In those days, rain gutters and containers such as Jojos were a common sight.
Today, it may take a policy change to achieve a mindset change.
“We are recommending to the Ministry of Infrastructure, Science and Technology that we change the building code to say that those things that were standard at the beginning should come back,” the minister says. “Other countries limit the number of toilets and baths you can have in your house, because they don’t want people wasting water everywhere. We are also advising the Infrastructure, Science and Technology ministry.”
The value of water has declined in the eyes of many over the decades of improved access, leading to a situation where wastewater reuse and rainwater harvesting are the future, experts say. Additionally, the low price of a unit of water means many do not feel its value.
“A price of 500 millilitres of bottled water costs P6 and yet the first 5,000 litres of WUC water is charged at P10,” says Mokaila.
“One of the loudest cries is that the WUC is expensive, but people don’t know the cost of moving and treating that water.
“If we made the price cost reflective or reasonable, people would use it differently. They would design their houses very differently. We need people to use water in the same way they began using power when prepaid meters were introduced.” In fact, plans are moving forward for the introduction of prepaid water meters, with the WUC in the process of raising funds from the capital market. Mokaila, however, says government has no plans of unnecessarily raising water tariffs.
“Government does everything to keep costs low for people, but these things are not understood in context,” he says.
“The price of water determines the price of development and you try and balance these.
“It’s the economy of development.”
With Gaborone Dam at record lows, long-term climate forecasts indicating drier seasons for the southern districts and the population still growing, the dynamics of future water supplies appear anchored in a change of paradigm in the consumers.