A rush to the rivers below the country’s drying towns bares new promising groundwater levels, our Staff Writer JAMES CHAVULA writes.
When taps in Balaka town run dry a year ago, residents endured lengthy queues for trickles from water bowsers and boreholes where lofty stacks of buckets became familiar sights.
The drying of Mpira Dam in Ntcheu in July 2018 left those who could not stand the fierce scramble fetching drinking water from contaminated wells.
“It was survival of the fittest,” recalls Anita Phiri. “Everyone needs water, but there wasn’t enough for everyone.”
The water stress seems over and taps run all day, thanks to rising dam levels and newly-installed electric boreholes.
However, the rush for groundwater has unearthed optimistic insights into dry towns.
Last year, the World Bank engaged Foundation for Irrigation and Sustainable Development (Fisd) to install boreholes yielding no less than five litres every second into Southern Region Water Board (SRWB) pipelines. Astonishingly, the contractors say they have hit underground vaults that produce up to four times the desired minimum.
Explains Fisd director Frank Mwenechanya: “We worked with SRWB to find sites where we could drill to get the required yield. Interestingly, one borehole in Balaka yields 20 litres a second and the other produced 22 litres.”
The drillers got 28 litres a second in Mwanza, a semi-arid district.
“In most of the eight sites, we haven’t found less than 10 litres per second. Mwanza is a tricky terrain, but we got the highest yield in our history,” he says.
Mwenechanya and three other water engineers founded the water and energy company in 2005, a year after they graduated from the Lilongwe University of Agriculture and Natural Resources College.
Besides the Balaka feat, the second boreholes in Mwanza pumps 12.5 litres a second apiece, those at Mloza in Mulanje and Nchalo in Chikwawa hit about 10 litres per second. Only the one in Neno “was very dry”.
“After drilling 120 metres deep, we could only get 3.5 litres a second. The rest yielded more,” says Mwenechanya.
The twin boreholes at Chamangwana Village, Balaka, are adjacent to an artisanal well, which waters a tomato field all day.
The flatland could be a game changer in the way SRWB supplies Balaka, according to Mwenechanya.
“There is a lot of water. In fact, we abandoned a borehole yielding 10 litres per second because we wanted higher yield for dry times. If we use this groundwater wisely, Balaka’s water scarcity should be history,” he says.
The good news for rapidly growing populations struggling with drying surface water brings into question indications that Malawi is getting dry.
“Literature shows that groundwater is not increasing, but it’s drying at a time we need it most. How come they are finding these high yields? This contradicts what we know so far,” says Kamoza Msonda, chief water resources officer in the Southern Region.
Jacqueline Dias, civil engineer at SRWB in Balaka, says the readings were “100 percent verified” by the water board.
“It’s a huge relief because we don’t own Mpira Dam. When our colleagues want to close the dam, they close. They don’t allow us more than the required 30 percent of their water,” says Dias.
According to World Bank senior disaster risk management specialist Francis Mkoka, the project to tap groundwater for dry towns started in 2016 when most water boards couldn’t meet the demand.
“We know drought will happen, so we approached government to make the system resilient and sustainable,” he says.
Mkoka debugged the promising yields.
He said: “Balaka is known as a dry land, but groundwater could be the solution to the water woes.
“The major problem is that we are not interested in storing water under the ground or recharging the aquifers. We need to invest in catchment protection so that there are no run-offs. What we are doing now, even the tree-planting exercises, is not enough to protect groundwater.”
Mkoka calls for new groundwater studies into the state of the country’s aquifers.
“Even scientific studies show yields of groundwater in the country are dwindling, so this is strange. We need new data to bring us to the comfort zone where our friends are,” he says.
Fisd is laying a 4-km pipeline to the 1.5 million-litre tank at Sosola Treatment Plant. From the reservoir, the water from the high-yielding boreholes will flow by gravity to over 5 700 taps across the town which gets about 20 new connections monthly.
“It’s not just about getting a lot of water from the ground, but how many people will benefit and whether we are serving them sustainably,” says Mkoka.
Progress looks OK
John Kumwenda, director of water supply services in the Department of Water Resources, says groundwater increases the growing population’s resilience to weather shocks caused by climate change.
He explains: “We need a contingency plan. If we don’t have water in surface-water-sources as was the case in Mpira Dam last year, we can switch to other sources.
“Interestingly, the high-yielding boreholes can run on solar energy. Escom has already connected the new boreholes in Balaka. If Escom experiences a blackout, we have abundant sunlight here.”
Kumwenda says his department will install a monitoring well at Chamangwana to track groundwater levels and ensure the promising aquifers are used sustainably.
Balaka draws 30 percent of the water in Mpira Dam, which has been hit hard by deforestation and prolonged drought.
SRWB chief executive officer James Chitete says “the progress looks OK” even though we are lagging behind.
“We hope to have water in Balaka by November 30. So far, we have drilled three boreholes with a combined yield of over 50 litres per second. Two are funded by World Bank and one by the water board. We have a long-term project to pump water from the Shire River in Liwonde to Balaka.”
Beyond dry districts
SRWB is waiting for Parliament to authorise government to obtain a loan for the extraction of water from the country’s largest river, some 30km east of Balaka.
However, the silted river keeps dwindling due to drought and deforestation on its banks.
In this case, the high-yielding boreholes are not just add-ons, but reliable backup in lean times.
Says Mwenechanya: “The volumes obtained are exciting. People believe one cannot obtain more than 20 litres a second, but we did it in Mwanza, Balaka and Ntcheu. These are dry districts, so why can’t we do it in better-off districts surrounding Lilongwe or Blantyre?
“This should open people’s minds that we might be having a lot of groundwater they can also use to irrigate their farms instead of growing crops too close to rivers. If we harness this water, we can overcome hunger and poverty. n