FLOWING
UNDERGROUND
Groundwater holds promise of closing the gap between water supply and demand in the Nile Basin
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FLOWING UNDERGROUND
Groundwater holds promise of closing the gap between water supply and demand in the Nile Basin
November 2022
FLOWING
Within the Nile Basin, more than 70 percent of the rural population is dependent on groundwater. It is one of the most important sources of drinking water for people and livestock as well as wildlife watering. There is an increasing use of groundwater for other economic activities including in irrigation, mining, industries, etc. Groundwater holds the promise of closing the growing gap between water demand and water supply as well as buffering the effects of climate change and variability.
Regardless of its importance and the promise it holds, the resource is under human or naturally induced climatic and non-climatic pressures. There is ample evidence that groundwater is under threat from unsustainable exploitation; climate change (affecting aquifer water levels, recharge, and changes in groundwater regimes), high rainfall variability and land use/land cover changes leading to declining amount of surface/groundwater interaction in different areas as well as pollution (urban pollution and issues associated with high fluorides or salinization). These in turn are impacting water availability, causing changes in quantity and quality of groundwater-dependent ecosystems, affecting groundwater-surface water interaction.
To save her village from the effects of the 2016 drought in the Isingiro district that left several livestock and some people dead, Hajara Nabukaru gathered at least 1,000 signatures from village mates petitioning for the construction of a borehole in the community.
Weeks later, the local government constructed a borehole in her village. It now serves thousands of people from her village and beyond.
“During the severe drought that uprooted banana plantations in Ruhimbo and killed people, that is when we got this borehole,” she narrates.
Before the drought, the village had only one shallow well that was reduced to a sandy pit by the drought. Up till then, the well contained unsafe water.
“We would find dead puppies in the well, remove them and fetch the water. We had no option,” narrates Nabukaru.
For the last six years, the single borehole in Ruhimbo village has been a lifeline for thousands of people in this community and beyond, providing safe drinking water, preventing potential public health problems that could result from consumption of unsafe water and reducing the demand for water placed on the neighboring Isingiro town council water system.
“People converge here in mornings and evenings to fetch water. It is good water. It has no germs and never dries up even in dry seasons,” narrates Aineamazima Phiona, a resident of Ruhimbo village who has used this borehole for the last six years.
Not all groundwater is renewable. Some groundwater, deposited by fossils, does not recharge after it is extracted. However, a good amount is renewable, and therefore is a sustainable source of water for humans – if the environment is protected.
According to NBI, surface water systems, especially forests and wetlands, play an essential role in sustaining water quality and quantity, providing a storage medium for water, and supporting complex ecosystem niches of economic and environmental importance.
The NBI says studies have shown that groundwater availability (or depletion of it) in the region strongly bears on poverty, migration, conflict, school attendance, and human health.
According to Uganda’s commissioner for water resources, planning, and regulation, Dr. Callist Tindimugaya, “groundwater and surface water in some situations are interrelated. There are periods when water in river Kagera is flowing into groundwater.”
But James Byaruhanga, a resident of Omundizi in the Isingiro district of Uganda, says not many rural communities that interact with the environment daily know about this. He highlights the importance of raising awareness about groundwater.
A borehole is a hydraulic structure that withdraws natural underground water from an aquifer. Apart from boreholes, groundwater is accessed from the aquifer through springs, dug wells, and water distribution networks, among other ways.
According to the Nile Basin Initiative, groundwater is one of the most important sources of drinking water for people, livestock, and wildlife watering in the Nile Basin, with more than 70 percent of the region’s rural population depending on it.
The Entebbe–based organization also highlights increasing groundwater usage for other economic activities, including irrigation, agriculture, mining, and industries.
“Groundwater holds the promise of closing the growing gap between water demand and water supply as well as buffering the effects of climate change and variability in the Nile Basin,” notes NBI in a report.
One such aquifer in East Africa is the Kagera aquifer, which serves Uganda’s southwestern districts, Isingiro, Ntungamo, Kabale, and Rakai. Other countries that share this 5,778 square kilometer aquifer are Burundi, Tanzania and Rwanda.
At least 580,000 people live on top of the Kagera aquifer, which has a high population density of more than 100 people per square kilometer, according to data from the International Groundwater Resources Assessment Centre and UNESCO Intergovernmental Hydrological Programme, 2016.
To support the Kagera Basin countries in their efforts towards the sustainable use and management of the Kagera aquifer, NBI is currently implementing a project to strengthen the knowledge base, capacity, and cross-border institutional mechanisms, according to Dr. Maha Abdelrahim, the UNDP/GEF Groundwater Project Team Leader at the Nile Basin Initiative Secretariat.
She narrates that the project also targets two other aquifers, namely the Mt. Elgon aquifer shared between Kenya and Uganda and the Gedaref-Adigrat aquifer shared by Ethiopia and Sudan. The aquifers are in diverse ecological zones ranging between arid, semi-arid and tropical.
The USD $5.3 million project – ‘Enhancing Conjunctive Management of Surface Water and Groundwater Resources in Selected Transboundary Aquifers,’ will further build and expand on the understanding of groundwater resources through detailed mapping and assessment of the three aquifer systems.
Dr. Maha Abdelrahim further says the project will also aid the national achievements and reporting of water-related Sustainable Development Goals and support environmental protection while enhancing the socio-economic development of the Basin’s population.
The five-year (2020 – 2025) project is funded by the Global Environment Facility (GEF), implemented by United Nations Development Program (UNDP), and executed by NBI.
How lakes and rivers Recharge Groundwater
According to the Nile Basin Initiative (NBI), the interaction between groundwater and surface water systems (rivers, wetlands, lakes) is poorly understood and has not been adequately considered in the Basin. Surface water collects above the land. It is found in streams, ponds, lakes, rivers, floodwater, and runoff. On the other hand, groundwater is located beneath the earth’s surface. The two systems usually re-charge each other. Surface water recharges underground aquifers when it seeps into the ground. Similarly, when underground water discharges to the surface, it recharges surface water.
Not all groundwater is renewable. Some groundwater, deposited by fossils, does not recharge after it is extracted. However, a good amount is renewable, and therefore is a sustainable source of water for humans – if the environment is protected.
According to NBI, surface water systems, especially forests and wetlands, play an essential role in sustaining water quality and quantity, providing a storage medium for water, and supporting complex ecosystem niches of economic and environmental importance.
The NBI says studies have shown that groundwater availability (or depletion of it) in the region strongly bears on poverty, migration, conflict, school attendance, and human health.
According to Uganda’s commissioner for water resources, planning, and regulation, Dr. Callist Tindimugaya, “groundwater and surface water in some situations are interrelated. There are periods when water in river Kagera is flowing into groundwater.”
But James Byaruhanga, a resident of Omundizi in the Isingiro district of Uganda, says not many rural communities that interact with the environment daily know about this. He highlights the importance of raising awareness about groundwater.
A solution to water shortage:
Approaching SDG 6
"You need to sensitize the local communities on how to protect and regenerate groundwater; otherwise, they do not know."
As surface water sources dry up or are affected by climate change, groundwater has the potential to provide years of clean water for people in Africa and Asia, according to a 2022 report by the British Geological Survey and WaterAid.
Since the water is underground, it is more resilient to extreme weather and the changing climate. It is also more protected from pollution and does not evaporate.
However, the majority of this water source is untapped. The Kagera aquifer countries of Rwanda, Burundi, Uganda and Tanzania are currently only using between 1-25 percent of their renewable groundwater per year, according to the WaterAid report.
In Burundi, the government established the Agence Burundaise de l’Hydraulique et de l’Assainissement en Milieu Rural (AHAMR) (the Burundian Agency for Hydraulics and Sanitation in Rural Areas) project, in 2015 to cope with the glaring shortage of clean water in many parts of the country.
The project drills groundwater and supplies it to communities through water pipes. It has established various water supply points across rural Kirundo province in the north of the country, especially in all zones of the Bugabira commune. This was one of the most water-stressed areas in the country, with only 15 percent of the population having access to safe water before the project.Appolinaire Sindahebura, the General Director of this agency, says many people in this commune now have access to safe water. The project targets all communes in the country to have access to clean water within an estimated distance of 500 meters from each household by 2025.
Charles Mbindi, a beneficiary of the AHAMR project in Muyinga province in the Gasorwe zone, says they are now finding life easier than in the pre-project days.
“Access to safe water enables us to live a good life,” he observes.
He is particularly delighted that since the arrival of the taps, their children dress in clean clothes and no longer suffer from intestinal worms.
“Having this tap in our village is a great advantage to our families. We are doing all it takes to protect it,” notes Mbidi.
A resident of Nyamabuye village, Renate Manirakiza, says they used to trek for more than two hours to fetch water from unclean sources, but this is no more.
“It has eased our domestic chores like cooking and laundry,” she says.
According to the Buye Zone Representative Joseph Rugonumugabo, all households in his village now have access to safe water. “The water is sufficient in our locality,” he says.
In neighboring Rwanda, by 2016, the government and its partners had dug up more than 5,600 wells and boreholes to take advantage of groundwater.
In January 2018, China and Rwanda signed a USD $32 million deal to dig up more than 250 hand pump and solar-powered boreholes, mainly in eastern Rwanda. The project also involved establishing a training program at TVET colleges to increase local knowledge of the latest borehole drilling technologies and manage existing infrastructure.
The solar-powered boreholes are a recent phenomenon in Rwanda. They extract water effortlessly from the underground, reducing congestion at water spots and making it easy for women and children to access.
The other major use for groundwater in eastern Rwanda is as a source of supply to the vast Kanzenze Water Treatment Plant that is meant to provide piped water to parts of Kigali and the fast-growing Bugesera district, where a new multimillion-dollar Bugesera International Airport is currently under construction.
Inaugurated in February last year, the water plant was designed to extract groundwater from the southern bank of River Nyabarongo. Some 30,000 cubic meters per day of water is supplied to the City of Kigali and 10,000 cubic meters a day to Bugesera District.
This eastern part of Rwanda had been a vacant land for decades before the government turned it into the country’s breadbasket through irrigation.
Farmers take advantage of groundwater to irrigate their crops. They build unsaturated zones between drains by piling up excavated soil. When groundwater levels drop during the dry season, farmers construct soil check dams in gutters to maintain groundwater levels at crop root zones.
When groundwater is not sufficient, farmers build barriers made of wood across main streams to divert water into earthen canal networks.
Following the national irrigation master plan development in 2010, the Rwanda government has implemented additional irrigation projects, mainly in the eastern part and other regions using hillside irrigation.
With these projects, the Rwandan government set its target to develop 40,000 hectares of irrigated land by 2017 and 100,000 hectares by 2020. As of June 2018, some 52,936 hectares had been developed, according to the Rwanda Agriculture and Animal Resources Development Board (RAB).
According to Audece Hirwa, a communication specialist at Rwanda Agriculture Board, the total area of land currently under irrigation is 67,100 hectares, which consists of 37,273 hectares of swamps, 9,439 hectares of hills and 20,388 hectares of irrigation technology on a small scale. Small-scale technologies developed include solar irrigation and mobile agricultural irrigation system equipment and pumps.
By 2024, Rwanda aims to develop 102,284 hectares of irrigated land. These systems use surface and groundwater sources, including lakes, rivers, wetlands, or water reservoirs of various sizes: small, medium, or large dams.
Collette Nyiransabimana lived a poor life for many years due to a prolonged drought that hit her home area of Munini cell, Mahama sector in Kirehe district, leaving her family destitute and hungry. She says she could hardly manage to feed her four children despite the efforts she could put in to grow crops on her small land.
“We used to grow sorghum and beans, but the harvest was mediocre; sometimes we could harvest almost nothing due to the long dry spells,” she says.
However, the situation changed when she and other farmers embraced irrigation using water from the Akagera River after a mobilization drive by local leaders.
“For many years, we used to see the river as a threat, fearing we could drown in it. Little did we know that the water from the river could be a source of much-needed income when they used it in irrigation,” Nyiransabimana says, adding that crop yields have increased with irrigation.
Jean-Paul Nzabonimpa, also from the Mahama sector, says he practices modern agriculture using a generator to pump water from the Akagera River. He said last season, he harvested crops that he sold for Rwf 2.5 million (about USD $2,500).
“I practice irrigation using generators, which has changed my life; I employ casual workers to plant and irrigate. We are grateful that the Akagera river is no longer a threat to us but serves as a source of water for us to irrigate,” he says.
According to Nzobanimpa, farmers in the area no longer worry about the drought that used to hit the area, causing much suffering.
"I practice irrigation using generators, which has changed my life; I employ casual workers to plant and irrigate. We are grateful that the Akagera river is no longer a threat to us but serves as a source of water for us to irrigate."
In Tanzania, the Lake Victoria Basin Water Board Director, Dr. Renatus Shinhu, says environmental degradation in the Kagera Basin has led to the drying up of several surface water sources, such as springs, especially along the river. He says the most affected districts are Ngara, Kyerwa, Misenyi, and Karagwe.
Dr. Shinhu discloses that these communities have now turned to groundwater as their primary water source for domestic use. “Up to 66 wells have been drilled to provide water to communities that have long struggled with water shortages in this area,” he further revealed.
Dr. Shinhu discloses that these communities have now turned to groundwater as their primary water source for domestic use. “Up to 66 wells have been drilled to provide water to communities that have long struggled with water shortages in this area,” he further revealed.
protect the Environment to secure groundwater
Even without recharging, most countries in the Nile Basin have more than 50 years of reserves of potentially usable groundwater – making this little-known water source an important “buffer” against climate change and droughts, according to the
WaterAid report. But this buffer is less in the Kagera Aquifer region. Assuming there is no active recharge of the underground water, Uganda and Burundi are estimated to have between 5-10 years of potentially usable groundwater, while Rwanda has less than 5 years. This is because Uganda, Burundi and Rwanda have large populations living on relatively low storage aquifers, according to WaterAid.The Global Groundwater Information System created by the International Groundwater Resources Assessment Centre (IGRAC) monitors the sharing of groundwater data and information worldwide. According to this geo-portal, the Kagera aquifer has a low groundwater recharge rate of 2-20 millimeters per year, and its renewable groundwater resources per capita are marked as “very low.”
The quality of the water, however, is classified as very high, the highest rating – demonstrating the importance of groundwater as a source of clean water for the region’s population.
According to the Nile Basin Initiative (NBI), this groundwater resource is being threatened by several factors, including climate change and environmental degradation. Under the IGRAC data portal, the aquifer’s vulnerability to climate change is classified as high, while its vulnerability to pollution is deemed moderate.
Without solid transboundary laws to regulate groundwater extraction, this very important alternative water source may also get depleted in the long run.
Uganda’s commissioner for water resources, planning, and regulation, Dr. Callist Tindimugaya, says pressure on the Kagera aquifer, through overexploitation and pollution, is already felt in the region.
For example, in Uganda’s Ntungamo district in the southwest, communities have converted wetlands into farmlands and settlements, impacting the water table, according to Muchunguzi Sam, the Ntungamo district chairperson. Wetlands trap runoff water, enabling it to sink into soil layers to form groundwater. But when they are degraded, runoff keeps flowing. Some is lost through evaporation. The remaining may flow down valleys to streams, rivers and lakes.
The Ntungamo district water officer Tumushangye Tom says some communities where the closest level of groundwater is close to the surface have planted eucalyptus tree species that dry the water sources and catchment areas. Most eucalyptus species have long taproots that sink deep into the soil layers, sucking groundwater from the aquifers.
In several parts of Uganda, Rwanda, Burundi, and Tanzania, the increasing population, coupled with climate change, are straining the available water resources. The remaining option is groundwater.
Jennifer Twasiima, a farmer from the Buhara sub-county, says vegetation cover was cleared in most parts of her community in Uganda’s Kabale district. This left nothing to trap surface water runoff, which is now lost to the valley bottoms, lakes, and streams. This gives no opportunity for the underground aquifer to recharge.
Milton Kwesiga, a Kabale-based environmentalist and the executive director of Africa Disaster Reduction Research Emergency Missions (ADREEM), also based in Kabale, says most watersheds in the district have been encroached on by farmers and constructions. This, he says, is a result of the increasing population in the district.
In Rakai, human activities there are threatening the existence of the Kagera aquifer. Jamil Kiyingi, the Kyotera Natural Resources Officer, affirms that there is persistent land degradation in the Kagera River Basin, accompanied by severe loss of biodiversity, which impacts the agro-ecosystems.
“Human activities like farming, wetland reclamation, and over-cultivation are an existential threat to River Kagera,” he notes.
Muhweza village in Tanzania has seen several streams and shallow wells dry up. "That is why our village has set up a system to have water resources management committees, where I am a committee accountant. We have to protect the available water sources and coordinate water use."
Nyamgali blames the drying up of their water sources on “deforestation, cultivation very close to water springs and grazing within valleys.”
According to central and local government officials, Rwanda’s lower corridor has experienced a population explosion composed of post-1994 Rwanda genocide returnees and people from other regions. The resultant impact has been an increasing need for water, yet it already has very negligible amounts of surface water.
a need for uniform laws and collaborative governance
Along with environmental degradation, there is also a challenge of poor construction and management of the groundwater infrastructure, by governments, local authorities and individuals.
According to a 2016 survey conducted in 112 districts in Uganda by UPGro, a 7-year research project by the International Groundwater Resources Assessment Center, only 55 percent of boreholes with hand pumps were working on the day of the survey. Only 18 percent of the hand pumps surveyed passed the design yield, reliability, and water quality criteria.This is despite the fact that around 75 percent of all towns and cities in the country are depending on groundwater – specifically 73 of the 98 operational water supply systems in Uganda, according to UPGro in 2020.
The UPGro research project, which was jointly funded by UK’s Department for International Development (DFID), Natural Environment Research Council (NERC) and the Economic and Social Research Council (ESRC), recommends increased investment by the government in siting and testing boreholes, providing repairs and maintenance, and accessing services at the local level. Overlapping roles and responsibilities by different agencies also need to be addressed.
Tanzania’s Professor Faustin Kamzora, the Kagera Regional Administrative Secretary in Tanzania, calls for uniform laws and collaborative governance to safeguard water sources, including surface and groundwater reservoirs in the shared Kagera River Basin. He says the system could include uniform regulations among all the Kagera basin countries on agriculture in water catchments, uniform distance between human activities and the water source or river, protection of aquifers, and creation of water catchment boundaries, sanitation, and sewerage management.
"Our people are the same; they have the same cultures, traditions, and customs; even the use of environmental resources is the same. If we all agree to have a single system of environmental management, especially water resources, we will achieve great success instead of each country having its system."
Integrated systems that are localized and co-managed by communities can also reduce human pollution of groundwater from fertilisers, pesticides and sewage.
There are also natural sources of pollution, including arsenic and fluoride, that are prevalent in volcanic areas and can cause crippling health problems. Groundwater in northern Tanzania is particularly vulnerable to these pollutants, according to a 2021 study on groundwater resources in the East African rift valley by researchers at the University of Dar es Salaam and others.
To identify and manage pollutants, the region should develop a groundwater database that includes parameters on water quality, and invest in low-cost and environmental water purification technologies, the researchers from the University of Dar es Salaam, KTH Royal Institute of Technology, and others concluded.
It was also recommended that community members take charge of managing their water resources through Water User Associations and other community-led groups.
The Kagera region of Tanzania has heightened such efforts to protect water sources, including groundwater aquifers. A case in point is in Ngara district, where authorities have prioritized tree planting and the protection of water catchment areas.
Engineer Simon Ndyamkama, the Manager of Rural and Urban Water and Sanitation Authority (RUWASA) in Ngara district, says this has proved helpful in safeguarding surface and groundwater sources.
“We plant friendly trees at water sources and establish boundaries so that human activities do not occur inside water catchment areas,” narrates Engineer Ndyamkama.
Ngara district enacted a sanitation by-law in 2014, enabling the promotion of sanitation and hygiene as well as the conservation of the environment. Under this law, people, especially those living in commercial areas, contribute a small amount of money per month (1,000 Tanzanian shillings (about USD $0.42) for households and 1,500 shillings (USD $0.63) per business entity. This money is used to support environmental conservation initiatives.
As the local government authorities, individuals also take active roles in protecting their water sources.
One such individual is Joyce Katabaro, a resident of Kayanga Karagwe, Tanzania.
“As a woman who recognizes the importance of water sources, I make sure they are not degraded. When I find out someone is destroying a source, I report them to the village leaders so that legal action can be taken against them,” discloses Katabaro.
Uganda’s commissioner for water resources, planning, and regulation, Dr. Callist Tindimugaya, calls for investment in studying and understanding the Kagera aquifer.
“The challenge we have in Uganda, in the region, and the Nile Basin, [is that] we haven’t done enough studies to understand these underground aquifers,” notes Tindimugaya.
“Let us restore the wetlands. Let us plant trees. Let us harvest water. In Rwanda, for example, they are creating terraces even in southwestern Uganda. This will improve the availability of groundwater but will also be controlling the flooding of Kagera and ensure that the water in Kagera does not change too much,” notes Dr. Tindimugaya.
