Ministerial body goes underground in search for water solution amid climate change

by Isaiah Esipisu for PAMACC News Agency

KAMPALA, Uganda (PAMACC News) – As climatic conditions continue to disrupt normal rainfall patterns, drying up rivers and streams, the African Ministers’ Council on Water is now seeking to understand groundwater, following numerous studies that have shown that it is key to building resilience.

“The volume of groundwater in Africa is estimated at 0.66 million km3, which is more than 100 times the annual renewable freshwater resources, but since it is hidden underground, it remains under-valued and underutilized,” said Dr Paul Orengoh, the Director of Programs at African Ministers Council on Water (AMCOW).

This comes after a recent study led by scientists from University College London (UCL)and published in the Nature Journal suggested that groundwater in the Sub Saharan Africa region was resilient to extreme climate conditions, making it a key resource for climate change adaptation.

To examine how groundwater is replenished, Prof Richard Taylor of UCL together with several other scientists from different institutions abroad and in collaboration with their counterparts in Africa examined how different aquifers behaved with different rainfall patterns.

“Our results suggest that the intense rainfall brought about by global warming strongly favours the renewal of groundwater resources,” said Prof Taylor noting that over half the world’s population is predicted to live in the tropics by 2050, and therefore dependence on groundwater as a resource will continue to rise.

And now, AMCOW has formed an initiative that will help member states understand their water resources, manage it sustainable, and use it for poverty alleviation in their respective countries.

“The AMCOW Pan-African Groundwater Programme shortened as APAGroP seeks to improve the policy and practice of groundwater in Africa for better lives and livelihoods in all the 55 member countries,” said Orengoh.

Studies have shown that at least 320 million people in Africa lack access to safe water supplies, and therefore developing groundwater resources sustainably, according to experts, is a realistic way of meeting this need across Africa.

APAGroP therefore comes in to bridge the knowledge deficits gap around groundwater on the continent.

Through the initiative, AMCOW seeks to support Member States to develop, manage, and utilize water resources to assure water, food and energy security in Africa. “WASH has historically attracted prime attention. Strategy is raising the priority given to water for food, energy and industrial production,” said Orengoh.

Speaking at the recently concluded African Water Association (AfWA) Congress in Kampala Uganda, Dr Callist Tindimugaya, the Commissioner for Water Resources Planning and Regulation Ministry of Water and Environment in Uganda said that there is need to to support and implement APAGrop- from transboundary to local scale.

“APAGrop should have a strong link with all Regional Economic Communities, River Basin Organisations and member states for easy implementation,” he said. “These regional organisations and member states can contribute through actual implementation on the ground, capacity building, resource mobilization, and advocacy,” noted Dr Tindimugaya.

Apart from regional platforms and member states, AMCOW seeks to work in close collaboration with consumptive sectors, which include agriculture, water supply, industry, among others through appropriate platforms.
Others are research-to-use organizations and associations such as the International Association of Hydrogeologists (IAH), Civil Society Organisations, the private sector and international bodies and organisations.

“By the end of the day, we expect to have increased knowledge base on groundwater resources, strengthened groundwater networks, strengthened capacity for groundwater development and management across all member states, and strengthened multi-purpose and sustainable use of groundwater to enhance water and food security and climate resilience,” said Dr Orengoh.

Groundwater Science meets Policy at AfWA Congress

Day 2 of the AfWA Congress in Kampala, and the UPGro-convened stream of groundwater sessions got underway. First up was  session focusing on the AMCOW Pan-African Groundwater Program (APAGroP), with an opening by AMCOW Executive Secretary, Dr Canisius Kanangire, followed by a panel, featuring Tim Sumner from DFID

This was followed by two further sessions with lively presentations and Q&A on UPGro research from GroFutures and T-GroUP. Tomorrow, further sessions will include presentations from UPGro researchers and other close groundwater partners, including BGR.  These few days have been a culmination of many years work to bring UPGro researchers close to others working on African groundwater and to policy makers at the continental and national levels.

Afterwards, Isaiah Esipisu caught up with Dr Paul Orengoh who explained the aims and progress of APAGRoP:

(Photos; Isaiah Esipisu/Kirsty Upton)

Groundwater – a hidden resource that has always evaded UN climate talks

By Isaiah Esipisu

A new study that was recently published in the Nature scientific journal shows that groundwater is one of the most climate resilient natural resources especially for the African continent. This is contrary to the earlier understanding by the Intergovernmental Panel on Climate Change (IPCC)’s Fifth Assessment Report , that groundwater was susceptible to climate change in dryland areas.

Though it has not been a subject for major discussions at the 2019 UN Conference of Parties (COP25) on climate change in Madrid, experts believe that groundwater will be at the centre of climate adaptation particularly for African countries.

Richard Taylor, a Professor of Hydrogeology from University College London (UCL) and one of the lead researchers of the Nature study explained why groundwater should be a focal point for climate discussions.

IE: How important is groundwater to climate change adaptation especially in Africa?

RT: Groundwater plays a fundamental role in enabling communities in Africa to adapt to climate change. As our world warms, rainfall becomes less frequent but more intensive resulting in longer droughts and worsening floods – changes that occur most strongly in the tropics.

Adapting to this greater variability in water resources relies on the ability to draw water from stores such as groundwater or to store water in dams for example.

Groundwater, which comprises 99 percent of the Earth’s liquid water, amounts to more than 100 times that of annual river discharge in Africa.

For cities in Africa that have recently experienced severe droughts such as Cape Town and Dar es Salaam, groundwater has played a critical role in enabling residents in those cities to adapt to water scarcity.

Less frequent rainfalls also reduce crop yields. Increasing cropland irrigation is a critical strategy to improve food security in Africa under climate change. As smallholder farmers account for the vast majority of food production in Sub-Saharan Africa, distributed groundwater supplies are often the most cost-effective and sustainable sources of water for irrigation.

IE: How resilient or vulnerable is groundwater to climate change?

RT: Groundwater resources are generally resilient to climate change. Recent evidence from a pan-African study shows that replenishment of groundwater occurs preferentially from heavy rainfalls so that changes in rainfall brought about by climate change favour groundwater replenishment. Alas, these same changes in rainfall reduce soil moisture and lead to greater and more frequent flood events.

IE: Why do you think this subject has not been able to attract the attention of climate change negotiators for the past 25 years of negotiation?

That is a good question. Groundwater is often called the hidden or invisible resource as it lies unseen beneath our feet. Limited understanding of groundwater by both policy makers and engineers means that it is often considered mysterious or unknowable.

The impact of climate change on groundwater resources has been largely ignored by the climate change community until last year when it was captured in the IPCC Fifth Assessment Report.

This is surprising in light of the critical role groundwater plays in sustaining rivers, lakes and other aquatic ecosystems during low or absent rainfall.

IE: What do you think should be done to bring the groundwater subject to the helm of climate negotiations?

RT: There is need for raising awareness of the critical role of groundwater to improving the resilience of water and food systems in Africa in relation to climate change.

It is in that regard that scientists from different parts of the world are issuing a Call to Action this week, through a statement published in the Nature journal, which argue that we are not doing enough to protect and manage global groundwater resources, which will have long-term effects on the planet’s drinking water, food production, and adaptation to a rapidly changing climate.

This statement focuses on the global role of groundwater in relation to the 2030 Agenda for Sustainable Development, the Paris Agreement on Climate Change, the Framework for Action on Groundwater Governance, and the Sendai Framework for Disaster Risk Reduction.

It builds on previous important declarations and statements, including the Valencia declaration on Intensive Groundwater Use (2002), the Kampala statement on Groundwater and Climate in Africa (2008), ISMAR9 call to Action on Sustainable Groundwater Management Policy Directives (2016).

This call has so far been endorsed by over 700 scientists and practitioners in over 80 countries and is timed to coincide with the United Nations (UN) Climate Change Conference in Madrid (COP 25) and the beginning of the Decade of Action on the UN Agenda 2030.

IE: What kind of policies should African governments put in place in order to ensure sustainable use of groundwater?

RT: African governments could do two things. One, they could increase investment in understanding their groundwater resources through the training of staff and the monitoring and evaluation of their groundwater resources.

Two, they could integrate groundwater into its evaluation and governance of water resources more holistically that is currently dominated by concern for surface waters.

In light of the central importance of groundwater to adaptation to climate change, African governments could use support under the Green Climate Fund to finance the implications of these policy recommendations.

Photo: Richard Taylor, UCL

Trickle-down effect: why groundwater recharge processes matter for climate resilience

by Sean Furey (Skat/UPGro Knowledge Broker) in GeoDrilling International

Drilling for water is only useful if there is good water to be had now and into the future. Since 2013, researchers in the UK-funded programme Unlocking the Potential of Groundwater for the Poor, have been working all over Africa to understand better the continent’s aquifers and how their hidden wealth can be used to benefit everyone. Now after years of patient work, exciting results and resources are emerging.

One is that the Africa Groundwater Atlas, curated by the British Geological Survey now has downloadable GIS maps for 38 countries. They are quite large scale, so not detailed enough for individual borehole siting, but a good starting point for identifying where major aquifers are. This supports the wealth of other useful information, in English and French, on the soils, climate and groundwater use in all 52 of Africa’s countries.

Continue reading Trickle-down effect: why groundwater recharge processes matter for climate resilience

Importance of groundwater stressed at climate conference

by Isaiah Esipisu via PAMACC

ADDIS ABABA, Ethiopia (PAMACC News) – Delegates at the Africa Climate Risks Conference have been informed that groundwater is more resilient to extreme climatic conditions especially in arid and semi arid areas, contrary to earlier beliefs – that the resource was vulnerable to the changing climatic conditions.

“Through a project known as Groundwater Futures in Africa, we analysed the relationship between climate change and variability and groundwater in 14 sites in Africa,” Martin Todd, a Professor of Climate Change at the University of Sussex, Department of Geography.

“What we found is that in arid regions, there was episodic recharge, which occur mainly as a result of intense storms that happen every few years, and sometimes even in years of low total precipitation,” said

This, according to the scientist, it means that climate plays a dominant role in controlling the process by which groundwater is restocked.

Generally, it means that extreme periodic flooding is what recharges aquifers in such arid and semi arid areas, providing a lifeline and livelihoods for people who depend on groundwater in such areas.

The findings, which have since been published in the Nature scientific journal contradicts the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), which states that ‘climate change over the twenty-first century is projected to reduce renewable surface water and groundwater resources significantly in most dry subtropical regions, intensifying competition for water among sectors.’

According to Prof Todd, groundwater is generally overlooked in terms of climate impact, and it is also an overlooked resource in Africa and underutilised compared to other continents.

“With the rapid population growth and quest for development, there is going to be huge demand on water resources, and therefore we expect that groundwater is a resource that will be heavily developed in the future because climate change and variability is going to place increasing threat to surface water,” he said.

The new findings from the study, which was supported by the United Kingdom research councils (Natural Environment Research Council, Economic and Social Research Council and the Engineering and Physical Sciences Research Council), the Department for International Development (DFID) and The Royal Society also highlight the need for improvements in models of climate and hydrology.

The report indicates that climate models that can better predict the variability and intensity of precipitation events at the local scale, as well as the large scale, would allow hydrological models to better represent replenishment processes.

Given a fact that extreme floods can be predicted up to nine months in advance, the researchers say that there is a possibility of designing schemes to enhance groundwater recharge by capturing a portion of flood discharges via a process known as Managed Aquifer Recharge.

According to the British Geological survey, successful and sustainable development of groundwater resources in Africa is critical for future safe water supplies, economic growth and food security in the continent.

The findings have come at a time several cities across the continent are beginning to exploit the groundwater, which has for long been considered a hidden resource.

So far, groundwater plays a central role in sustaining water supplies and livelihoods in sub-Saharan Africa due to its widespread availability, generally high quality, and intrinsic ability to buffer episodes of drought and increasing climate variability.

Given the drying rivers and streams, and unpredictable rainfall patterns, groundwater is likely going to be a golden resource in Africa’s rural communities both for domestic consumption and irrigation.

Photo: Isaiah Esipisu

 

“Groundwater levels in nine African countries raise hopes for a more resilient future” Geographical Magazine

UPGro Grofutures /Cardiff University work is featured in this month’s print and online version of Geographical Magazine, the popular science magazine of the Royal Geographical Society (with IBG), in London.

Humans take the water we need, be it for drinking or irrigation, from one of two sources: surface water, contained in lakes, rivers and reservoirs; and groundwater, in which water flows through porous rocks beneath the ground. In the UK, how much we rely on the latter depends on where we live and the type of rock which makes up the land (not at all in Scotland; quite a bit in London, where groundwater is rising in parts). But in much of sub-Saharan Africa, groundwater is a vital resource. It is often the only source of clean drinking water in rural areas and its use is also increasing in cities. Working out how groundwater levels will react to climate change is therefore vital.

Read on here

Different perspectives on ways to make a living from groundwater, in Tanzania and Ethiopia

Lessons from the GroFutures Multi-stakeholder Workshops in the Great Ruaha Basin, Tanzania, and Upper Awash Basin, Ethiopia

by John Thompson, Imogen Bellwood-Howard, Gebrehaweria, Gebregziabher, Mohammad Shamsudduha, Richard Taylor, Devotha Kilave, Andrew Tarimo and         Japhet Kashaigili

Identifying and characterising groundwater development pathways

More than four years ago, an international group of collaborators embarked on a comparative study of ‘Groundwater Futures in Sub-Saharan Africa’ (GroFutures – http://grofutures.org/) in three ‘basin observatories’, the Great Ruaha in Tanzania, the Upper Awash in Ethiopia, and the Iullummeden in Niger and Nigeria. One key aim of the project was to identify a range of existing, emerging and potential ‘groundwater development pathways’ in each basin.

This work linked interdisciplinary, multi-scale research with a deliberative, multi-stakeholder engagement process in order to inform groundwater planning processes in the basins. Attempts were made to co-locate physical infrastructure to assess groundwater recharge and storage (i.e. piezometer arrays, soil-moisture probes, rain gauges) with key stakeholder communities where the social science was conducted (i.e. household surveys, rapid rural appraisals, well inventories) (Figure 1). The ultimate aim of GroFutures is to generate new evidence and policy relevant insights to open up new pathways towards more sustainable and ‘pro-poor’ groundwater futures in the wider region.

Figure 1. Characterising Groundwater Development Pathway

Slide1

Six groundwater development pathways by the GroFutures Social Science Team during the course of the research. These ‘stylised’ pathways are representative of broader trends found in the three basin observatories. Each has been characterised in terms of its socio-economic functions; physical dimensions; stage of development; technology; ownership, management and governance arrangements; legal aspects of land and water access; alignment with national policy; and – importantly – its implications for poor water users (a key consideration of the project).

To analyse the longer-term sustainability of groundwater in the basins, the GroFutures Physical Science Team attempted to ‘stress test’ or quantify the impacts of groundwater development pathways, together with the impacts of climate and land-use change, on groundwater recharge and storage in each basin. Employing a groundwater flow model using MODFLOW-2005, run via using the open-source, GIS-based interface (QGIS) that has been developed as part of the newly available FREEWAT platform under a HORIZON 2020 project, the team assessed the hydraulic impacts of pumping under a range of boundary conditions, including variable recharge, over different time scales. These impacts were represented in a set of maps for selected sub-basins in which our social science and physical science teams collected detailed primary hydrogeological and socio-technical data and also drew on relevant secondary information.

A simplified sketch was also prepared to provide a visual representation of each pathway. A key assumption is that these pathways may well co-exist over time and meet the needs of different users. However, there may be cases where there is serious competition and trade-offs between them, leading to positive and negative impacts for different water users and for the environment.

The six pathways and the summary of the modelling ‘stress testing’ for the Great Ruaha and Upper Awash Basins are outlined below. The maps below show the ‘baseline’ groundwater level for each of these, without any pumping. For each pathway, a possible arrangement of wells is suggested, which extract specified volumes at specified depths. The pumping in each pathway gives a new groundwater level, lower than the baseline, projected five years into the future. How much lower depends on the amount of pumping. The new groundwater level for each pathway, can be compared to this baseline. The diagrams and maps presented here come from the pathways described for the Upper Awash. The first five pathways affect the shallow aquifer, while the large-scale commercial agriculture pathway influences the deeper Upper Basaltic Aquifer.

Pathway 1: Small-scale, self-supply for multiple uses

Slide2

Tanzania: Evident now in this basin

The impact of this pathway on the water table is minimal: groundwater levels fall less than 2 metres over the entire study area with a decline of less than 1 metre over half of the study area. This pumping is not expected to impact the area covered by wetlands or their operation.

Ethiopia: Evident now in this basin

The impact of this pathway on the water table is minimal: groundwater levels fall less than 2 metres over the entire study area with a decline of less than 1 metre over ~70% of the study area. This pumping from shallow wells (<80 m below ground level) is not expected to impact baseflow to streams.

Pathway 2: Small-scale private supply for smallholder intensified agriculture

Slide3

Tanzania:  Not evident yet though promoted in policy

The impact of this pathway on the water table is moderate: groundwater levels decline up to 4 metres over approximately 40% of the study area with declines of less than 3 metres in 60% of the study area. This pumping may locally impact the yields and operation of shallow wells; the impact on wetland extent or operation is not expected to be substantial.

Ethiopia: Evident now in this basin

The impact of this pathway on the water table is moderate: groundwater levels decline 2 – 3 metres over approximately 25% of the study area with declines of less than 2 metres in 65% of the study area. This pumping from shallow wells (<80 m below ground level) may locally impact yields and operation of shallow wells; the impact on baseflow to streams is not expected to be substantial.

Pathway 3: Medium-scale municipal supply for multiple uses

Slide4

Tanzania: Evident now in this basin

The impact of this pathway on the water table is moderate: groundwater levels decline less than 3 metres over the entire study with declines of less than 2 metres over half of the study area. This pumping may locally impact the yields and operation of shallow wells; the impact on wetland extent or operation is expected to be minimal.

Ethiopia: Evident now in this basin

The impact of this pathway on the water table is moderate: groundwater levels decline less than 3 metres over the entire study with declines of less than 2 metres over 70% of the study area. This pumping from shallow wells (<80 m below ground level) may locally impact the yields and operation of shallow wells; the impact on baseflow to streams is expected to be minimal.

Pathway 4: Medium-scale private supply for commercial agriculture

Slide5

 Tanzania: Not yet evident in this basin

The impact of this pathway on the water table is moderate: groundwater levels fall up to 4 metres in approximately 40% of the study area with declines of less than 3 metres in 60% of the study area. This pumping may locally impact the yields and operation of some shallow wells; the impact on wetland extent or operation is expected to be minimal.

Ethiopia: Evident now in this basin

The impact of this pathway on the water table is substantial: groundwater levels decline between three and five metres over approximately 28% of the study area with declines of less than 3 metres in 60% of the study area. This pumping from shallow wells (<80 m below ground level) is expected to impact yields and operation of some shallow wells as well as baseflow to streams.

Pathway 5: Medium-scale private supply for livestock husbandry

Slide6

Tanzania: Not yet evident in this basin

The impact of this pathway on the water table is moderate: groundwater levels fall up to 4 metres in approximately 40% of the study area with declines of less than 3 metres in 60% of the study area. This pumping may locally impact the yields and operation of some shallow wells; the impact on wetland extent or operation is expected to be minimal.

Ethiopia: Not yet evident in this basin

The impact of this pathway on the water table is substantial: groundwater levels decline between 3 and 5 metres over approximately 28% of the study area with declines of less than 3 metres in 60% of the study area. This pumping from shallow wells (<80 m below ground level) is expected to impact locally the yields and operation of some shallow wells as well as baseflow to streams.

Pathway 6: Large-scale private supply for commercial agriculture

Slide7

 Tanzania: Not evident yet

The impact of this pathway on the water table is substantial: groundwater levels fall 4 to 6 metres in approximately half of the study area. This intensive pumping of groundwater would impact the yields and operation of shallow wells; intensive pumping would also reduce the supply of water to wetlands impacting the extent and functioning of wetlands and related ecosystem services.

Ethiopia: Evident now in this basin

The impact of this pathway on the water table is very substantial: groundwater levels decline by more than 5 metres over approximately 27% of the study area with declines of 3 – 5 metres over 55% of the study area. This intensive, dry-season pumping of groundwater from deep wells (180 to 300 m below ground level) would impact the yields and operation of deep wells.

 Analysing the Stress-Tested Pathways

In June and July 2019, colleagues from Institute of Development Studies (IDS) and the ESRC STEPS Centre, the International Water Management Institute (IWMI) and University College London (UCL), in collaboration with partners at Sokoine University of Agriculture (SUA) and Addis Ababa University (AAU), hosted two multi-stakeholder workshops at which the groundwater development pathways were assessed using Multicriteria Mapping (MCM) (Figure 2).

Figure 2. Participants at the GroFutures Multi-stakeholder Workshops in Tanzania and Ethiopia

Slide8

MCM is multi-stage interview and engagement approach which helps stakeholders to explain their views and priorities in a structured and systematic way without necessarily identifying a single ‘best’ decision but to highlight underlying criteria that influence people’s perceptions of different options or pathways. The GroFutures team used MCM software developed by the University of Sussex and STEPS Centre with stakeholders representing a range of actor groups from local to basin to national levels with knowledge and interest in groundwater development and management.

In both workshops, the GroFutures team trained a group of Research Assistants recruited through SUA and AAU to serve as MCM facilitators in the workshops. The invited participants represented a range of stakeholder groups – e.g. local domestic water users; local irrigators; district agricultural and water officials; NGO representatives; national agriculture and water officials; private sector representatives; livestock sector representatives (Tanzania). This allowed the team to cluster them into specific interest groups. Each group was assigned one facilitator to assist them in reviewing the six ‘stress-tested’ pathways and analysing them against a core set of criteria provided by the GroFutures Team – i.e. equitable access; environmental sustainability; and ease of operation and maintenance – as well as their own specific criteria.

The groups spent the afternoon of the first day of the workshop defining their criteria and then used the morning of the second day to scoring the pathways against the core criteria and their own additions. For each criterion and pathway, an ‘optimistic’ and ‘pessimistic’ score was given on a scale of 0 (low) to 100 (high). The facilitators encouraged the participants to explain why they used each criterion and scored each pathway as they did.

This information was captured in the MCM software so that we had a clear description of the decision-making behind the scoring. After they completed the scoring, participants were invited to weight their criteria from most to least important, to add further insights into their preferences.

After all participants have done this, the researchers can combine the data from each participant and analyse the whole data set to understand similarities and differences between groups.

Slide9

 

OPINION:- It’s time to look underground for climate resilience in sub-Saharan Africa

Karen G. Villholth is a Principal Researcher with the International Water Management Institute (IWMI) and CGIAR Research Program on Water, Land and Ecosystems (WLE), as well as Coordinator of the Global Groundwater Initiative GRIPP and a team member from UPGro GroFutures

From Thomson Reuters

New research reveals critical groundwater-related climate change impacts and resilience strategies

In 2014-2016, southern Africa saw its worst drought in decades, resulting from the most severe El Niño event in half a century. Leading to sharp declines in crop production, the drought dealt a severe blow to food security, with millions of people across the larger Pacific region facing hunger, poverty and disease.

Nature’s unseen water resource

While we all know groundwater is a key water resource for farmers, small communities and larger cities alike in  sub-Saharan Africa, it is largely missing from existing analysis of climate change impacts on water. Yet, Cape Town, which was greatly supported by groundwater development in its struggle to push back Day Zero when the city was projected to run out of water, shows us that groundwater is key to resilience.

But how does this unseen and relatively untapped resource in sub-Saharan Africa itself react to climate change? This may be the ultimate question as our water resources are finite, increasingly scarce and increasingly in demand. If African countries are to rely on groundwater for future resilience and manage it sustainably, they must quickly gain a better understanding of climate change impacts on this critical resource.

El Niño and extreme rainfall-triggered groundwater replenishment

recent study sheds new light on the climate-groundwater relationship, finding that the 2015-2016 El Niño weather event replenished groundwater very differently in southern Africa and in East Africa just below the equator. Based on a combination of satellite and on-site data analysis, it is part of a growing body of research, to which the International Water Management Institute (IWMI) is contributing, in collaboration with UK partners such as University College LondonCardiff UniversityUniversity of Sussex, and British Geological Survey, as well as others in southern and eastern Africa.

The El Niño-Southern Oscillation, or ENSO phenomenon, involves the interaction between the atmosphere and the ocean in the tropical Pacific. It is a telling cause of climate variability in the tropics. As an extreme case among historical patterns, the 2015-2016 event had exactly opposite effects on rainfall in southern Africa and East Africa below the equator.

In southern Africa, it resulted in the most intense drought ever recorded for the region, estimated to recur every 200 years.

The authors note that warming caused by human activities has heightened climate risks. They suggest that this has already “doubled the risk of such an extreme… event,” meaning such an intense drought could return every 100 years. The 2015-2016 drought limited the recharge of aquifers and increased demand for groundwater leading to a decline in groundwater storage.

In contrast, East Africa, just south of the equator, saw unusually high – but not extreme – rainfall, likely to recur every 10 years. With 100-150% above normal daily rainfall intensity in many places, this significantly boosted groundwater recharge and storage. At the Makutapora well field in Tanzania, for example, strong groundwater recharge reversed a long-term decline in groundwater storage that had resulted from increasingly intensive pumping to the growing city of Dodoma.

Another new study published in Nature underpins the importance of extreme rain events in restocking groundwater in drylands in sub-Saharan Africa. Rather than being replenished through regular rainfall, groundwater responds best to extreme rainfall events – the type that happens every 10 years or so, and is often associated with large scale climate phenomena like ENSO. The research also found that, since groundwater in drylands is recharged where rain accumulates in surface water bodies such as rivers and ponds, replenishment is further accentuated by more intense rainfall events associated with climate change.

Getting the better of climate change

Sub-Saharan countries are rapidly developing their groundwater resources, and these figure importantly in national development plans aimed at supplying cities with drinking water and enabling farmers to intensify production. Whether such plans come to fruition will depend on sustainable management of groundwater. Indeed, water managers need to understand how climate change impacts groundwater under different conditions and how they can best respond.

Techniques referred to as “managed aquifer recharge”, can channel and capture water runoff from intense rainfall events to more quickly and efficiently replenish groundwater. Thus, when climactic events increase rainfall, water managers and users across Africa can use such techniques to boost groundwater supply.

The extreme events can be predicted with some certainty and with seasonal lead times to help farmers and managers prepare. Combined with efficient resource use and safe wastewater reuse, communities and countries can better adapt to the more severe and frequent droughts, as well as floods, that are sure to come. With these approaches and opportunities, we can help harness the climate solutions that lie underground in the drylands in sub-Saharan Africa and beyond.

Extreme Floods, the Key to Climate Change Adaptation in Africa’s Drylands

By Isaiah Esipisu  for the Inter Press Service

Photo: A borehole in Kenya’s Turkana County. Experts say that groundwater in drylands is recharged through extreme floods. Credit: Isaiah Esipisu/IPS

TURKANA COUNTY, Kenya, Aug 8 2019 (IPS) – Extreme rainfall and heavy flooding, often amplified by climate change, causes devastation among communities. But new research published on Aug. 7 in the scientific journal Nature reveals that these dangerous events are extremely significant in recharging groundwater aquifers in drylands across sub-Saharan Africa, making them important for climate change adaptation.

Continue reading Extreme Floods, the Key to Climate Change Adaptation in Africa’s Drylands

“Extreme floods to bring good tidings to Tanzania city” UPGro in The East African

By ISAIAH ESIPISU

Mention of the word El Niño sends shivers to several communities in Africa who live in lowland areas. However, these extreme rainfall phenomena are exactly what Dodoma desperately needs to sustain lives of the speedy growing population in Tanzania’s capital city.

A team of local and international scientists from Sokoine University of Agriculture (SUA) and University College London (UCL) in collaboration with the Ministry of Water and Irrigation including the WamiRuvu Basin Water Board have been studying the Makutapora well-field (the only source of water for Dodoma city) to understand how the groundwater responds to different climatic conditions and human consumption.

“Based on the results, the government will be in a position to make informed decisions on whether to keep abstracting water only from Makutapora or find supplementary sources of water to meet the ever growing demand,” Lister Kongola, retired government hydrologist

“Through our research, we are seeking to understand groundwater resources in Makutapora, the renewability, the sustainability and critically how people use this precious resource,” said Richard Taylor, a professor of hydrogeology at the UCL and the Principal Investigator for a project known as GroFutures.

And after a few years of intensive research, the scientists have discovered that the well-field found in an area mainly characterised by usually seasonal rivers, vegetation such as acacia shrubs, cactus trees, baobab among others that thrive in dryland areas can only be recharged during extreme floods that often destroy agricultural crops and even property.

Dodoma became Tanzania’s capital city in 1974, though the administrative offices remained in Dar Es Salaam. Given a fact that the entire Dodoma region is semi-arid with an average annual rainfall of 550 mm, the current population of about 500,000 residents entirely rely on groundwater from the Makutapora well-field, from which they pump out 61 million litres of water every day, according to government records.

However, since 2016 when President John Pombe Magufuli issued an executive order to relocate all government ministries and institutions as well as diplomatic offices from Dar Es Salaam to Dodoma, the city has become a beehive of activities as people and authorities rush to put in place the right infrastructure to accommodate the expected rise in population.

As a result, the demand for water is expected to rise amid the changing climatic conditions, putting much more pressure on the Makutapora well-field.

“Makutapora is quite a special site, given that it is the longest known groundwater level record in Sub Saharan Africa,” said Prof Taylor. “A study of the well-field over the past 60 years reveals that recharge sustaining the daily pumping of water for use in Dodoma city occurs episodically and depends on heavy seasonal rainfall associated with El Niño Southern Oscillation,” said the professor.

So far, according to the loggers (data registering equipments) installed in several monitoring wells within the Makurapora basin, the water level has been declining since 2016 when the positive recharge was recorded following the 2015-16 El Niño rains.  The scientists attribute the decline to heavy abstraction of the water for domestic use, but also, the researchers are in the process of finding out if tough climatic conditions, changes and variations could be another factor.

“In the end of the year 2015, we installed river stage gauges to record the amount of water in the streams. Through this, we can monitor an hourly resolution of the river flow and how the water flow is linked to groundwater recharge,” said Dr David Seddon, a research scientist from UCL.

According to Lister Kongola, a retired hydrologist who worked for the government from 1977 to 2012, the demand for water in Dodoma has been rising over the years, from 20 million litres in the 1970s, to 30 million in the 80s and to the current 61 million litres per day at the moment.

“With most government offices now relocating from Dar Es Salaam to Dodoma, the establishment of the University of Dodoma and other institutions of higher learning, health institutions, and emergence of several hotels in the city, the demand is likely going to double in the coming few years.

Already, President Magufuli has issued 62 land title deeds for construction of diplomatic missions and five others to accredited global organisations to facilitate the shift from Dar Es Salaam to Dodoma.

“The ongoing study is a stitch in time,” said Kongola. “Based on the results, the government will be in a position to make informed decisions on whether to keep abstracting water only from Makutapora or find supplementary sources of water to meet the ever growing demand,” he said.

One of the alternative options would be to construct dams and also explore alternative sites with reliable aquifers. The other option is to pump water all the way from Lake Victoria which is over 600 kilometres away from Dodoma.

The good news, however, is that seasons with El Niño kind of rainfall are predictable. “By anticipating these events, we can actually amplify them through some very minimal but strategic engineering intervention that might allow us to actually increase the amount of water replenishment in the well-field,” said Prof Taylor.

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