Consortium Project News

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

Posted on 28/11/2019 by RWSN Secretariat

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

Groundwater supplies on Kenya’s coast must be managed for people and industry

Posted on 24/10/2019 by RWSN Secretariat

Photo – Diani Beach, Kenya. Dan Rata/Shutterstock, via The Conversation

Nuria Ferrer Ramos, Universitat Politècnica de Catalunya – BarcelonaTech

Industry is growing along Kenya’s coast, and some of these companies – such as mining and agricultural companies – are water intensive. To meet their demand, most industries are turning to groundwater.

Groundwater is a natural resource that exists beneath the earth’s surface in soil pore spaces and in the fractures of rock formations. It can be stored in, or move through, aquifers: a body of permeable rock – like gravel or sand.

Groundwater has many intrinsic advantages: it can be developed quickly (and at a relatively low cost), it’s easy to find, it’s drought resilient and can meet water needs on demand. This has made it a crucial component in rural water supply, and for industry.

The problem is, even though Kenya has policies, laws, and institutions that are specifically dedicated to managing groundwater, in practice, groundwater is treated as a common pool resource, belonging to whoever owns the land overlying the aquifer. The majority of water users ignore the potential long-term consequences of unregulated use.

This is what’s happening in Kwale county, on the southern coast of Kenya. Over half a billion US dollars in capital investment has been made in two water-reliant industries in Kwale: heavy sands mining and commercial sugarcane. In addition to this Kwale also hosts significant tourism.

Because aquifers in Kenya are not always properly managed, my colleagues and I wanted to know how increased abstraction of groundwater by industries could affect local communities that use groundwater as their main water supply.

We found that, at the moment, the new industries are not affecting the water supply for local communities. What is affecting the community wells are long drought periods, such as the last drought which lasted from 2016 to early 2017. The consequences of dry wells are that people have to walk further to get water, and water becomes more expensive to buy.

For industry, understanding investor risk and liability for groundwater sustainability would seem prudent, if not a legal obligation, before major abstraction starts.

Our research shows that groundwater resources can be significant and resilient to unpredictable but recurrent drought events, if understood and managed properly.

Sustainable use?

We focused our study on the Msambweni aquifer, located on the coast of Kwale county in Kenya. This aquifer system is composed of a shallow aquifer (about 25 metres thick) and a deep aquifer below this shallow aquifer (about 350 metres thick).

The shallow aquifer is recharged by rain through the ground surface and the deep aquifer is recharged by water that flows underground from the Shimba Hills.

The shallow aquifer is mainly exploited by the local rural communities and the hotels located near the coastline. The deep aquifer is exploited by the mining and sugar operations.

The communities rely heavily on shallow groundwater, which they get from wells or by using a handpump in a borehole, because they don’t have piped water, and water from the two main rivers in the area is not considered safe to drink. Also, in the 1980s, the Swedish International Development Agency installed hundreds of handpumps at boreholes in Kwale county.

Industries now also rely on groundwater. But they use new boreholes, equipped with electrical pumps, that reach the deep aquifer. These have higher abstraction rates than traditional dug wells or shallow boreholes equipped with handpumps.

When investigating whether these users are using the groundwater sustainably, it’s important to point out that sustainability is variable through time. Not all water users exploit the same aquifer layers.

At present, the main industries in the area exploit the deep aquifer because it’s more resilient to drought. So the industries aren’t affecting the shallow community wells.

However, this could change. If droughts become more frequent, or last longer, there will be less groundwater stored.

Data challenges

It’s important to highlight the data challenges we faced, and how we reached our findings.

We tried to define the groundwater abstraction of all the main users, but couldn’t. As in many other countries, abstraction data for wells and boreholes is difficult to get.

So we needed to come up with a new methodology to estimate how much abstraction was happening in areas with uncertain or no data.

Collaboration between stakeholders during this study was essential.

Most of the time, water-reliant users such as the industries collect specific hydrogeological information, like aquifer storage or how much they pump, because they’re trying to use the water efficiently.

We also identified hotels, noted the number of their rooms and interviewed hotel managers to estimate tourism abstraction along the coast using easy tools like Google Earth and TripAdvisor.

Alongside this, it was important to develop a monitoring network, covering the whole aquifer area. We used well measurements to get an idea of the aquifer system, its volume and dynamics, and assess the sustainability of abstraction.

Future approaches

While this data pointed to a scenario where industry was having a minimal impact, things could change.

Enterprises and government may find environmental sustainability of secondary importance to advancing economic production, creating local jobs and new sources of taxation. Government leadership is needed to manage the aquifer as a system for all, including environmental services, rather than for the powerful few.

Albert Folch, Mike Lane, Daniel Olago, Jacob Katuva, Patrick Thomson, Sonia Jou, Rob Hope and Emilio Custodio were key contributors to this study

Nuria Ferrer Ramos, Hydrogeologist, Universitat Politècnica de Catalunya – BarcelonaTech

This article is republished from The Conversation under a Creative Commons license. Read the original article.

This study was funded from the UK Government via NERC, ESRC and DFID as part of the Gro for GooD project (UPGro Consortium Grant: NE/M008894/1). Nuria Ferrer is affiliated with the Department of Civil and Environmental Engineering (DECA), Universitat Politècnica de Catalunya (UPC), Jordi Girona 1-3, 08034 Barcelona, Spain. Associated Unit: Hydrogeology Group (UPC-CSIC), Spain.

Importance of groundwater stressed at climate conference

Posted on 15/10/201914/10/2019 by RWSN Secretariat

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

Posted on 14/10/2019 by RWSN Secretariat

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

Hidden Crisis project presentation in the China Africa water Forum Series No. 7, at Windhoek, Namibia

Posted on 06/09/201904/09/2019 by RWSN Secretariat

By Dessie Nedaw
8 August 2019

The China Africa Water Forum is a platform for all professionals within the fields of water science and technology in Africa and China. The China Africa Water Association also referred to as CAWA, is a non-profit organization that predominantly organizes annual events. One such event was held for three days from July 22 to July 24, 2019 in Windhoek, Namibia with title “Risk Reduction through Sustainable Water Management in Developing Countries”.

The conference was the seventh of the series held under the title China Africa Water forum. The conference has been prepared in collaboration between China Africa Water Association and Namibia’s chapter of Association of Hydro-geologists and other stakeholders.

The opening speech by Minister of public enterprise has emphasized the current fresh water supply challenge of Namibia facing and the possible solution of desalinization as the future option. The Chinese Ambassador in Namibia has emphasized on the neeed of China Africa partnership in a win-win strategy based on mutual benefits. He mentioned the similarities of challenges faced by both China and Africa and stressed some of the innovative approaches and technologies in China stressing the importance of the forum for transfer of skill and knowledge. Nearly 25 presentation from Africa and China covering a wide range of water related topics focusing in reducing risk of water supply, management and sustainable utilization water resources, transport and diffusion of water pollutants and exploration and development of groundwater has been addressed during the three days conference.

The Hidden Crisis project work was presented at the conference within the groundwater exploration and development theme – highlighting the work of the project to apply a tiered approach to assess functionality of handpumped borehole supplies in terms of different levels of performance. The findings have shown this approach to be helpful to unpack national statistics and develop more nuanced understanding of functionality within the country.

The experience has given opportunity to highlight the project and also given good opportunity to share ideas from other professionals, particularly Chinese water experts. Ethiopia has formally requested to be the next organizer of China Africa water forum in the meeting.

Figure: Dessie Nedaw

Technical brief now available – Project approach for defining and assessing rural water supply functionality and levels of performance

Posted on 05/09/201904/09/2019 by RWSN Secretariat

The Hidden Crisis project team have now published a Technical Brief on the methods developed and used by the project to assess rural water supply functionality and levels of performance – now available from here.

This technical brief is aimed at sharing the learning and approaches developed by the project to look at how the functionality and performance levels of boreholes equipped with handpumps (HPBs), can be assessed using a common set of definitions and methods. A tiered approach to defining and measuring functionality was found to be useful to examining functionality for different scales and purposes of monitoring.

The report is aimed at national and regional actors involved in the provision and monitoring of rural water supply functionality.

The brief sets out the tiered functionality definitions, and accompanying survey methods, which were developed by the project and have been applied in functionality surveys across Ethiopia, Uganda and Malawi .

Photos: BGS © UKRI. Survey 1 Field teams, Uganda and Malawi

Study shows boreholes are key to drought resilience in Ethiopia

Posted on 28/08/201927/08/2019 by RWSN Secretariat

BGS Press Release

Installing more boreholes to tap underground water will improve rural Ethiopian
communities’ resilience to drought, according to a new report.

Research carried out by the British Geological Survey (BGS), the University of Addis Ababa and the Overseas Development Institute (ODI) showed that people who have access to groundwater from boreholes are much less affected by drought than those who rely on wells or springs for their water supply. The report also links the shortage of water to:

conflict in local areas
migration
a decline in breastfeeding rates
a rise in miscarriage rates
more children missing school

Groundwater experts from the BGS monitored 19 hand-dug wells, springs and boreholes in two districts in northern Ethiopia over 18 months. They also held focus-group discussions with local people, including school and health centre staff, near each of the groundwater sources.

The team found that boreholes drilled to 50–100 m were the most reliable source of water during the extended drought of 2015–16 and through the dry season.

Prof Alan MacDonald, the BGS hydrogeologist who led the research, said: ‘We found that
boreholes equipped with hand pumps were more reliable than springs or hand-dug wells, and this reliability was not affected by drought or seasonal change. As hand-dug wells dried up and springs failed, the boreholes we monitored gave exactly the same flow throughout the year.

‘Boreholes also had better water quality. As the drought ended and rain started falling many of the springs and hand-dug wells became grossly contaminated. The boreholes performed much better, with less than half of them showing any level of contamination.

‘Our findings make a clear case for the installation of more boreholes to improve resilience to drought. If constructed carefully and regularly maintained, boreholes can transform the water security for rural villages and make them much more resilient to the effects of climate change.’

Dr Seifu Kebede, from Addis Ababa University’s earth sciences department, said:

‘A significant finding of our study is the length of time people without boreholes spent in water collection during the dry season and drought, and the very low volumes of water they were able to collect.

‘People were routinely queuing for up to 10 hours, which led to tension and sometimes violence, and had wide-ranging impact across communities. Women breastfed less and experienced more miscarriages, meals were missed and farm work was reduced to help collect water. School attendance was down in all but one district, as children were involved in water collection. All health centres in the study area reported increases in diseases, and, in some cases, employees were paying for water collection to keep the centres functioning.

‘We must look at how communities source water during a normal dry season to predict how they will cope during drought years. This study shows that boreholes, where they can be installed, could be the most reliable source of groundwater in these areas of northern Ethiopia.’

According to the BGS’s African Groundwater Atlas, Ethiopia has a high potential for groundwater in the highland regions due to the mostly permeable rocks. A major challenge, however, is the rugged terrain, which can hinder the movement of drilling rigs.

The project was funded by the Natural Environment Research Council (NERC) and the Department for International Development (DfID).

The full paper is available in Environmental Research Letters.

For further details please contact:
Sarah McDaid (sarah@mcdaidpr.co.uk/07866789688)
Twitter: @BritGeoSurvey

Editors note:

This week, groundwater experts from around the world will be attending a meeting of GRIPP at the SIWI World Water Week to discuss how to governments and aid agencies can take evidence like this into account when designing and implementing their policies and projects, and specifically around an exciting new groundwater initiative with the African Minister’s Council on Water (AMCOW)

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

Posted on 21/08/2019 by RWSN Secretariat

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

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

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

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

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

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

Tanzania: Not yet evident in this basin

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

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

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.

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

Posted on 14/08/2019 by RWSN Secretariat

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

A 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 London, Cardiff University, University 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.