[00:00:00] Bridget Scanlon: Welcome to the Water Resources Podcast. I am Bridget Scanlon. In this podcast, we discuss water challenges with leading experts, including topics on extreme climate events, over exploitation, and potential solutions towards more sustainable management. I would like to welcome Seifu Kebede, who has been a professor of hydrology at the University of KwaZulu Natal in South Africa since 2019.
Seifu grew up in Ethiopia and received his bachelor's and master's in Addis Ababa and his PhD in France at the University of Avignon. He worked for many years at the Addis Ababa University, focusing on water issues in the Horn of Africa. Thank you so much, Seifu, for joining me today. I really appreciate it.
Thanks Bridget for inviting me.
[00:00:00] Bridget Scanlon: Right, so SEFU published a book titled Groundwater in Ethiopia by Springer and a pretty comprehensive assessment of water resources in that region, almost 300 pages, a very detailed hydrogeology, water resources, water chemistry data. And Seifu has been involved in projects with many different organizations over the years.
The UK, DFID (Dept. For Intl. Development, UK), International Atomic Energy Agency, World Bank, and many other groups. So Seifu, you recently attended the International Association of Hydrogeologists meeting in Cape Town in September, and you're currently serving as the vice president of the regional chapter for Sub Saharan Africa. And maybe you can tell us a little bit about that meeting and you gave a keynote address at the meeting. So maybe you can tell us some of the things that you learned from that meeting.
[00:01:53] Seifu Kebede: Yes. Thank you, Bridget. yes, the meeting was held recently in Cape Town and there were about 500 participants. So it is the 50th Congress, various groups of professionals, hydrogeologists. And, financing agencies and users, governments and UN agencies were represented there and it was a great meeting.
And as the meeting started, the Congress started with an excursion into various groundwater systems in Cape Town and to see practically, on the ground evidence on the role of groundwater in, in serving humanity, maintaining urban water needs. And, uh, yes, the Congress was largely focused on hydrogeology at various scales from porous scale, measurement of recharge, new approaches of measuring recharge to, global scale, connection between the groundwater systems and adjacent systems like marine systems.
And, so the scale issue has been addressed, groundwater has been dealt with at various scales. And then, there are also because of this new green transition, and revival of the mining industry, I would say, we have seen a few papers on mining and groundwater, both in terms of challenges of dewatering and mining operations to impacts of mining on the environmental systems.
Yeah, it was such a successful Congress. Recently, I gave a keynote address and my keynote address was trying to connect hydrogeology knowledge with use and who is investing and with people and environment, particularly with the context of sub Saharan Africa. So, there is an aspiration in sub-Saharan Africa and Africa in general to enhance its groundwater use from its current very low level.
And overcome, local challenges of socioeconomic challenges, the region is facing and then, I was trying to highlight what is the evidence we have in terms of hydrogeology, in Africa, kind of really achieves this ambitious, source reflected in the World Bank report and other publications, talking quite a lot of positivity around groundwater.
[00:04:19] Bridget Scanlon: Thanks for your time. Well, it sounds like a great congress I wish I could have attended, and I guess it's very fitting that it was in Cape Town when they experienced almost day zero many years ago. So, at that time I think they were almost totally dependent on surface water and since then have been trying to expand groundwater use.
And I think one of the field trips was to Atlantis, which is north of Cape Town where they have managed aquifer recharge program, where they take a waste-water and other water and storage in the aquifers there for that region. It's nice that they are expanding development of groundwater to provide a buffer to surface water, especially during droughts. So that was a nice aspect. And then it's great that you were able to bring all of the different groups together at the Congress, not just the pure hydrogeologists, but also the people involved in financing like the World Bank and then other organizations involved in governance. And trying to advance the role of groundwater in development in Africa. And I really appreciated you shared your PowerPoint with me and your keynote address emphasizing Jude Cobbings work, Waking the Sleeping Giant trying to advance groundwater use for development in Africa. So, as you say, it's very ambitious and difficult to do because we've been trying to do this now for decades, slowly, hopefully making some progress.
Much of your research, Seifu, has been involved in the Horn of Africa, which includes parts of Ethiopia, Kenya, and Somalia. And that region was subjected to about a three year drought linked to La Nina conditions and teleconnections with the Indian Ocean Dipole. But now they're talking about upcoming El Nino conditions and they're concerned about flooding.
Maybe you can describe this problem with trying to manage these extremes going from drought to flood and, and then trying to provide secure water resources and food in that region, considering the context of those extremes.
[00:06:42] Seifu Kebede: Yes, Bridget. This is a very interesting question. The region is impacted or challenged by this extreme weather events learning and, and then, yeah, as a result of these extremes. We see people being displaced in some instances, and then cattle dying and people losing their properties, particularly their cattle, and the livelihood is mostly pastoralism in that region. And yeah, the region has been facing these challenges for a long time. And then with recent climate change, the problem is even more aggravated.
And then that is when we think there is a possibility to overcome these challenges if the right decision and information is available. And one of the areas we are exploring is the groundwater system in the region. Can we use groundwater to sustain lives and also livelihoods. Cattle need water and during emergencies like during droughts, the immediate target is to save life and cattle.
Yeah. So that people do not lose their property and their livelihoods. So groundwater can serve that purpose of responding to emergencies of this sort, and during floods, if the flood is wisely managed, and there is also a natural system through which the flood water is connected to the aquifer and flooding by itself is not a problem.
It's not bad. The flooding becomes bad when we don't know how to manage it. And when people live on floodplains, on flooded areas, nevertheless, flooding could also be an opportunity when you look at it from a groundwater perspective. That is when most of these aquifers are recharged. And then that is why looking under our feet, kind of, there is a silver lining there.
So I'll put it that way.
[00:08:44] Bridget Scanlon: Right. I mean, it's a pretty complex area with complex geology and topography and climate conditions. And so it's not for the faint of heart to try to explore for water resources and manage water resources in that region. So you have described in your book and many papers and everything, different systems.
But in one of your recent book chapters in Global Groundwater Assessment, you showed that there are some areas with low hanging fruit, where it's possible to develop the groundwater more. You mentioned a number of different aquifers, Murti, Bulal, Awash, and many of these regions. And so I think it's great that, there would be first lines that you could look at for water resources and emphasize those regions. And maybe you can describe those aquifers a little bit and some of the challenges with some of the others. I mean, the Rift Valley and some of the water quality issues and some of those others. So describing the hydrogeology of, I know it's a very complex system, but maybe why some of these aquifers, would be good targets.
[00:09:57] Seifu Kebede: Yes. thank you, Bridget. and considering also you listeners could be from other continents and not only from the Horn of Africa region, I would try to make it lighter. yes, it's a complex environment. It's mountainous and the geology is relatively complex compared to other regions. It is challenging in some places to look for good aquifers that have larger storage, transmissivity and connected to a sufficient recharge to sustain withdrawals. And then there are some strategic aquifers I would say in otherwise difficult environment. So I'm talking when I say difficult environment, not the entire Horn of Africa is a difficult hydrogeology environment. These are particular corners of the Horn of Africa region, including Somalia and part of Kenya and part of Ethiopia. Not everywhere. So the rest of the region has some good potential in terms of shallow groundwater, which is for productive uses. So the part that I'm talking about is this challenged region, towards the tip of the Horn of Africa.
And nevertheless, we have these strategic aquifers that can be developed and also protected from both over exploitation and degradation in quality because of the way we manage the land use around these aquifers. One of the threats, for instance, on these aquifers is invasive species, invasive trees, pumping large volume of water into the atmosphere via evapotranspiration pathway. Protection of this strategic aquifers would be the lowest hanging fruit in my opinion. And also, there are hard won, very good boreholes supplying a sufficient volume of water to communities. And then safeguarding this through innovations like monitoring, remote monitoring, there is a U.S. AID financed, innovation by the University of Colorado, I believe, whereby certain devices are fitted onto boreholes, and then the health of the boreholes can be monitored from several hundreds of kilometers away. And then, if something happens to the borehole, maintenance team could be deployed to the site and maintain the borehole, and then safeguarding these boreholes, strategic boreholes. So in terms of emergencies, floods and droughts, then life continues and then livelihood continues.
[00:12:27] Bridget Scanlon: Right. You mentioned that many people in these regions are pastoralists and so cattle are very important to their livelihood. And so maintaining water resources for their cattle and their livestock and stuff is critical.
And, with a lot of emphasis on emergency management, I mean, we go from droughts to floods and everything is an emergency. It's important, I think, to have a longer-term sustainable development goals to manage these systems. So some of these aquifers are complex and you need deep boreholes to get at the water resource, but then there are other shallow systems that are more readily accessed. You mentioned some of the solutions, then how, you know, monitoring the water resources, so people can understand if the boreholes are functioning. And then if they're not, then they can fix them and some organizations like in one of your papers, you mentioned, this group called Fundifix who can be deployed then and go out and try to fix the boreholes and make them operational.
I think that's one of the big issues in Africa is that a lot of the boreholes are not operational and so trying to develop approaches where they can more readily fix them and maintain them and you have published many papers on that issue with some of the people from the British Geological Survey. So I think that's a real challenge, isn't it, to maintain boreholes and maintain them operationally?
[00:13:54] Seifu Kebede: Yes, I think that's a problem all across Sub Saharan Africa, I would say, functional boreholes. Yes, how to put it. But there are innovations. There are new innovations about how to deal with this functionality challenges with the functionality problem arises from many different reasons could be because of engineering will be because of the academic conditions or maybe related to management.
The way the water points are managed by community, by professional providers, et cetera. So recent innovation is growing both around proper, how to properly site boreholes and how to use good materials for the borehole design and also on the management side, managing the water points.
And as you see, University of Oxford innovation on Fundifix is based on private public partnership approach, whereby team of engineers or technicians come and join hands and together and form a local company and finance it by the public, the government, and also the users and philanthropists, et cetera.
And then this group of technicians maintain several boreholes and use the economy of scale to run the system into the future. And then this innovation is tested and is working. Yeah. Can be upscaled in other parts of Africa and with also considering local contexts. Yes, back to you.
[00:15:29] Bridget Scanlon: We talked earlier about how we go from drought to flood and flooding is not necessarily bad because it supports recharging the aquifers.
And your study in the Awash basin really describes some of that. I mean, in many semi-arid regions, surface water recharges the groundwater, and so during flood conditions, then you can get more recharge to the aquifer, and then that can support enhanced development during drought periods. And then there are also solutions like sand dams and other things where you can retain the water in the these ephemeral streams for longer. So that it has a bigger chance to recharge the aquifer. So there are different ways then to try to optimize water management to even out the water supply variability during floods and droughts, you mentioned in one of your papers terracing and to try to reduce erosion and those issues associated with flooding.
So do you see a lot of areas where they deploy sand berms to increase recharge and, and then a lot of siting of boreholes near these ephemeral streams to take advantage of that episodic recharge?
[00:16:47] Seifu Kebede: Yes, Bridget, those strategic aquifers I've mentioned earlier, and most of these are recharging during exceptional rainfall events during floods, and then floods recharge the aquifer, And then it has two advantages. One is in terms of water quantity and also along this flood waters, where the flood water with low salinity. And, yes, and as a region also has some progressive policy measures in terms of, or practices in terms of land management, and there is a number of, programs and projects on sustainable land management, whereby communities come out to the catchment and then, construct soil water conservation structures.
In recent research, again, collaborative research between my university at the KwaZulu Natal University and then the University of Oxford has demonstrated that recharge to groundwater and the storage of groundwater can be enhanced, has been enhanced, and communities which have done these practices have benefited both in terms of use of groundwater for small scale irrigation development and small scale food production and adjacent areas where you don't have those kind of practices are not as well off as communities which have practices, approaches.
Yeah, ephemeral streams recharging aquifers, and then experience also sand dams. I think Kenya is a good example. There are a number of places where sand dams have been constructed. Yeah, communities could do that. And then, yeah, this more or less somehow similar to managed aquifer recharge, but this is more locally contextually applicable method in that region.
There is a scope to enhance this and then to use sand dams as alternatives. Well, there is anyways externalities to any engineering structures that we put in place. There are demonstrations and evidence that sometimes could be good options in some regions.
[00:18:53] Bridget Scanlon: Right. And another thing that you mentioned is the lack of data, and you use the term survival bias in one of your papers. And I've heard this from a number of other people also, is that people don't report when they have dry wells, and they call them test wells or whatever, and you don't know where dry wells have been drilled so that maybe you can avoid those areas or you can learn from that experience or where people have gotten high salinity groundwater or high fluoride water.
And so we would really benefit from more comprehensive reporting that includes these failures, but we don't like to advertise negative things, do we? It would be nice if the reporting would include some of these ideas. Do you have some ideas on that, or it's just difficult to get those data?
[00:19:51] Seifu Kebede: Yes, I think the way data are captured and circulated in certain parts of the world is maybe unique to that part.
In the Horn of Africa recently we made a selfie, the way data are captured and circulated and shared peer to peer, people to people data sharing kind of dominates over centralized data through which, everybody gets access to the data set and then use those data. One way of getting a handle on data that is not reported is to talk to people, people who are involved in drilling.
And then professional organizations like our association (IAH) or local associations, drillers associations, is where you can capture data on these reported borders. Well, it is not always gloomy, but there are ways to capture these data. And that is what I've tried to look into in the Horn of Africa region, talking to people, talking to, and actually looking into the grey literature.
And success rate, evidence on success rate, success rate was kind of captured. But yeah, we also recently did some survey to see if there has been any change. I would say success rate is improving and because of new evidence and new information, use of hydrogeology maps, use of data, use of satellite technology, et cetera, drilling success rate is reportedly improving. Among the community, hydrogeology community in Ethiopia, and that's all of Africa, it is reported that it is increasing in terms of investment or knowledge and data gathering.
[00:21:32] Bridget Scanlon: And so in a lot of cases, it's non governmental organizations, NGOs, and other groups who are involved in drilling boreholes and stuff, and they certainly won't have the level of expertise that you do say on the hydrogeology of the region so they could benefit from an understanding of what's feasible and what's not.
And I think you have been trying to translate your detailed work to something that's more readily accessible to these groups and to other people through maps and other reports. And I really liked those. So we've had, the Germans produced a hydrogeology maps of global hydrogeology maps, and then the British Geological Survey, Alan McDonald and others, developed maps of Africa, the aquifers, and tried to characterize them at a very large scale.
But then the types of maps that you're talking about that you shared with me are like whether it's diggable, whether you could have a dug well or a borehole. And maybe you can describe some of these and then some reports like how far apart you should have your wells if you want to irrigate with a certain amount of water for small holder irrigation projects, and how deep you should have the well to store some water. Maybe you can describe some of these.
[00:22:57] Seifu Kebede: Thank you Bridget. This is another very important question. Very good question. The last decade we have known in Africa many different maps Pan African scale being published by partner organizations. These maps have really led the planning, continental scale planning and I would say policy making.
And nowadays you will see several sub Saharan African countries and African countries adding groundwater into their water security mix, water security mix. And then the city of Cape Town is an evidence for that. The city of Cape Town kind of investing on groundwater, going to draw up to 150,000 meter cube per day and adding that into the city's water the supply system and then aspirations on groundwater that are rising thanks to these maps which have produced evidence at continental scale. Nevertheless, converting these ambitions as well as evidence into real action on the ground among farmers would need huge hydrogeologists, vehicles, drilling rigs. The scale of capacity that is required to realize Africa's ambition on groundwater that is huge. So what path to follow? So one way to go is to go by farmer driven approach. Farmers doing their own survey of the ground data and digging boreholes or digging wells or manual boreholes into into the ground and then monitoring the groundwater data systems and then placing right distance between wells.
This is like hydrogeology made easy or making the Darcy equation more made easy locally. And then what we have been trying to do at local level for the Agricultural Transformation Agency, sorry, Agricultural Transformation Agency in Ethiopia is developing tools and guidelines that are understandable for farmers. And extension agents or development agents to use and then drive sustainable use of groundwater for minor and smaller scale food production. Yes, I think you were asking about the spacing tool, catchment sizing tool, and well depth water column tool. So these tools are to irrigate one hectare of land, what is the water column requirement in a dug well? So this will help the farmer to design is that way made by also supported by the extension agent. So that is a way to overcome the huge capacity need to realize what the government's African states are aspiring and also what financing agencies are kind of trying to support.
[00:25:56] Bridget Scanlon: Right. And I think this follows on, I had an earlier podcast with Paul Bauman, where he works with people in Uganda and other regions, the local people, and helps them figure out where best to site water using surface geophysics and to interpret the geophysics and then to drill the boreholes themselves, hand dug wells, and then to monitor them and maintain them.
And so I think the World Bank has a group called Farmer Led Irrigation Development, FLID, which supports stakeholder involvement. And it seems they are integrally involved in the development of the resource, then they're in a much better position to manage it and maintain it and understand the dynamics. So it won't be voodoo to them. They will be involved with drilling and all of that. And so I think it will help them manage the resource a lot better. So it's a challenge. But I think you mentioned earlier that the recent World Bank report and what they're doing with farmer led irrigation development and emphasizing groundwater development for economic growth and stuff.
I think these are all parts of this issue and trying to achieve some of the aspirational goals that you want for Sub Saharan Africa. One of the things that you mentioned recently in a discussion, Seifu, was these pockmarked depressions at the land surface and that they seem to be associated with an underlying groundwater resource and that some groups are developing these. We don't know that much about them and that we really need to understand them better so that we could protect them and manage them appropriately.
Can you describe these pockmarks seem to be over large areas. Can you describe these a little bit and what you think needs to be done to develop them appropriately?
[00:27:59] Seifu Kebede: I first came across this, pockmark depressions while I was trying to assist the USGS project in that part of the world, and I've made some survey of passive seismic in the depressions.
And yeah, I made a survey of maybe two or three such depressions. And then recently in 2021, a group of German scientists have published a paper on fairy circles in Namibia. These were like tiny, small, circular features. around which the circle is defined by grasses and then looks like very intriguing.
And then, and because of that experience, in the Horn of Africa region, I say, oh, is that part of the world? It has also these circular depressions, but it's different from what you see in Namibia. So the we see in Ethiopia, Somalia, are larger geometric scale and these ones are like a metric scale.
And then I wondered why don't I look across as African scale and realize that they are almost everywhere in dryland environments. And then I was trying to put together a paper, and then we recently presented an abstract at IAH on these pockmarks, and also realized that other groups of people are working on this.
And then I saw a recent publication on pockmarks, they're called fairy circles, and they're exchanged globally, worldwide, in Australia, in Africa. And then. What I was trying to look into is the hydrological significance of these larger pockmarks that we have in the Horn of Africa region, following up on the work I started with the USGS.
And then these depressions are serving like a perched groundwater systems, but are very vital water systems. People can dig wells and then find water in shallow systems in otherwise very deep groundwater areas. There's a regional water table is like 200 meters. And in this pockmarked depressions, in some of these pockmarked depressions, you have very shallow groundwaters and serving cattle, camels, people, what attracts and then these folk market operations are attracting small urban congregations around the depressions and then visually or in the naked eyes are not really visible unless you closely see it is not visible, but the local people know about these features.
They call them bali. In Somali language, it's called Bali. So, yes, we're looking into the hydrological, hydrogeological significance of these features. And yeah, in some places they are being compromised, being damaged because of settlements around these features, contamination and then compaction of the recharge surfaces.
And then that is the kind of things that we need to quickly protect from damage and these are vital water systems that doesn't want to be recognized in the past, but more evidence is needed. We are just at the starting stage to understand these features. We need more research hydrological hydrogeological research on this and yeah, I think if there are finances, funding, interest in funding, then we'll be happy to continue researching these vital water systems and particularly creating also awareness among development partners operating in that region so as to better protect and safeguard the system for sustainable use.
[00:31:32] Bridget Scanlon: Right. I had never heard of them before, but as you say, they're very subtle and so difficult to see on the ground, but you can see them in Google Maps and stuff. You can see these sort of circular features, but then understanding the hydrologic implications of these, how deep is the groundwater, how widespread, and then to manage the resource.
So I think geophysics and you always use geochemistry to understand them. You see quite distinctive geochemistry within and outside them. And then as people become more aware of these, then to try to avoid over exploitation and to manage them appropriately, so that would be great. They could be a real resource in areas where otherwise the groundwater is a couple of hundred meters deep.
And so you would only be able to drill a borehole that deep for maybe a larger scale development or something. So, It's a very interesting area and look forward to learning more about them and trying to see how they can be developed.
[00:32:38] Seifu Kebede: Yeah, let's see if there are any interested parties on this and make further exploration.
Recently, in collaboration with UNICEF, UNDP, we gathered some data on isotopes in waters in this region to look into carbon 14, tritium, several isotopes of water. There is clear evidence that this depression serves as recharge areas containing perched groundwater. And nevertheless, we need to explore this further when we look into the age indicators, tritium and C14.
We felt that some more additional age indicators would be needed, maybe possibly chloride statistics or noble gases or other age indicators may be needed to really understand the groundwater dynamics in that part of the world.
[00:33:33] Bridget Scanlon: Right. And I mean, in the High Plains region of the U. S. where we've done quite a bit of work, we have these circular features called playas.
And early on in the early 1950s and 60s, they thought they were groundwater discharge zones, but then later realized that they were recharge features and then there was some concern because municipal waste and Department of Energy waste was being disposed thinking that they were not recharge features.
So there was some remediation, but so that's the primary place for recharge in the Southern High Plains. Are these playas, so if these features are somewhat similar, maybe they may serve a similar role. You've been in South Africa now for a few years, and do you think that the groundwater situation in South Africa is quite different from that in East Africa, or the Horn of Africa?
Seems like South Africa relies fairly heavily on surface water resources, it may be. There's opportunities for their development of groundwater resources. And maybe then since they have surface water, maybe they could conjunctively manage surface water and groundwater to optimize water resources. What are your thoughts about South Africa, Seifu?
[00:34:50] Seifu Kebede: Yes. I think as you rightly said, South Africa is the country, South Africa is heavily surface water dependent and groundwater accounts for less than 20%. This is just a rough estimation. The exact number may be different, but less than 20 percent of the water supply was for domestic use, industrial use, irrigation, etc.
And because of historical reasons, South Africa is heavily surface water dependent. But The 2015-2016 El Nino has told the hard way is that conjunctive use is an inevitable because of that Day Zero Cape Town has encountered. And then there is no guarantee that other parts of South Africa will not face the Cape Town situation.
And then the government and also was a research commission has rightly identified. To scale research on groundwater recently and in the coming five years, which is a right choice in my opinion. And we need to look into how to add groundwater into the water security mix here in South Africa to overcome the upcoming challenges, climate challenges, and human pressure.
And, the Horn of Africa region, you are right, like in Ethiopia, Kenya, Somalia, maybe with different degree or differences, you see heavy reliance on groundwater, particularly for drinking water supply. And then agriculture is still rain fed largely, but we see pockets of emerging groundwater dependent irrigation, farmers need locally, not really, like, I don't have the right term for that.
Is it, cherry something? Yeah, cherry is a small thing. Yeah, maybe correct my English later. So it's very small scale, but, showing that. This can easily be quickly catch the attention of the other need by farmers and then groundwater can develop very quickly among, can be uptaken by farmers very quickly.
So yeah, there are differences. We see heavy groundwater reliance for drinking water supply in northern Africa region. And in South Africa, it is more surface water reliance, but moving also into adding groundwater into the mix. But there are also differences like we have the SADC GMI, which is a very mature organization that is coordinating the countries on managing the shared aquifers and non shared aquifers as well, I believe.
And in the Horn of Africa region and other regions of Africa, including the Niger and Sahel region, the institutions for collaborative management are yet to be developed and data sharing, particularly data is there, that is my belief, data is somewhere and that data, which is sitting somewhere in a black box, the missing link is bringing this to to light and then using this evidence for decision making.
So in that regard, as a part of Africa is falling behind compared to South Africa.
[00:37:54] Bridget Scanlon: Right, so I think it seems like they're advancing with governance and approaches in Southern Africa. You mentioned SADC, Groundwater Management Institute, GMI, SADC, South Africa, Southern Africa. What does SADC stand for?
South Africa Development Community. Groundwater Management Institute. Yeah. So that's, that's great. And then there is concern, I guess, in some regions of Southern Africa about conserving wetlands and not having groundwater development impact wetlands. And there are some very famous Ramsar sites.
And so is that a concern in many regions or just in localized areas where those wetlands are found?
[00:38:44] Seifu Kebede: Let me see this. I suppose referring to a recent direction on connection between protected environments, conservation areas, and groundwater. I think globally the past experience is that the boundaries of conservation areas and protected environments, wetlands, Ramsar sites, is based on the surface water catchment.
I think that is the way it is, boundaries, protection areas are delineated. It happens so, particularly in dry arid regions, in many tectonically impacted, affected regions, the boundaries of surface water and groundwater do not match all the time. And in this regard, there may be an interest, I think there is a recent publication on that, I don't remember the name right now.
On demonstrating the, if groundwater was factored into delineation of protection area, it could have been different from the experiences or the practices that many countries are doing currently in terms of protecting these vital systems and Ramsar sites, et cetera. So I view this issue in South Africa from this angle.
And in South Africa, we have many protected environments, conservation areas, these wetland systems, Ramsar sites, and evidence is needed on the systems and how they are connected to adjacent groundwater. If we are aspiring to enhancing groundwater use for irrigation development and for other purposes, then we'll need to also safeguard connected systems, connected social systems, connected ecological systems.
So, in that regard, again, part of the research is needed. And, well, we are trying our best to understand the wetland systems in the catchment where my university is located currently. Great. And, yeah, University of KwaZulu Natal Center for Water Resources Research, yeah.
[00:40:52] Bridget Scanlon: Right, right. So, Seifu, you've done a tremendous amount of work in the Horn of Africa now in Southern Africa, and you're serving as the Vice President for the IAH, International Association of Hydrogeologists Chapter.
How do you see groundwater development evolving in the near future? Are you hopeful that we will be able to advance at the small holder farmers, help them secure drinking water supplies and small scale irrigation to support food production and food security?
How do you see it evolving?
[00:41:33] Seifu Kebede: Yes. So Bridget, Africa is a very huge continent. For our readers, Africa has the size of the U. S., China, India, Europe, I think combined. A huge continent. So we have variabilities in hydrology. And then if you look into Africa that is underlain by what we call basement rocks, basement aquifers.
And yeah, by some coincidence, most of these basement aquifers also have high rainfall conditions, rainfall varying between 500 millimeters to up to 1, 500 millimeters. And then these basement aquifers have shallow regolith underlain by intact rocks. And most of the groundwater is recirculating in the shallow level.
Yeah, this may not be appropriate for the kind of irrigation that we see in, in California or in Oklahoma or in other places, but smaller scale farmers with half a hectare, one hectare land, that kind of thing can be, it's feasible and it's possible. Yeah, for instance, if you look into this, what you call the depressions inside, not the depression, not the pockmarks I've talked about, but the depressions between hills in basement aquifer areas, also locally called dambos, they are very extensive.
And also boreholes in basement aquifers. Average yield could be, if rightly sited, according to a recent paper by Bianchi, 2023, I suppose shows borehole yield could be a borehole liter per second could be achieved in this environment. So comparing the area, taking the area, taking the borehole yield, there is a possibility for enhancing groundwater use for food production and drinking water supply.
Well, nevertheless, there are also people who are concerned about this because of wetlands going to be impacted or connected ecosystems may be impacted because of this shallow groundwater development for use. And then every country is unique, every region is unique, and then countries have their own aspirations and then their sequencing of what they want to do in creating awareness about sustainability, but at the same time also creating awareness about possibility of using this for local food production could be, yes, a good option and a viable option in the future, I believe.
[00:44:03] Bridget Scanlon: Right. I think Alan McDonald mentioned that these basement aquifers represent about 40 percent of the land area in sub-Saharan Africa. And so, and the World Bank in their aquifer typology, they use a egg carton to suggest that these are small localized systems that are sort of self-regulating. And so there's not a lot of storage to overexploit. And so maybe these would be ideal then to support smallholder drinking water supplies and small-scale irrigation. And I think the maps that you have been developing, translating your detailed hydrogeology to very simple maps, and then the things you have been developing about boreholes: spacing and depths and all that to support this are very valuable to help translate this to the farmers and hopefully that they can take it on. Our guest today is Seifu Kabedi, who is a professor of hydrology at the University of KwaZulu Natal, and on the website, I will include links to many of his book and his papers and other sources that we mentioned today.
Thank you so much, Sifu, for talking with me today and sharing your knowledge and for all the great work you're doing. I really appreciate it. Thank
[00:45:20] Seifu Kebede: you, Bridget, for inviting, and I was happy talking to you. I, yeah, thank you so much.
