1 00:00:05,040 --> 00:00:11,140 (Transcribed by TurboScribe.ai. Go Unlimited to remove this message.) Welcome to Mind the Globe, the podcast where we dive into some of today's most pressing global challenges. 2 00:00:11,920 --> 00:00:17,160 We are a team of seven international students from the Junior Research Lab at Institut Agro Montpellier. 3 00:00:17,580 --> 00:00:21,180 Here to explore the issues that shape our world and our future. 4 00:00:30,060 --> 00:00:33,380 Hello professor Niko Verhoest and welcome to the Mind the Globe podcast. 5 00:00:34,200 --> 00:00:36,200 Today we will be diving into the topic of floods. 6 00:00:36,200 --> 00:00:39,700 But before we begin, let's take a moment to introduce you. 7 00:00:40,500 --> 00:00:42,640 I know you as a professor at Ghent University. 8 00:00:43,120 --> 00:00:48,020 But for our listeners, could you briefly share a bit about yourself and your background as a scientist. 9 00:00:48,340 --> 00:00:52,100 Yes, so I'm Niko Verhoest, I'm a professor at Ghent University. 10 00:00:52,500 --> 00:00:58,000 I'm mainly teaching courses on hydrology and water management and flood mechanics. 11 00:00:59,000 --> 00:01:08,300 As a scientist, I'm mainly involved into hydrology, remote sensing of hydraulical variables and stochastic hydrology. 12 00:01:09,220 --> 00:01:22,040 So that's mainly where my background is in, let's say, remote sensing applications, soil moisture, also something on flooding in hydrology. 13 00:01:22,520 --> 00:01:25,340 And how to apply these into hydrological models. 14 00:01:25,960 --> 00:01:37,400 Okay, since much of your work focuses on hydrology and flooding, I'd love to know what inspired you to dive deeper into the topic of floods and make it such a significant part of your research. 15 00:01:37,680 --> 00:01:39,900 My main concern is water management. 16 00:01:40,420 --> 00:01:47,460 So we are looking as engineers to all types of problems that water can have on people. 17 00:01:47,460 --> 00:01:49,540 One of the problems is flooding. 18 00:01:50,020 --> 00:01:55,880 So we want to know where floods could happen, when they would happen, and so on. 19 00:01:56,000 --> 00:02:01,540 So I got into this topic through remote sensing. 20 00:02:01,740 --> 00:02:05,840 So what we want to do is use remote sensing for updating hydrological models. 21 00:02:07,020 --> 00:02:13,600 Hydrological models, they provide you input to hydraulic models and hydraulic models can be used for floods mapping. 22 00:02:13,600 --> 00:02:17,380 So the way I got into touch with flooding was through the hydrological modelling. 23 00:02:17,600 --> 00:02:24,220 So we try to improve extreme discharges and then these can be used into hydraulic models. 24 00:02:25,120 --> 00:02:29,000 Okay, so Professor Verhoest talked about hydrological and hydraulic models. 25 00:02:29,580 --> 00:02:31,420 Let's discuss the difference between the two. 26 00:02:32,520 --> 00:02:36,880 Hydrological models focus on the process of converting rainfall into runoff. 27 00:02:36,880 --> 00:02:45,180 It estimates how much water will flow into rivers based on factors like precipitation, sunshine, and evaporation. 28 00:02:46,460 --> 00:02:52,980 In contrast, hydraulic models deal with the movement and behaviour of water once it is in the river system. 29 00:02:53,740 --> 00:03:02,300 They predict water levels, flow velocities, and potential flood risks by modelling how water is routed through rivers and other channels. 30 00:03:03,000 --> 00:03:12,920 Simply put, hydrological models are about water quantity entering the river stream, while hydraulic models analyse how the water moves within the river. 31 00:03:13,900 --> 00:03:17,020 Okay, now we know something more about your work and background. 32 00:03:17,380 --> 00:03:21,740 But I'm curious, what project or collaboration are you most proud of in your career? 33 00:03:21,740 --> 00:03:32,440 I think we are very proud at Ghent University, at our lab, on the work we did on remote sensing. 34 00:03:32,780 --> 00:03:37,900 So we have done quite a lot of work on soil moisture estimation from radar. 35 00:03:40,280 --> 00:03:43,320 And for that we did quite a lot of work for ESA. 36 00:03:43,320 --> 00:03:47,220 And also for, for instance, the SMOS satellite. 37 00:03:47,580 --> 00:04:01,720 We have been selected as the principal investigator for a project to demonstrate the benefit of SMOS observations for hydrological monitoring. 38 00:04:02,620 --> 00:04:20,339 And so we were able as a small research lab in Ghent, we were heading a project together with Princeton University, together with Toulouse, who are the developers of the SMOS, together with Melbourne University. 39 00:04:21,060 --> 00:04:30,300 And so we had quite a lot of high stake researchers along with us, but we were able to manage this project. 40 00:04:31,560 --> 00:04:36,560 And so this, I think we did some interesting work and so quite some of the research has been published there as well. 41 00:04:37,320 --> 00:04:48,280 So I think that was one of our, because of a long term research on radar remote sensing, that we were able to guide such a project, to supervise such a project. 42 00:04:49,100 --> 00:04:52,320 All right, as you've heard, Niko Verhoest talks about SMOS. 43 00:04:52,820 --> 00:04:54,960 But what exactly are SMOS observations? 44 00:04:55,440 --> 00:04:56,140 Let's take a look. 45 00:04:57,260 --> 00:05:03,320 SMOS observations are collected by a satellite that measures the natural emission of microwaves from the earth. 46 00:05:03,320 --> 00:05:09,200 These microwave signals vary based on the earth's surface temperature and soil moisture content. 47 00:05:10,360 --> 00:05:17,620 By analysing the emitted microwaves, SMOS data allows researchers to estimate soil moisture levels across large areas. 48 00:05:18,500 --> 00:05:26,440 This information is then integrated into hydrological models, where the observed soil moisture is compared to model predictions. 49 00:05:26,440 --> 00:05:40,640 Through data assimilation, these observations are used to update and refine hydrological model outputs, leading to more accurate estimates of soil moisture and improved predictions of river discharge. 50 00:05:41,420 --> 00:05:49,240 This kind of developments are particularly crucial as climate change continues to transform weather patterns across the globe. 51 00:05:49,240 --> 00:05:58,460 Shifts in rainfall distribution, increasing extremes in water events and disturbances to natural water systems are becoming more frequent. 52 00:05:59,500 --> 00:06:05,740 Such changes raise pressing questions about how we can prepare for and respond to these challenges. 53 00:06:06,880 --> 00:06:15,660 With that in mind, my next question is, how do climate change and global warming influence both the frequency and intensity of floods? 54 00:06:16,760 --> 00:06:20,900 We expect that the frequency and intensity will be increasing. 55 00:06:21,840 --> 00:06:26,660 The reason is that due to climate change, we will get warmer air. 56 00:06:27,900 --> 00:06:32,660 If you have warmer air, then we know that more water can be held by the atmosphere. 57 00:06:33,440 --> 00:06:38,140 So if you have more water in the atmosphere, we can also face bigger rainstorms. 58 00:06:38,140 --> 00:06:55,040 So if you have rain with a much higher intensity falling on the land, then this will cause much more water that is flowing to the rivers, and rivers have to try to transport all this water to the sea. 59 00:06:56,060 --> 00:07:02,620 But the rivers are not large enough, so that means that they will overtop and they will cause flooding. 60 00:07:02,620 --> 00:07:09,860 Given the fact that we expect more of these big rainfall events, we can also expect more flood events. 61 00:07:10,900 --> 00:07:14,280 In the face of these growing threats, proactive measures are essential. 62 00:07:15,540 --> 00:07:18,880 This is where flood forecasting and early warning systems come into play. 63 00:07:20,340 --> 00:07:27,460 These systems are vital for saving lives and minimising damage by prediction when and where floods might occur. 64 00:07:27,460 --> 00:07:38,800 By providing timely information, they enable communities to prepare and respond effectively, mitigating the devastating effects on people, infrastructure and ecosystems. 65 00:07:40,160 --> 00:07:48,040 Given their importance, could you explain the science behind flood forecasting and how early warning systems work to keep us safe? 66 00:07:48,910 --> 00:07:56,120 So if you look at flood forecasting, that mainly concerns physical modelling. 67 00:07:56,500 --> 00:08:03,500 So we try to solve the partial differential equation that is valid for a river. 68 00:08:06,260 --> 00:08:12,780 That's quite challenging, so it means numerical modelling that we have to do to solve this. 69 00:08:12,780 --> 00:08:20,580 So we need to do that with good information about how the river is looking like, what the shape of the river is at different sites. 70 00:08:21,500 --> 00:08:28,100 And by that we can try to model or to solve the partial differential equations. 71 00:08:28,720 --> 00:08:30,500 So that's the science behind it. 72 00:08:30,820 --> 00:08:40,020 Let's say that the physics is already known for a very long time, but the way to solve it takes quite some time. 73 00:08:40,020 --> 00:08:47,140 Although with current computers, the time to solve these equations is much shorter. 74 00:08:48,020 --> 00:08:52,480 So that is the current status. 75 00:08:53,140 --> 00:09:00,900 So these models are well developed and we keep on making them a little bit more complicated by going from 1D to a 2D or maybe 3D model. 76 00:09:02,020 --> 00:09:06,300 But they are all based on physics that is quite well known. 77 00:09:07,000 --> 00:09:08,420 But there are some challenges with them. 78 00:09:08,420 --> 00:09:16,340 One of the challenges is to estimate the roughness coefficient for each section in the river, which is not known. 79 00:09:17,620 --> 00:09:20,880 So often this is a calibration parameter. 80 00:09:22,060 --> 00:09:27,100 But this roughness can change in time, because for instance vegetation may grow, so the roughness may grow. 81 00:09:27,240 --> 00:09:29,480 So that's also a question of how do you deal with that. 82 00:09:30,300 --> 00:09:31,920 So that's a tricky one. 83 00:09:31,920 --> 00:09:40,920 So we can do it partially by including some observations and use these to try to estimate the roughness. 84 00:09:42,240 --> 00:09:48,960 But then these models, they're pretty good and they can be used in forecasting. 85 00:09:49,120 --> 00:09:55,860 That means that you also would need a forecast of the discharge that is going into the river. 86 00:09:55,860 --> 00:10:03,380 So for that you need hydrological models that convert the rainfall into inflow to the river system. 87 00:10:04,620 --> 00:10:12,460 Of course, the better the hydrological models, the better the input to the river system and the better the hydraulic predictions will be. 88 00:10:12,980 --> 00:10:18,300 But as you know, this will also be uncertain, this hydrological model. 89 00:10:18,520 --> 00:10:21,140 So uncertain input goes into your hydraulic model. 90 00:10:21,140 --> 00:10:24,740 Your hydraulic model makes errors itself also. 91 00:10:25,160 --> 00:10:33,420 So that means that the predictions are quite certain for the very first few hours in head time. 92 00:10:33,660 --> 00:10:39,820 But the further you go into the future, the more uncertainty of the predictions will become. 93 00:10:40,560 --> 00:10:50,180 Now, if you can forecast with a certain certainty for a couple of hours to days, then you can use it to warn people. 94 00:10:51,140 --> 00:10:53,620 That a flood may happen and so on. 95 00:10:54,100 --> 00:10:59,140 Of course, this will be, let's say, the floods that overtook the riverbanks. 96 00:11:00,400 --> 00:11:06,940 But if the riverbanks would fail at certain points, this is something that cannot be estimated by the normal models. 97 00:11:07,040 --> 00:11:10,480 Because then you should know where the banks will fail. 98 00:11:11,340 --> 00:11:16,060 So not all of the floods can be predicted that easy. 99 00:11:16,060 --> 00:11:26,800 But if you have some predictions of a couple of days in advance, then you can start warning people so that they can try to get rid of the most expensive things in the flooded area. 100 00:11:27,100 --> 00:11:33,360 So that they can try to decrease the costs that will be along with a flood event. 101 00:11:34,400 --> 00:11:38,360 Recent events in the south of France highlight the importance of such systems. 102 00:11:38,360 --> 00:11:49,940 On October 17, 2024, the region was struck by extreme rainfall, with some areas around the Ardèche recording up to 600 mm within 48 hours. 103 00:11:50,920 --> 00:11:55,840 This catastrophic rainfall event resulted in massive flooding and significant material damage. 104 00:11:56,740 --> 00:11:58,400 Could an event like this have been predicted? 105 00:11:59,160 --> 00:12:05,280 And are there measures that could have helped prevent or mitigate the devastating impact of this rainfall in the Ardèche? 106 00:12:05,280 --> 00:12:06,700 Difficult question. 107 00:12:07,020 --> 00:12:08,660 In that sense, could we predict? 108 00:12:09,040 --> 00:12:10,180 Yes, most probably. 109 00:12:10,340 --> 00:12:16,620 I think that Meteo France somehow predicted also that the rain was going to be very, very high. 110 00:12:17,160 --> 00:12:21,280 You could put this into a hydraulic model and you would see that floods would happen. 111 00:12:22,500 --> 00:12:24,280 And so you could use that in warnings. 112 00:12:25,520 --> 00:12:30,880 But preventing it would need some management to your river system. 113 00:12:30,880 --> 00:12:37,120 And this management means that you may need some flood basins or things like that. 114 00:12:37,580 --> 00:12:39,860 It's something that you cannot install in a couple of days. 115 00:12:40,400 --> 00:12:43,480 So we need to manage the river system. 116 00:12:43,800 --> 00:12:50,700 And this is something, sometimes projects of many years, where you have to investigate where are you going to do some mitigation measures? 117 00:12:51,000 --> 00:12:52,240 How are you going to do them? 118 00:12:52,320 --> 00:12:54,400 To what extent will they work? 119 00:12:54,520 --> 00:12:54,940 And so on. 120 00:12:55,020 --> 00:12:57,420 So that's something that cannot be done in a couple of days. 121 00:12:58,960 --> 00:13:04,540 So preventing, yes, but to a certain extent, we cannot prevent everything. 122 00:13:05,040 --> 00:13:07,260 So I think that this is what happens now. 123 00:13:08,220 --> 00:13:22,660 Warning and trying to get ready to save people and to enroll some disaster plans or to make them work is the only thing that you can do at that point. 124 00:13:22,660 --> 00:13:31,060 But really taking measures that will mitigate the full extent of the flood is, I think at that point, impossible. 125 00:13:31,960 --> 00:13:43,600 While traditional approaches to flood prediction and mitigation rely heavily on long-term planning and physical infrastructure, they often fall short in addressing the full extent of extreme events like those seen in the Ardèche. 126 00:13:44,300 --> 00:13:47,060 This is where state-of-the-art technologies come into play. 127 00:13:48,160 --> 00:13:51,580 Artificial intelligence is a hot topic in nearly every field today. 128 00:13:52,440 --> 00:13:54,600 Revolutionising the way we solve problems. 129 00:13:55,740 --> 00:14:00,660 Its potential in managing natural disasters like floods is particularly exciting. 130 00:14:02,380 --> 00:14:08,180 How do advanced technologies like AI, machine learning and satellite imaging improve flood prediction? 131 00:14:09,540 --> 00:14:17,840 That's an evolving field where I've been thinking about it quite a long time already. 132 00:14:19,500 --> 00:14:22,240 There's one thing I think is problematic. 133 00:14:23,060 --> 00:14:25,900 If you want to do AI, you need a lot of data. 134 00:14:26,940 --> 00:14:28,800 So you could do AI. 135 00:14:29,660 --> 00:14:38,640 If you would need a lot of data, you would have to go almost global scale or at least include many, many different basins to have sufficient data. 136 00:14:39,080 --> 00:14:40,120 It's a difficult one. 137 00:14:40,340 --> 00:14:45,820 We need data, but the problem here is that it's not only point data, it's also temporal data. 138 00:14:45,820 --> 00:14:57,360 So data at maybe different points within one basin along the river to be sure that you get the extents at the different sides of your river system. 139 00:14:57,760 --> 00:15:09,240 But you also need long, long periods to estimate, to also include the extreme events, because AI will be able to mimic what has happened and extrapolating. 140 00:15:09,380 --> 00:15:10,940 In the end, it's only an empirical model. 141 00:15:11,440 --> 00:15:12,940 Even AI is an empirical model. 142 00:15:12,940 --> 00:15:13,960 I don't know. 143 00:15:14,140 --> 00:15:16,980 We'll see definitely some things being happening. 144 00:15:17,580 --> 00:15:23,240 But at this point, I don't think that AI will provide us a solution. 145 00:15:23,820 --> 00:15:39,100 I believe more in hybrid modelling, which is actually a model that is driven by physics, where there are some components where we still need some empirical work, that there you could use some AI to improve this empirical relationship. 146 00:15:39,100 --> 00:15:50,760 To me, at this point, with my knowledge, I think this has more chance for success than a purely AI-driven flood forecasting model. 147 00:15:51,220 --> 00:16:00,780 While warning systems and long-term river management projects are essential for mitigating the impacts of extreme rainfall events, certain environments present unique challenges. 148 00:16:00,780 --> 00:16:13,560 In urban areas, like regions around the Ardèche, where infrastructures such as roads, buildings and impermeable concrete surfaces dominate, managing floods becomes even more complex. 149 00:16:14,320 --> 00:16:22,620 These densely populated regions face heightened risks of flash floods due to reduced natural drainage and higher runoff levels. 150 00:16:23,620 --> 00:16:27,420 What are the key challenges in addressing flood risks in these urban areas? 151 00:16:27,420 --> 00:16:31,280 How do urban features contribute to these difficulties? 152 00:16:32,040 --> 00:16:35,360 And how can cities better prepare to handle flash floods? 153 00:16:36,200 --> 00:16:38,280 Urban environments are quite difficult. 154 00:16:38,560 --> 00:16:44,760 Urban environments are very often along the rivers, because it's historically that people started to build along the rivers. 155 00:16:45,260 --> 00:16:51,600 And so, one of the problems in urban systems is that the river doesn't have a lot of place. 156 00:16:51,900 --> 00:16:54,840 So, we build near the banks. 157 00:16:54,840 --> 00:16:57,460 So, if the bank overtops, it's in the building. 158 00:16:57,960 --> 00:17:13,800 The main challenge that you have in a city is to make sure that if it floods, it doesn't flood in the city centre or places where there are buildings, but that you try to have the floods happening at places where you don't have buildings. 159 00:17:14,680 --> 00:17:15,839 Now, there are two types of floods. 160 00:17:16,079 --> 00:17:17,280 One is a pluvial flood. 161 00:17:17,400 --> 00:17:22,660 That means that the flood is just mainly coming from water that is flowing overland due to excessive rain. 162 00:17:23,160 --> 00:17:32,700 So, these could be transported, could be routed to some places in the city where you can temporarily trap the water before it goes to the river. 163 00:17:33,080 --> 00:17:33,980 So, that would be one. 164 00:17:34,120 --> 00:17:46,100 So, it could be some kinds like wadis and things like that, that you can take the water to that place and store it until the highest discharges in the river are gone. 165 00:17:46,800 --> 00:17:51,820 Or you can flow it to the river or you can keep it there and let it infiltrate into the soil. 166 00:17:52,660 --> 00:17:56,800 Niko Verhoest explained the management of wadis to overcome pluvial floods. 167 00:17:57,420 --> 00:17:58,160 But what is a wadi? 168 00:17:58,580 --> 00:18:01,700 Well, wadis are a smart water management solution. 169 00:18:02,680 --> 00:18:11,940 They channel rainwater during heavy storms, reducing flood risks and allowing water to infiltrate the soil, replenishing groundwater reserves. 170 00:18:13,120 --> 00:18:26,360 In some areas, they've been adapted to capture and store water for irrigation, making them a practical and sustainable way to manage scarce water resources by improving resilience to droughts and floods. 171 00:18:26,920 --> 00:18:29,220 We just discussed the pluvial floods. 172 00:18:29,680 --> 00:18:31,900 Now we will listen to the second type of flood. 173 00:18:32,740 --> 00:18:45,760 But the other one, which is the fluvial, that means the flood that is coming from the river itself because the river took too much water and just goes into the city and there it doesn't have sufficient place within the banks, so it floods. 174 00:18:45,760 --> 00:18:47,360 That's another one. 175 00:18:47,940 --> 00:19:12,880 For that, I think you need to go to the upstream area of your city and try to create some areas where you can temporarily store excess water in the river so that the water is stored in flood reservoirs so that less discharge flows to the city and thus can be taken, can be transported within the banks and does not overtop. 176 00:19:12,880 --> 00:19:18,880 Of course, this means that you need, for both types of floods, you need different types of systems. 177 00:19:19,840 --> 00:19:22,760 One is upstream of the city. 178 00:19:23,260 --> 00:19:26,060 The other one could be partially in the city itself. 179 00:19:26,960 --> 00:19:35,280 As you've just seen, floods present complex challenges, particularly in urban areas where managing excess water is especially difficult. 180 00:19:35,960 --> 00:19:41,560 However, natural ecosystems like wetlands and forests can play a crucial role in flood control. 181 00:19:42,880 --> 00:19:51,240 What role do you see these ecosystems playing in improving flood resilience and how can we better integrate them into flood management strategies? 182 00:19:52,120 --> 00:20:06,380 These systems, they are typically, well, they're typically areas or they could be areas where especially wetlands or areas which are wet and so near the river from nature. 183 00:20:07,000 --> 00:20:12,080 So these areas could be used to store water when you have a lot of floods. 184 00:20:12,880 --> 00:20:29,880 You could use them for storing water during flood events so that the water is stored within your wetlands and not maybe somewhere downstream in city centers or other places where you could have some costly floods. 185 00:20:30,920 --> 00:20:33,920 So actually, I think these are areas that could be used. 186 00:20:34,680 --> 00:20:41,820 The vegetation is adapted to quite a lot of water so it's not that floods are causing huge ecosystem problems. 187 00:20:42,880 --> 00:20:49,920 Also, with other natural areas like forests and so on, could also store some water. 188 00:20:50,080 --> 00:20:57,100 They can't flood for a while if this is not like weeks and weeks in a row, but they can take some water. 189 00:20:57,520 --> 00:21:10,500 The trees may be in some kind of stress for a while, but they can handle it if the water is then stored there for a couple of days and then is removed when the discharge in the river is safe enough to remove additional water. 190 00:21:10,500 --> 00:21:16,060 So I think that it's an important part that we can use. 191 00:21:16,060 --> 00:21:24,200 We can use some of our natural systems as an additional way of buffering excess water. 192 00:21:24,820 --> 00:21:35,340 Okay, we've talked a lot about floods, their intensity, the challenges they bring, the impacts of climate change and the ways we can manage them through technology and natural solutions. 193 00:21:36,180 --> 00:21:44,200 With all this in mind, what do you think young people should understand about floods and their importance in shaping sustainable water and environmental management? 194 00:21:45,080 --> 00:21:50,840 And do you have any take-home messages, especially for those who might consider becoming scientists in this field themselves? 195 00:21:51,680 --> 00:21:52,620 Yeah, difficult. 196 00:21:53,540 --> 00:22:00,480 But I think it's very important for them to understand that water is a very costly natural resource. 197 00:22:01,300 --> 00:22:07,400 So water, it falls from the sky, but it's somehow not for free. 198 00:22:08,320 --> 00:22:17,560 This water, we can use it for drinking water, but it just needs some modification to be sure that you can use it as drinking water. 199 00:22:18,340 --> 00:22:21,880 But there are two things about the hydrological cycle that is important. 200 00:22:22,100 --> 00:22:24,560 One is too much water, which is in floods. 201 00:22:25,100 --> 00:22:33,300 But on the other hand, I think that's also very important and even more important is that we have to make sure that we also have water when it's dry for very long periods. 202 00:22:33,920 --> 00:22:48,380 And there, I think it should be important that people understand that we need to store the water somewhere in our natural system so that we can use it in, or that the ecosystem can use it in dry periods. 203 00:22:48,960 --> 00:22:52,880 And that means that where we can store it is in the soil, in the ground. 204 00:22:52,960 --> 00:22:53,600 So we have groundwater. 205 00:22:53,840 --> 00:23:05,720 So we fill up the groundwater so that this water can be used during spring, during summer for our plants so that they can grow, that they can, our plants offer coolness. 206 00:23:07,000 --> 00:23:10,220 Somehow plants offer us food, so that's important. 207 00:23:10,680 --> 00:23:14,640 But also in summer, it provides water to the river system. 208 00:23:14,860 --> 00:23:21,520 So if we don't want the rivers to run dry in summer, we actually need the groundwater table to be full in winter. 209 00:23:21,700 --> 00:23:31,160 So we need to be able to infiltrate water into the soil so that we have sufficient water left for the periods where there is not that much water. 210 00:23:31,800 --> 00:23:40,180 And then second, it's typically during hot periods, the periods in summer where people like to go swimming. 211 00:23:40,640 --> 00:23:45,700 And so I think it's not a good idea that each person, each family has its own swimming pool. 212 00:23:46,380 --> 00:23:51,500 Filling the swimming pool during summer when it's a dry period, so we are lacking water. 213 00:23:51,680 --> 00:23:55,220 So then still using that water to fill swimming pools, I don't think it's a good idea. 214 00:23:56,180 --> 00:24:00,360 Taking a shower two times a day or three times a day because it's hot is not a good idea. 215 00:24:00,360 --> 00:24:07,000 So we have to be very careful about the amount of water that we use during dry periods. 216 00:24:07,800 --> 00:24:20,100 And during wet periods, yeah, we have to understand that we will always face floods, but that we can try to reduce them by ensuring that we can infiltrate the water into the soil. 217 00:24:20,400 --> 00:24:25,620 Each drop that is infiltrating in the soil is not flowing to the river and is not causing a flood. 218 00:24:26,220 --> 00:24:43,540 So I think that is important to know and that we need some areas into the landscape that we can use as flood basins so we cannot build everywhere, but you also need to have some spaces that we assign to water. 219 00:24:44,580 --> 00:24:51,740 And that these areas are not used all the time, but maybe only once every 10 years, every 15 years. 220 00:24:52,280 --> 00:24:56,860 You could have multiple uses like agriculture in these areas. 221 00:24:56,860 --> 00:25:01,920 And if it floods, then you can pay the farmer for the cost that he has. 222 00:25:02,860 --> 00:25:07,640 But people have to understand that we need sufficient area for water. 223 00:25:08,480 --> 00:25:09,400 And that's quite important. 224 00:25:09,500 --> 00:25:10,560 So we cannot build everywhere. 225 00:25:11,400 --> 00:25:21,920 And I think that is important for our current generation, but also for the next generation that they are aware that nature will not stop flooding because we build everything. 226 00:25:22,540 --> 00:25:25,500 The more we build, the more floods we will create. 227 00:25:25,940 --> 00:25:26,920 I think that is important. 228 00:25:28,100 --> 00:25:30,900 Thank you, Niko Verhoest, for being with us today on Mind the Globe. 229 00:25:31,260 --> 00:25:32,020 Thank you very much. 230 00:25:32,500 --> 00:25:33,860 And thank you all for tuning in.