Water, a resource with multiple issues and risks!
On March 29, 2023, one week after the first UN water summit since 1977 and on the eve of the announcement of a specific national plan in France by the President of the Republic, Emma Haziza, hydrologist and specialist in the adaptation of our societies to climate change, held a conference at HEC Paris, at the initiative of the student associations ESP'R and HEC Data Minds, to raise awareness of the crucial issues surrounding a fundamental resource of our planet: water. A look back at a conference full of knowledge and practical advice
Auteur/Author of this article: Frédéric Voirin
We drink water every day in France but what do we really know about it?
The hydrologist Emma Haziza tells you more in her conference at HEC Paris, which is accessible on the HEC Paris Youtube channel and its replay is right here (french version only) :
A key expert on a subject that is omnipresent in our lives: water!
Organized by two HEC student associations - ESP'R and HEC Data Minds, dealing respectively with ecology and innovation related to data science - this conference allowed to invite a renowned hydrologist on the HEC campus: Emma Haziza. The students wanted to focus on the use of data in the fight against climate change.
Emma Haziza is one of France's leading experts on water, a doctorate from the Ecole des Mines, a specialist in the resilience of territories to extreme climate risks, and the founder of Mayane Groupe, an applied research center dedicated to climate adaptation. She also runs a startup project within the HEC Paris SSE gas pedal: Mayane Labs. The latter consulting firm uses climate data and data science to assess the exposure of companies to environmental risks, particularly hydrological risks.
During this conference, which was held in a context of increasingly regular droughts, growing pressure on water tables and tensions around the subject of mega-basins (particularly around the Sainte-Soline project in the Deux-Sèvres region), Emma Haziza, who has been teaching for more than 10 years in engineering schools and training mayors and prefects, was able to provide her insight into the water situation in France with pedagogy and kindness.
Many cross-cutting themes were addressed: food, agriculture, geopolitics, economics, risk management, to name but a few. All these themes are now linked by a common denominator: water. A conference which, beyond the urgent observation, also aimed to propose explanations and practical solutions.
From abundance to scarcity?
By dint of being able to obtain water with a simple turn of the tap, we have come to consider this resource as something obvious, almost as a given. However, this obviousness hides a much more complex reality, based on fragile natural balances, which are all the more difficult to maintain as many sectors of our economy are very water-intensive, such as the nuclear industry, the textile industry or the food industry.
Emma Haziza reminded us that in France, it is hard to imagine that a country that has never lacked water, where the spectacular flooding of the Seine in 1910 has left its mark on people's minds to this day, could dry up. And yet, we have already experienced situations of intense drought in the 20th century when we could "cross the Rhine on foot or play bowls along the Rhone River dry".
Droughts, heat waves: the first element affected by these thermal anomalies is the water cycle.
Despite a strong hydraulic production with 21.2 million tons of water produced in France in 2021, the hydrologist rightly reminds us that even recently, we had "warning signals". From December 19, 2022 to January 2, 2023, France experienced a real "thermal anomaly", with the warmest period ever recorded in France!
She reminded the young audience present that there have been 2 particularly critical heat peaks in France: +5.7 degrees in August 2003 (the famous heat wave that caused 45,000 deaths) and another episode almost equivalent to +5.6 degrees compared to seasonal normals, in October 2022 and its prolonged Indian summer. We then speak of winter heat waves. The hydrologist indicates that the first element affected by these thermal anomalies is the water cycle.
In 2005, France experienced a very significant drought. Emma Haziza indicates that "on Belle-Île, 80,000 plastic bottles were delivered. The cost of the water surcharges had cost 2.6 million euros at the time". That summer, the government explained to its citizens that they had to turn off the tap while brushing their teeth to avoid running out of drinking water. Even today, not everyone follows this recommendation. In reality, we consume 5000-7000L of water per day per person in France, notably through our energy consumption which uses nuclear power and we must constantly cool our power plants".
How to preserve our water resources
In France, since 2017, 700 municipalities are in water distress and this has a real cost. This situation is moreover increased in the Hauts-de-France and the Grand Est. But elsewhere in the world, the niña, the counterpart of el niño on water, is a meteorological situation that is settling in permanently. Drought, pollution and loss of biodiversity: "Global warming invites us to completely rethink our ways of life, consumption and production, including our use of water.
All the more so since
France is warming up faster and more intensely than the rest of the world
Soil drought is very expensive for insurance companies, for example. In France, it cost 2.5 billion euros to insurance companies. Emma Haziza explains that "there is a risk of ending up with a system where insurers would no longer want to cover these additional meteorological costs".
Directly linked to this global warming, there is a risk of eutrophication of rivers (lack of oxygen) for fish. The hydrologist recalls that in 2020, the lake of Enghien reached 29 degrees and saw its fish die because of the lack of oxygen. "70% of the world's rivers could be affected by this phenomenon and even in the high seas, the risk is increasingly present." So it also invites us to rethink the preservation of biodiversity.
The hydrologist reminds us that we have not managed to reach the objectives in terms of water quality in France and "we will not get there by 2025". There are still 380 types of pesticides in our rivers today. I think that giving a river or a water table a legal personality to defend itself is an interesting projection to evolve vis-à-vis the legal power of nature." So our legal models would still need to be reviewed!
Emma Haziza also raises the subject of polluters: "Every year 700 billion euros are given to the agricultural sector without asking for any compensation. But we have to hold the polluters accountable, otherwise we're heading straight for the wall. She specifies:
We have the right to be eco-anxious, but we all have our part to play
We can put microbiota in the soils, we can make it rain in the desert, we are able to act and restore wetlands".
An invitation to question our consumptions patterns
According to Emma Haziza, there is no clear course set for ecology, because "nobody knows where we are going ecologically". She specifies that "in 100 years the soils in France will be exhausted", and advises to "allow them to erode naturally, without pesticides". In China, for example, due to a lack of water, hydroelectric power plants produced less energy and for two days certain regions dependent on these plants had no electricity.
Emma Haziza rightly reminds us, without moralizing, that our direct or indirect consumption patterns remain problematic.
It is time to become aware of what we are contributing to.
Water for our clothes: "The cotton produced for our clothes overconsumes water, overexploiting the water tables on a global scale". The hydrologist reminds us that the worst ecological disaster related to water took place in the Aral Sea: "we lost 70% of its capacity just to produce t-shirts in the 1970s because there were many fashions involving the overproduction of t-shirts. But even today with fast-fashion, Zara for example makes 52 collections of t-shirts per year. 10 years ago, Zara made 2 collections. And these are water basins that don't refill.
Water to feed us: Following a new European legislation, in connection with the EU's GREEN PACT, "we no longer import into France what comes from Amazonian deforestation". However, the hydrologist qualifies his optimism by recalling that "we participate in the deforestation in Ivory Coast by consuming chocolate for example. We also contribute to buy soybeans that will feed our chickens and represents an ecological disaster." The hydrologist wonders about the near future on this subject: "How will we do in 10 years to feed the billions of Chinese and Indians when the water tables or the wells that feed the rice fields will be dry? We increase the amount of water on the surface and therefore its evaporation, so the water runs off but no longer infiltrates the soil and gradually disappears."
What are the solutions to reduce our water consumption on a large scale?
We need to recreate coherence. And if we don't do it, the Earth will force us to do it.
Emma Haziza has analyzed several possible solutions.
For access to fresh water: "There is 97% of salt water to be desalinated hypothetically. If you have the means and oil to ensure the infrastructure and transportation that this requires, you can desalinate sea water" (as in the Atacama Desert, the most arid in the world). Faced with this uncertainty about the depletion of the oil source, Emma Haziza throws in with a touch of irony "maybe we'll go to solutions more based on solar energy."
For our agriculture: "We can't afford to extract from the water table like with the mega-basins: the water must stay in the ground. We must transform the agricultural model to rethink our production methods in a more sustainable way. There are simple solutions, such as hedges. A tree is a natural air-conditioner, but we still need to be able to water them. We can raise animals that consume less water. We can avoid intensive breeding. "
For our energy: "Nuclear is an even more sensitive issue than agriculture. I still think it's a colossus with feet of clay because it still relies on our waterways."
For our state policy: "I felt a new political inflection: the Department of Ecology talking about +4 degrees, a water plan, an unprecedented summer to experience. I don't know if this will translate into political facts but there is a concrete awareness and it comes from all classes of population. And I hope we'll be able to act before the boomerang returns."
How can we act at the individual level?
Emma Haziza is not in favor of coercion because "it's not pleasant, I think we need to guide people, to make them understand that they are vulnerable and also to accompany them psychologically to these changes in behavior. I'm still looking for solutions on how to do that best, in a straightforward way. "
Despite these initial reservations, the hydrologist gives us some very concrete recommendations and advice.
We can show food resilience by eating products that are closer to us and less processed
Emma Haziza points out that by adapting our diet, we win on the water and carbon issue! "We need to reduce our share of meat and we won't have much choice. 90% of OECD countries produce cereals for livestock. We will have to reduce the share of meat to keep these cereals for humans. Today there are 2% wild animals and 85% livestock. The remaining 13% are mankind and our domestic animals. The imbalance is no longer tenable, the IPCC is clear on this issue. I personally stopped eating meat and I live it very well.
Everyone can think about it and act now, on a daily basis and quite simply with basic eco-actions
Turning off the lights and heating in rooms where you don't live, reducing your heat or food consumption, installing aerators on your taps to reduce waste, reusing rainwater for watering, reducing the volume of toilet flushes, buying only really useful and eco-designed clothes. All these small gestures also serve to mitigate our overconsumption of water.
Data science in the fight against climate change: where to act in real time
To make the right decisions, we need "eyes to observe reality", says Emma Haziza. "We need to monitor our territories to know where to act. I have the impression that we are undergoing crises and that we don't have the necessary foresight to react".
Neuromarketing has been used a lot, but data-science has been used very little to regulate our water consumption
These data would allow us to know in real time what is happening under our feet, in our fields and globally with regard to our consumption patterns.
And this is where Emma Haziza sees the tremendous potential of data: according to her, "tomorrow, everyone must be able to be a kind of climate advisor: to be able to tell if their water table is suffering, if we can produce according to real local needs, if we can build new buildings with sense to live sustainably. It is really up to us to ask ourselves if this economic model is really necessary.
As a conclusion, we can't deny that water is present everywhere in our lives, on our plates, in our clothes, in our electricity, in all our activities. Thus, ESP'R and HEC Data Minds students have proposed to examine, with the hydrologist Emma Haziza, the systemic issues that will arise around this resource in the coming decades. From the overexploitation of groundwater to the disruption of the water cycle and conflicts of use, all topics were discussed with pedagogy and without taboos. The students and the hydrologist reminded us of the possibilities offered to us in our daily lives and by data science and AI to better predict and control this risk.