“The reservoirs will no longer be filled as before,” explains Narcís Prat, emeritus professor of Ecology at the University of Barcelona. More desalination, reuse of regenerated waste flows and recycling of water used at home are some of his recipes to face future droughts.
The reservoirs in the Barcelona region are at 16% of their capacity. The emergency is around the corner. How did we get here?
There are two factors. One is the climate, which has changed. We have had three consecutive years of drought with 300 millimeters of rain, as if we were in Almería. We are facing a change in climate and we also do not know if this will last four years or five years; there are many uncertainties. The second part is that at a certain time when a series of investments had to be made, for political reasons, it was decided that they would not be made [period 2009-2017] so that if the 2009 plan had been followed, where it was already Those investments were included, we would already have them. And if we have been able to reach three years without restrictions, with these investments we could have reached four without problems.
At this rate, are we going to be left with empty reservoirs? It’s a dystopian scenario…
The reservoirs will no longer fill as before, due to several factors. The first is the weather. If it rains and snows little and the snow melts earlier, water no longer accumulates in the reservoirs. Before, the thaw began in May and the reservoirs were filled to be able to irrigate in summer; In the future it will not be like that. Irrigation is going to suffer a lot in the future. It was already seen last year, when the Rialb (Segre) reservoir, which is enormous, remained empty, something that seemed possible and happened. There will be no choice but to reduce the number of irrigated hectares in the Ebro basins.
What other factors are there?
Additionally, there are other factors that cause less water to flow into reservoirs. Evapotranspiration of plants, which take water from the soil, depends on temperature. Before, from November to March, the plants practically did not transpire, because it was cold, what rained ran off through the rivers to the reservoirs. But now, since it is hot, they sweat in the middle of winter and, therefore, begin to use water much earlier. This can mean that it can rain 20 liters in an area and almost no water enters the reservoirs. Water reaches the ground, but it only soaks; Trees collect water with their branches and evapotranspire it. The result is that no water comes out of the fountains, no water flows through the rivers, and the reservoirs do not fill. To fill reservoirs, we need much more intense and persistent rain, so that there is enough runoff to go to the reservoirs. And we are not having this and it is not certain that we will have it in the future.
You commented on Lluís Falgàs’ program on TV2 that you had already warned of the risks of these droughts. What was he referring to?
In 2009 we made several reports on water and climate change in which we warned that there would be a decrease in snow resources in Catalonia. It is a job for the Catalan Water Agency where the best professionals from different branches (hydrology to economics) participated. There there was already talk of a loss of river flows of up to 20
You have been very critical of the Generalitat when you point out that the hydraulic works have only been financed with the water fee (which we pay in the water bill that users pay) and that the Administration in all these years has avoided making contributions with the budgets. The cost recovery philosophy has been taken to the extreme, perhaps. No?
In the drought of 2008, the Catalan Water Agency (ACA) asked the Minister of Economy for 300 million euros to undertake emergency works due to the drought from the budget of the Generalitat. The councilor did not have them and told them to go into debt. When the drought ended, the councilor did not remember that he had promised them the money. Successive councilors continued with the trend that hydraulic works in Catalonia were paid for with the fee paid by the user, but as this fee was insufficient and the price of water was not raised, the ACA continued to go into debt. And the debt grew until there was no money for investments, because the ACA was forced to return the debt money to the banks (70 million a year). The fee is a fee, not a tax, and was designed to pay for treatment plants and sanitation, not all hydraulic works. The Generalitat has not allocated any money from its regular budget to the water cycle, nor does it allocate almost anything now. In something as important as this, they have not put the necessary money in these years.
What should fair payment for water be like?
The logical thing would be for the price of water to increase, the variable cost, and for the price increase to be significant for blocks greater than 100 liters/person per day. A consumption of 40 liters per person per day is the vital minimum. People who consume 40 to 100 liters a day already do their homework, because the person is already careful in their consumption and you cannot ask for much more. But more than 100 liters per day of individual consumption, and especially more than 150, should lead to a large increase in the price of the variable cost of water; It would be the only way for large consumers to save. This is so if the objective of water policy is to save water. Now, if the objective is to make money then we may not manage the service well.
We survived the drought thanks to investments planned before the previous drought, thanks to the El Prat desalination plant and the regeneration of Llobregat wastewater
Both the desalination plant and reuse are ideas from the years 2004-2008, and largely the result of the consultation that the then councilor Salvador Milà made to the New Culture of Water Foundation. At that time, a plan was made with the principles of the New Water Culture; that is, efficiency and depending not on a single resource, that of reservoirs, but rather having several resources at the same time: desalination, reuse, a bit of reservoirs and others; It is about having several sources, so that in the future it does not depend only on rain.
Someone may think that we have arrived here as a consequence of the philosophy of the new water culture, understood as a refusal to reject transfers and based on savings, and more focused on desalination and water regeneration. No?
We have arrived here because the government that had this philosophy was succeeded by another that did not have this philosophy. And in fact, a series of actions were taken contrary to this, such as, for example, privatizing the public company Aigües Ter-Llobregat. Public policy was forgotten and we moved on to a period, from 2008 to 2015, in which it seemed that everything had to be privatized based on the assumption that everything private was going very well and everything public was not. It is important to be very clear that large infrastructures (high water) have to be public and obey general planning. Another thing is the management of low water, which depends on each municipality and can be done in various ways (public companies, concession to private or mixed companies).
Neither the region of Barcelona and Girona nor areas of Andalusia seem to be able to hope to solve the lack of water availability in the future by looking at the sky. The liters needed to fill the reservoirs will not fall in the future
Now the Ebro has some water, but next year? You can’t rely on water now to irrigate in July or August. The sky is no longer enough to ensure water for either the countryside or the urban conurbations. We therefore need additional resources, desalination plants and regeneration, which already provide more than 50% of water in the Barcelona area. In Llobregat, 2 m3 of the 4 m3 available are recovered and regenerated. But in Besós, of the 4 m3 that are purified, nothing is regenerated. What has been done in Llobregat can be done in Besós. All this action should also serve to reduce the transfer of the Ter, because the Ter is running out of resources and this transfer must be reduced. Everyone has to do their homework. With desalination and reuse of water we will have a permanent resource, although there will always be a little lack, we cannot completely do without water from the sky.
Is it possible to regenerate the Besòs water?
Regeneration can be done. We have confirmed them in the analyzes of the regenerated water from the El Prat treatment plant that is reused. We have done a study on the regenerated water that is then poured into the upstream river (Molins de Rei) to make it drinkable again at the Sant Joan Despí plant (before distribution). And of the 300 compounds analyzed that could be toxic, only one exceeded the limits; and it is also not very toxic. The study was carried out by renowned experts from universities, research centers and a water company. The quality of the regenerated water from the Llobregat is beyond any doubt. The Health Department has also participated.
Should water regeneration be expanded, then?
In the Besòs area you can do the same as in Llobregat; We should also do the same in the treatment plants on the Costa Brava. The Costa Brava draws water from the Ter and throws it into the sea purified. It is a wasted resource
But until the drought arrived, the device to regenerate the Llobregat water was not used…
This device was not used between 2009 and 2017; and instead of using this device to regenerate water, as well as the desalination plant to reduce the transfer of the Ter, the transfer of the Ter has been maintained, with significant environmental damage.
The engineers propose extending the mini-transfer of Ebro water that reaches Tarragona to the Barcelona region. What do you think?
I believe that this is a poorly thought out solution, it does not even serve as an emergency option.
It would be “surplus” water, which is not used in the concession to bring water to Camp de Tarragona.
There is no excess water in either the Ebro or the Rhône, in the Ebro the current environmental flows are an environmental ruin. Transfers are a topic of the past. Catalonia’s management plan must be followed, taking into account that consumption will practically not increase much. If you depend on the water of the Rhône or the water of the Ebro, the day they don’t bring water, what are you going to do?
Where should we best use resources? What misuse are we making of water? where do we lose a lot of water? Where can we rescue more resources?
The answer is the sum of several things. The fact that there are municipalities whose supply network loses more than 10% of water means that they are doing it wrong, because they have not invested in maintenance. It cannot be that there are municipalities that lose 40% of their water. Going below 10% is very difficult because the economic investment is very large and the return is very small. Zurich has reduced water losses to 5%. How? Investing, doing it with public resources without making users pay because the extra cost is important
And the industries?
The industry in Catalonia has done its homework quite a bit, consumption has dropped a lot. At this time I do not believe that there is excessive consumption of water by the industry in general. Many of them make non-consumptive use of water; That is, they can use it and then return it to the medium. They use it and do not consume it. Of course there are particular cases to review.
In Spain we have the problem of pig macro farms
We have the problem when more slurry than necessary is dumped on the fields and contamination of water reserves occurs due to excess nitrates. A very high percentage of the pigs that pollute the waters are raised here and then exported. Why do slurry pollute so much? Well, because they don’t treat each other well; However, we have had the solution to pollution for decades. The slurry can be accumulated in a digester on the farm. Thus, you obtain methane with which you can make energy; water, which you can recycle and reduce consumption; and residual sludge that, once treated, is a product that can be applied in the field, since you no longer throw away ammonia and do not contaminate the atmosphere. This way you solve three problems. What’s wrong? This is expensive. And there are lobbies that exert great pressure to continue the same. I hear those responsible for Livestock of the Generalitat without any concern about the environmental issue, only concerned about producing more meat.
How can we improve or obtain more water resources?
What is clear is that the focus cannot be the citizen who uses 100 liters of water a day, or less. And how can we go down, for example, from 100 to 80 liters/person per day? Here the reuse of water used in the home, in the kitchen, the sink or the showers that can go to the toilet tank is key. There are already systems of this type; The thing is that it is very expensive. An incentive policy is needed so that citizens can do this, as it would save 20% of water. I know of a case of a citizen who, with all this, limits his consumption to 33 liters / person and day from the network.
And how can you get even more water?
The first thing that comes to mind is rainwater. Large urban stormwater tanks (like those in Barcelona) are designed to retain water, which then goes to the treatment plant; But in times of drought, in 2008, there was already talk that when it rained this water could be made drinkable with a reverse osmosis system, which would allow for small localized water treatment plants, useful in certain neighborhoods.
What other proposals would you make?
-The urbanizations of Catalonia waste a lot of water, deplete aquifers, dry up fountains or the river itself. All urbanizations in Catalonia should have a plan that incorporates rainwater collection and solar roofs. Thus, when it rained, a good amount of water could be collected, so that for two months they could even make it drinkable and drink it.
Would it be a collective collection or on the roof of each house?
I believe that it is better to have this tank on each roof, that everyone has their own tank, as some town councils have begun to request that they include it in their regulations. The use of this water for supply is possible since it is easy to make it drinkable. With a filter and ultraviolet light disinfection, the water is safe to drink.
Advantages?
There are many urbanizations, and many are only used on the weekend. With this water, fewer sources and aquifers would dry up and a relevant amount of water would be available. Making a collective deposit is fine, but doing it individually helps raise people’s awareness. This could provide 15-20% additional resources.
How to address the problems of inefficiency of local supply networks? There are those who maintain that there has been a finger pointing to the city councils and others emphasize that collaboration between the ACA and the city councils should prevail.
What has happened is there are town councils that have done it well, for example Figaró or Terrassa, with control of leaks, savings and so on. But there are town councils that do not. Why? Because many town councils, in reality, do not know the water they use. When you want to know how much they consume, they refer you to the company. If you have a concession and do not control it, the company’s interest in making money will prevail. You have to look very carefully at the small print of the contracts. The ACA only draws attention to these municipalities.
The Ter Defense Group cannot analyze the quality of the water from the sources because they have dried up…
The sources are dry because there is less water due to less rain and because the trees are using more water (from the ground). Water management in Mediterranean Catalonia requires another forest management. In this drought the trees are dying since they compete with each other and none of them live well. With good forest management you eliminate a part of the biomass, there is less competition for water and you prevent trees from dying, ergo, you prevent fires. Forest management must be done to have more water in the rivers.
