Operation save the trees. The Barcelona City Council is fine-tuning its device to stop the death of specimens resulting from the drought. Today, the city has around 250,000 trees and palms of 487 species, and for now the Council is watering in one way or another around 85,500. This is one of the most important municipal challenges of recent times. Barcelona’s groundwater distribution system barely reaches 20% of the city’s green areas, and tanker trucks and vans don’t reach everywhere either.
Throughout their lives, here the trees and palms were only watered during the first four years of life. And then they always managed by themselves, with rainwater and underground water. A thousand botanists, gardeners, arboretum managers, conservation specialists and other technicians from the Institute of Parks and Gardens are now studying a scenario unheard of in these latitudes. It hasn’t rained as it should since the spring of 2020. And in the last ten months, around 2,000 specimens have already died due to the drought.
We went to Barceloneta park a few mornings ago. The rains of the last weekends refreshed the atmosphere, greened the damaged lawn, invited the children to jump over the puddles. But that was nothing more than a mirage. The rainfall barely penetrated the earth. Maybe they got 10 centimeters deep, in some places maybe 20, but the subsoil is still dry, hardened, barren. The roots continue to suffer.
The situation is so worrying that, if the earth is not enriched now, this summer, when temperatures soar, it will become catastrophic. No one knows how many trees will die. Due to the heat and drought, the trees slow down their activity in order to save water, so much so that they can collapse. Heat and drought can quickly turn into a deadly perfect storm. Operation save the trees is a race against the clock, the thermometer and the elements.
The problem is that Barcelona’s groundwater distribution network does not yet reach all corners of the city. Of the 85,500 trees that the City Council is watering against the clock, only 17,000 benefit from the system. That is why the City Council is also using these days tanker trucks with capacities of up to 20,000 liters wherever they have the appropriate access. Before the state of exceptionality, barely a dozen of these vehicles worked. For now, 14 in the morning, 22 in the afternoon and 10 more at night are working. About 45,000 trees are watered this way.
And up to 46 vans with tanks of just under a thousand liters go to the places most in need, such as Avinguda Diagonal, Plaça Francesc Macià, Barceloneta Park… in order to take care of 23,000 more copies . These shortages may ease a little next year. The Barcelona City Council is investing 14.4 million euros to be able to improve its phreatic water distribution system and that during 2025 the available volume will increase by 20%. We are talking about 200 million liters a year.
Cristina Vila and Francesc Jiménez, director of the Barcelona Water Cycle and manager of Parks and Gardens, say that after the previous drought the City Council did not stop investing in this network. In a normal situation, Barcelona used about three cubic hectometres of water for irrigation, 2.5 of which was potable and the rest groundwater. Imagine a block in the Eixample of the height of the W hotel. Well, roughly speaking, this volume is one hectometre.
And then, in an exceptional situation, consumption was reduced by 57.7% and became 1.27 hm3, 0.90 potable and 0.37 phreatic. At the beginning of February, the Generalitat established phase 1 of the drought emergency. Since then, the restrictions imposed only allow the City Council to do survival irrigation, as little as possible, and only with phreatic water, with water that is neither drinkable nor can be made potable. So that consumption is currently reduced by 71%, and it is 0.87 hm3 annually of water that people cannot drink.
In the Barceloneta park, the gardeners, with the hose in hand, water most of the trees, particularly profusely those that are arranged in the garden areas and more discreetly those that stand on the asphalt . This is not an arbitrary procedure. They explain that those in garden areas benefited for decades from watering lawns and shrubs, and in some ways got comfortable. The others, the ones planted on the asphalt, had to loosen up and develop their roots much more, and are now facing the drought in better conditions. Some need more watering than others.
And these days gardeners pay a lot of attention to the leaves, and also to the bark, to check how each one reacts. It is a tree-based care. The City Council has a file for each specimen in the city, and all its vicissitudes are collected there. And with all these observations, the technicians adjust these days the frequency and intensity of watering each specimen, those in the Barceloneta park and also those in the rest of Barcelona. Poplars and other riparian species accustomed to growing by rivers require a low head of water once a week, while oaks barely need to be watered once a month.
“It’s barely been three weeks since we applied the new procedures – say the municipal technicians, Vila and Jiménez -. We are still analyzing the reactions of the trees in this new scenario”. Because every detail counts. Many of the trees that are on the avenues that head towards the sea are in better condition than those that stand on the avenues from Besòs to Llobregat. And in fact, for some the old streams went down, and for others they didn’t.
“We hope that in two or three weeks the situation will be clearer – continue Vila and Jiménez-. Then we can see if we have to make sacrifices or not. The timing is exceptional, and we don’t know how the trees will react. We are watering specimens that we had never watered before, enriching their subsoil so that they can withstand the approaching summer. The most likely thing is that we have to adjust the frequency and intensity of watering. In addition, the sources that provide us with phreatic water are changing. We analyze them every fortnight to check the evolution of their salinity, to see if we have to resort to others. In any case, our goal is to save all the trees in Barcelona. It hurts us a lot every time someone dies.”
The Barcelona City Council estimates that in the last ten months around 2,000 specimens have died due to the drought. In principle, everything indicates that water stress has been the cause of most of the deaths.
But the drought is to the trees what the covid pandemic meant to people. Many are dying because the lack of water has left them so weak that they cannot face fungi and diseases that they would have been able to overcome in a normal situation.
It should be added that more than 700 date palms were cut down after one fell and killed a person in the Raval neighborhood in the summer. Many of the cut down palm trees were fine, but in the context of the drought, they aroused many concerns. In the end, safety was prioritized.
At the moment, the gardeners are taking special care of the largest specimens, because they have already grown and extended the branches that provide so much shade, that mitigate so much noise, that give us so much oxygen… Because the trees are part of the heritage of this city, because they make it a much friendlier and livable place. And if they are not taken care of now, in this delicate trance, people will discover what it really means to live in a cement city. If we lose the trees, it will take a long time to get them back.
