Sustainability and water security in the Algarve

We really need, and as soon as possible, to think, study and start to implement a true Plan for the Sustainability and Water Safety of the Algarve

Previous point:
1) The characters in this story are fictional;
2) This writing was produced at the moment when we left the Elsa depression and entered another one, the Fabien, and when the meteorology, with regard to the absence of precipitation, alleviates a little, as we should not give our opinion under the maximum pressure of events already which tends to condition our objectivity.

Two friends, A and B, meet as usual at the neighborhood café table, while the rain and wind brought by Elsa make themselves felt outside.

It is one of those cafes like so many others, privileged places to debate the main topics of today. Between a dripping spout and a decaffeinated one, the following dialogue takes place.

A: Well, it seems that with what has already rained and is still going to fall, the drought in the Algarve is over. We will have the dams filled again and there is no longer any risk of running out of water in the taps.

B: Even so, I don't think it will be enough to replenish reserves either in dams or in groundwater. You already know that I am curious about these matters and even today I consulted the IPMA website.
The entire territory of the Algarve is still in severe meteorological drought and even a part of the Sotavento remains in extreme drought.
At least, the water content in the soil has already increased, with the entire region above 20% and in some cases even 50%, when a few weeks ago, in significant parts of the territory, this index was even below the Permanent Decaying Point, in other words, in these areas, neither spontaneous vegetation nor rainfed crops had the minimum availability of water to survive, even jeopardizing the natural biodiversity itself.

A: And the dams? How are your availabilities?

B: They are still well below historical storage averages, both in the Barlavento and Sotavento systems, in some cases still with values ​​below 30% of capacity.

A: From what you tell me, it's still not enough for us to rest easy! In other words, we really need to do something truly meaningful if we want to stop having the “creed in our mouths” all the time.

A: Not anymore! It is absolutely critical that we move forward with an Integrated Water Security Plan for the Algarve, otherwise, if we do nothing, we could be jeopardizing our environmental and economic-social sustainability.
And for that, all the options have to be considered, studied and submitted to a rigorous and impartial cost-benefit evaluation.
No alternative should be discarded a priori under penalty of detracting from such an integrated solution. Two things are, however, factual: without water it is not possible to carry out competitive economic activities in the Algarve, whether in agriculture, tourism, etc.
Even the traditional rainfed crops, today, with the worsening impact of climate change, have to be helped by irrigation other than in the first years of growth.
On the other hand, no matter how long it takes to implement these possible mitigating measures, any more year that we take to decide is another year that we are slow to achieve.

B: And do you think that even the construction of new dams, such as the ones we hear so much about (in the rivers of Foupana and Alportel), are investments to be considered?
If it doesn't rain enough, how are they going to fill these reservoirs, not to mention the inevitable negative environmental impacts associated with it?
You have certainly heard about the interruption that originates in the supply of sediments and nutrients to the coastal areas and which is sorely lacking for the recharge of the sands and for the feeding of marine species, among others.

A: They must also be taken into account. The Algarve, and its population and economic occupation, is not all the same, so this plan, as the epithet “integrated” indicates, has to contemplate more than one type of measure.
For example, did you know that the Ribeiras do Algarve watershed is mostly characterized by torrential regimes, that is, they are practically without water when it doesn't rain, as they fill up quickly, as we are now already seeing with these recent rains.
And this torrential regime tends to increase with climate change.
Therefore, if we do not reinforce the level of supply of this water, acting like the ant that hoards it in times of greatest abundance to guard against periods of greater famine, we will be very vulnerable to the occurrence of increasingly frequent episodes of water deficit.
We have to study, weigh and only then decide… on the other hand, as you are well aware, there is also the possibility of implementing measures to minimize and mitigate any negative environmental impacts associated with this construction.

B: What about the use of treated wastewater, ie, sewage treated by the WWTPs and which is rejected without any use for the natural environment, the desalination of seawater (and so much that we have!)?

A: All hypotheses to contemplate. Wastewater from WWTPs, especially new generation ones that already have more efficient treatment systems, and that will necessarily require additional ones to correct the high electrical conductivity (excess salts) and the bacteriological levels of pathogens - such as fecal coliforms - for parameters more in line with those legally required for these uses, with an adequate investment in the construction of dedicated networks for their distribution, they will necessarily be a good alternative for the irrigation of golf courses (in fact, we already have one in the Algarve to be used watered in this way) and of public gardens, for cleaning streets, etc.. even for the watering of permanent crops, such as fruit trees (avocado, orange trees,..., although in this case it is necessary to consider the high energy cost associated with the increase of these flows from the coast, where these WWTPs are located, to the barrocal, where most of the irrigated agriculture is practiced in the Algarve).
Properly treated wastewater can even be used for artificial recharge of aquifers. And this, my friend, is what makes the so-called Circular Economy happen.
The same reasoning applies to seawater desalination plants, even more so when the last solar energy auctions had such a significant price drop and we have such a high photovoltaic capacity in the Algarve, thus being able to promote desalination using energy sources renewable, therefore less impactful.
For some reason, we are so well known around the world as a sun and sea tourist destination.

B: I agree with you. And to these structural measures to strengthen supply, we must also add those related to combating water losses in low-water distribution systems managed by municipalities (in the order of 25%), in the remodeling of hydro-agricultural facilities, some still from the 60s of the last century, and that despite the investments already made, underway or planned, to reduce losses, they still need to improve the respective efficiency of distribution, as well as to raise consumers' awareness of the rational and parsimonious use of a increasingly scarce resource such as water (don't forget that Portugal is the 2nd country in Europe with the highest average consumption per capita, more than 190 liters/day -which is really a lot of water! - and the Algarve, by way of population associated with tourism, exceeds 240 liters/day/inhabitant), starting right away in schools – “it's the little ones that twist the cucumber” – but also betting on codes of good practice and on monitoring targeting of real consumption by large groups of users; and when simple awareness does not arrive, it is necessary to monitor and penalize the least responsible.
There is no doubt that we really need, and as soon as possible, to think, study and start to implement a true Plan for the Sustainability and Water Safety of the Algarve.
To stop being so hostage to randomness (or to Divine Providence, if you prefer) and to be able to face the future with a greater dose of predictability.

Pedro Valadas Monteiro is an agronomist and regional director of Agriculture and Fisheries