Ciutadella, water chaos that could be made worse

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The Ciutadella Town Hall plans to increase the current extractions from the aquifer (which is nearly completely saline) by 30% and use the desalination plant  100% by 2031. GOB has submitted formal complaints about the so-called Sustainable Management Plan of water and the drought emergency, because it considers the plan to be unrealistic.

A saline aquifer

The Ciutadella aquifer is almost entirely saline, which is why a desalination plant was installed. However, the lack of a strategic vision and the resistance to paying for much more expensive water (desalinated water is about three times more expensive) means that they have continued putting pressure on the subterranean reserves. Now plans for urban growth are completely unfeasible with regard to water supply.

The situation is so alarming that the new General Plan has been held up because there are no ways to supply the planned population. The Sustainable Management Plan tries to be a document that serves to unlock urban growth. In the opinion of GOB, the proposal is unrealistic. Let us look at some of the data.

In Ciutadella there are 76 sanctioned water catchments. The authorised volume of 30 of these is unknown. In some cases, pumping is from dozens of meters below sea level, thus facilitating a large degree of marine intrusion.

To this situation is added the serious problem of security. Effectively, the water catchments for supplying water for the population should have a security perimeter fence of a kilometre where a series of activities and uses that may create health problems are prohibited. Many catchments in Ciutadella do not comply with this requirement though they are close to livestock farms or urban areas with conflicting industrial activities.

Unattainable growth

It has to be borne in mind that, currently, the municipality`s registered population of 30,811 inhabitants in 2022 increases seasonally to 66,466 in the month of August.

In 2021, the subterranean water supplied 76.2% of the total volume, while the remaining 23.8% was provided by the desalination plant. That is 8,685 m3 per day coming from the aquifer and 2,712 m3 per day coming from the desalination plant.

With the forecast proposed by the new planning, 40,900 people would be on the census in 2035, which estimates a population of 97,308 during the peak season.

In order to supply such a volume of people, it is estimated that, even by the summer of 2031 (that means in eight years’ time) the desalination plant would have to function at 100% of its capacity (10,000 m3 per day) and furthermore, complemented by the extraction of 12,500 m3 per day of subterranean water.

In other words, the Plan foresees that in the summer season there will have to be an increase in the aquifer extractions of nearly 30% with respect to the current amount. Given that the desalination plant, at full capacity, could supply only 44% of the necessary water, 56% would have to come from the subterranean catchments.

This added pressure that seems, in any case, impossible to realise if the current situation of the water reserves and their evolution is reviewed – stable or downwards – over recent years. Remember that the state of the 1901 M3 of the Ciutadella mass, from which 75% of the current extractions come, is negative in quantitative terms according to the current Hydrological Plan.

Purified waters cannot be reused

The current bad situation of the aquifer can be verified by the quality of the water that reaches the purification plants. In this respect, the southern treatment plant (where an irrigation pond was built) registers excessive salinity for the irrigation ditch during a large part of the year. In the northern treatment plant, the excess of salinity affects 85.5% of the flow. Therefore, the idea of recovering the aquifer by injecting water from the treatment plant or from the irrigation ditch is not viable.

The theory that has been used until now that the salinity will go down because aquifer water will be replaced by desalinated water is disproved in this Plan. The hope is to increase the extractions even more from the aquifer.

Neither irrigation systems nor rural areas have been taken into account

In the formal complaints made by GOB they warn, also, how the Plan has not considered the excessive irrigation that takes place in the municipality during the summer when huge quantities of water are extracted without any controls. Watering takes place even in direct sunshine and sends nitrates and pesticides into the aquifer. Nor have the 15 existing rural nuclei been considered.

As they are not considered, no measures have been taken to rationalize the extractions nor the consequent contaminations that have been found in different wells. (Watering can be restricted only in the case of droughts.)

Promote a plan for the recovery of the aquifer

According to GOB, the data that appear in the Sustainable Management Plan prove the absolute unviability for the forecast growth in Ciutadella. It is urgent to rationalise the uses:

    • Consumption must be reduced (as the population is at present, residents plus visitors, consumption is 286 litres per person per day).
    • Losses must be reduced (the distribution network loses 30% of the water it transports).
    • Irrigation must be controlled (intensive farming can require approximately 5,000 m3 per hectare per year).
    • Wells where there is extraction from a great depth must be closed, because they make the problem of marine salination worse.
    • Wells where there is a risk of contamination because there is no perimeter security fence must be closed.
    • There must be a plan for the recovery of the aquifer. This necessarily implies the reduction of the current extractions, not the increase.
    • Any growth that implies a larger population must be revised clearly to decrease growth, because not to do so will aggravate a situation that is already alarming.