We are in an important episode of drought, where the current reserves of the reservoirs of internal basins in Catalonia (Spain) are at 33,6%, when 1 year ago they were 63,3%. Throughout this year 2022, the number of operating units in which the alert has been declared has increased, to the point that most of the region is currently in this state of drought, with the recent incorporation of Darnius-Boadella and, above all, the area of Ter-Llobregat, which is where the largest number of people in Catalonia reside.
Bearing in mind that water is an increasingly scarce resource, the Catalan Water Agency's planning for the current planning cycle (2022-2027) envisages a significant increase in non-conventional water resources, especially those from desalination plants and ERAs (Water Regeneration Stations). Regenerated water is the resource obtained by applying a more advanced treatment to water already purified in an ERA so that it reaches the levels required for its subsequent use.
The reuse of regenerated water in Catalonia reached 53 hm3 in 2021, and it is planned that, at the end of the new planning cycle (on the horizon of 2027), Catalonia will reach 100 hm3/year of water regenerated.
In this climate crisis scenario, the European NextGen Circular Water Solutions project was developed between July 2018 and this November. This project has a budget of €11.344.256,56, and a contribution from the EU of €9.965,230,51, it is led by the KWR research center of the Netherlands, and the Catalan Agency of Water, Eurecat and ADASA Systems has collaborated.
This project has designed 10 case studies in 8 European countries to analyze the reuse of regenerated water, energy and materials. In the case of Catalonia, the Costa Brava was chosen, characterized by a high seasonal water demand, frequent episodes of water scarcity, also causing saline intrusion.
Specifically, the pilot plant was built within the ERA of Tossa de Mar, with the aim of analyzing circularity in the vector water and materials. It has been verified that it is possible to reuse the reverse osmosis membranes that are used in desalination plants to obtain quality water that meets all the requirements of the strictest legislation on water reuse material, the RD 1620/2007, and in particular Quality 1.1., which corresponds to the private use of garden irrigation or the discharge of sanitary appliances.
These membranes are a waste at the end of their useful life in a seawater desalination plant for the production of drinking water, but after a regeneration process they can continue to produce high quality water for other uses. A new membrane has a cost of €900, while recovering these membranes has a commercial cost of €400 and has been much lower in the case of the NextGen project.
Those responsible for the project wanted to go beyond current legislation, and the project has monitored more than 200 substances called "emerging pollutants" that may be regulated in the future because they can be found in water in very low concentrations (1 million times less than the classical measurement in milligrams per liter).
In recent months, two project meetings have been held with the participation of the majority of partners. The first was held in Barcelona in June, while the project closed in Athens on October 20-21.
Beyond the follow-up of these 10 case studies, an analysis of the life cycle and costs of the different associated technologies has been carried out, both current and ongoing legislation has been assessed for the identification of challenges, and a road map has been presented to be able to establish strategies to respond to these challenges.
In the social aspect, co-creation activities have been carried out with different interested people and entities ("stakeholders"), as well as activities to understand the current level of social acceptance, and an Augmented Reality application has been developed and a "Serious Game" application to simulate the integral water cycle and to estimate the amount of water that can be regenerated, visually and interactively. We have also worked with new business models that have allowed the creation of two "spin-off" companies.
As a final conclusion, to say that at a technical level we are capable of regenerating water, materials and energy more and more efficiently, but an important legislative and social impulse is needed. Legislation on reclaimed water in Spain dates from 2007 and in Greece from 2011, while the European Directive will not come into force until June 2023, the Regulation approved only for agricultural irrigation. Until now the North of Europe has not had the need to regenerate water, but the effects of climate change and recurring drought may contribute to a change regarding this very important tool in our home.