## 1 Introduction
### The Water Consumption in the Spanish Territory and Its Relevance to the Tourism Industry  
This study examines the intrinsic relationship between the abuse of water and the tourism industry as a vital resource and a tourist attraction [42]. The tourism industry consumes 1% of the global consumption of water, nothing compared with the 70% used by the agricultural sector or the industry sector, which reaches 19% [18; 43]. The tourism sector is a conspicuous consumer of water, especially by hotels, at all levels, such as spas, gardens, pools, golf courses, and cleaning and washing activities, amongst many others [44]. From 2018 to 2021, Spain was the second most visited country in the world [45] and represents one of the most important coastal sun and sand tourism destinations globally [46; 47]. Mass tourism takes place in Spanish tourist destinations where water is scarce to meet the demand [48; 49; 50], and therefore, it is necessary to resort to desalination [51]. Most people are not fully aware of the importance of water to life and its conservation because water is generally an undervalued resource. For this reason, this study tries to show the relevance of water as a vital source for humans and the economy across the globe. UNICEF [52] reported that 703 billion people lacked access to safely managed drinking water services in 2022, and this is another piece of data that confirms the need to conduct this research. A study carried out by [PERSON] et al. [18] revealed that tourists consume 300 L per day on holiday versus 160 L per day at home. The water consumption in Spanish hotels by tourists increases depending on the hotel's category and location, from 208 to 594 L per guest night [20; 53]. However, these figures are even more worrying for government bodies and residents. While the average water consumption of Spanish households was 133 L per inhabitant per day in 2022 [54; 55], the water consumption of a tourist is between 450 and 1000 L, depending on the season and Spanish region [56]. These figures are calculated based on the hotels, restaurants, theme parks, and municipal expenditures such as swimming pools, cooling and irrigation, kitchens, toilets, laundry, golf courses, saunas, and hygiene services [25]. UNWTO [57] noted that these figures of water consumption may reach between 2000 and 3423 L per day and room at hotels located in the tropical belt. For instance, on a special day and without water restrictions, the water consumption may be up to 899.5 L (see Figure A1 of Appendix A) by a Spanish person [31; 58]. This figure is very far from 20 L of the minimum daily supply of water per person that can cover the basic needs of personal hygiene and food according to the United Nations, known as the UN. To ensure the full realization of water rights, countries across the world should aim for at least 50 to 100 L per person per day [59]. In the end, tourists and residents alike require a safe and dependable supply of water for their daily activities, even though tourists demand more water than local residents [60]. Understanding the actual consumption of tourism water resources is vital to facing the water scarcity problem in Spanish destinations. Tourism aggravates tensions over the demand for water consumption between residents and tourists due to its scarcity, especially  
Figure 2: Average annual rainfall in Spain (1961–2022). Source. Our elaboration from [32]. Unit of measurement: litres per square metre. in the summer [14]. This study tries to stage the delicate situation of water consumption in the Spain tourist destination as we, as government bodies and researchers, must engage in resolving this situation and provide practical solutions in terms of sustainability, efficiency, and residents' quality of life and well-being. This implies that, from our research point of view, the availability of water for residents' consumption must be a permanent priority above the economic and commercial interests of the tourism industry.