1. Introduction
The notable increase in water consumption for urban and tourism-related uses on the European Mediterranean coast mainly began in the 1960s and 1970s, reaching its highest peaks in the late 1990s and early 2000s [
1]. This rise in water consumption can be explained by the increase in homes and population numbers recorded for this coastal region, which is linked to the growth of tourism, as well as residential and service activities [
2,
3]. To a great extent, the increase in the urban and residential surface area is based on expansive urbanization and the creation of new urban spaces, such as gardens and swimming pools [
4,
5]. This process is typical of the majority of the Mediterranean coastline in France, Italy [
6], and Spain, including the Balearic Islands [
7] and the Costa del Sol [
8]. Low-density urbanization has also spread into other areas, such as Florida (USA) [
9] and Australia [
10].
Different types of urbanization are linked to residential activities, and they are based on the building, sale, rental, and the fitting-out of second homes, all of which have been characteristic of the Spanish Mediterranean coastline since the property bubble burst in 2007–2008 [
11,
12]. In contrast to the concentrated, high-rise model typified by the building of apartment blocks, residential expansion has primarily been based on the spread of new urban residential low-density types of models (single-family homes with a pool and garden) [
13], medium-density (semi-detached houses), and high-rise buildings (apartments), both largely integrated into private developments with a shared garden and a pool [
14]. Between 1992 and 2000, a total of 1.2 million homes were built on the Spanish Mediterranean coast, with 5 million more built between 2001 and 2011, an increase of 25% [
15]. A total of 345,410 new homes were built in the province of Alicante (where the study area is located) between 1997 and 2008, behind only Madrid and Barcelona, and higher than provinces with greater demographic weight, such as Valencia and Malaga [
13]. The drop in the pace of construction in Spain has been so marked that between 2009 and 2014 only 1,039,035 homes were built in the country as a whole. With regard to the province of Alicante, only 12,128 new homes were built after the start of the economic crisis [
16]. The fall in sales and purchases of homes is reflected in the housing stock figures, which in Spain in 2014 amounted to 439,617 homes, and 29,480 for Alicante (6.7% of the national figure) [
17].
Studies conducted in various countries in northern and central Europe [
18,
19], California (USA) [
20], and Mediterranean Europe [
21,
22,
23] show certain differences in their distribution that are linked to social, economic, sociological, and environmental factors. The study carried out by Domene and Saurí [
24] in the Metropolitan Area of Barcelona (Spain) showed that internal water use in apartment blocks equated more or less to the following uses: toilets and taps (basin) were a main domestic usage, at 29%–34%, followed in second place (although sometimes in first place) by personal hygiene (bath and shower) at 22%–34%, and with slightly lower percentages for laundry (14%–17%) and washing dishes (6%–12%), which were in third and fourth places, followed by drinking water and food preparation (5%–10%), and other uses (3%–5%). In addition to these, there are also external forms of water use, which vary greatly depending on the type of housing (semi-detached homes with shared gardens and pools, or single-family houses) and the predominant type of garden (Atlantic or Mediterranean), as well as uses included in the concept of others, which would entail leakages, among other elements. A garden is an urban environment that is of great interest to the scientific community, as the presence of green areas stands for a considerable increase in water consumption [
25,
26,
27]. In Australia, for example, Hurd [
28] concluded that watering the garden accounted for more than 50% of the total amount of water used in the home. In Spain, the presence of elements outside the home and their repercussion on water usage is also reported, as indicated in studies carried out in the Metropolitan Area of Barcelona [
24], Girona [
29], and on the coastline of Alicante [
14,
30,
31].
In the last decade, a mistaken perception was commonly held that an increase in the number of homes should be associated with a rise in water consumption, when in fact it led to a drop in the water consumption of most large urban agglomerations in developed countries [
32,
33]. The drop in domestic water usage from the mid and late 1990s is a general dynamic affecting most European countries. In Germany, for example, consumption levels between 1994 and 2004 dropped by 13%, reaching an average daily consumption per inhabitant of 126 L [
18]. Higher amounts have been reported in Denmark, where the drop between 1989 and 2008 reached 22% [
19]. According to the latest survey on the Supply and Treatment of Water in Spain, average water consumption in Spanish homes in 2005 was 255 L/inhabitant/day, 23% less than in 2012, at 198 L/inhabitant/day [
34]. In the Region of Valencia (Spain), where the province of Alicante is located, in 2012 water consumption per inhabitant/day was 202 L, a fall of 16% compared to 2005. For other Spanish cities, for example, water consumption is 133 L/inhabitant/day in Madrid, 116 L/inhabitant/day in Barcelona, and 119 L/household/day in Valencia. In contrast, these levels are much higher in other cities around the world, such as Jerusalem (650 L/inhabitant/day), Sydney (206 L/inhabitant/day), or London with 154 L/inhabitant/day [
35]. This trend can be explained by the combination of diverse factors, which include greater citizen awareness with regard to saving water, episodes of drought that translate into lower usage levels, social and demographic changes, higher water prices, more efficient technologies used in taps, toilets, showers, and kitchen appliances, the effects of the 2007/2008 financial crisis, and the processes of restructuring urban economies over the domestic, industrial, and commercial use of water [
36]. In this respect, a study by Deoreo and Mayer [
37] in the USA on interior uses in single-family homes concluded that water consumption had fallen since 1995 and that, furthermore, the trend was expected to continue as new technologies for saving water came on to the market. It also showed that one element to take into account was the economic recession that began in 2007/2008, which had contributed to the aforesaid drop in water use.
Exploring the determinants of water consumption requires consideration of the effects of tariffs and income, but also of many other factors, such as weather conditions, geographical or population characteristics, and household features [
23]. Beyond the traditional variables analyzed in the literature (e.g., weather, geographical location, household features), scant attention has been dedicated to variables, such as water utilities ownership, that could affect household water consumption [
38]. Further research is needed on the role of utility ownership because it remains unclear whether changes in governance toward a larger presence of non-public actors have by themselves led to improved water-conservation practices and, therefore, to reductions in water consumption [
32]. This lack of clarity is due to the fact that reductions in water consumption seem to affect cities with different systems of water ownership and management [
23].
In Alicante, the political ecological process that has radically transformed the country’s water environments follows the classic modernization path: from the dams and reservoirs that allowed the expansion of irrigation and hydroelectricity in the 1940s and 1950s to the inter-basin water transfers that added water flows for urban and mass tourist growth in the Mediterranean areas of the 1960s and 1970s. After this period, the most recent development is the construction of desalination plants responding to the new water demands linked to an increase of outdoor water use, associated with the real estate bubble of the 1990s and 2000s [
39]. It is during this last period that the expansion of new urban environments (gardens and pools) must be placed as perhaps the most recent beacon of urban modernity in the country. However, the collapse of the real estate market from 2007/2008 onwards and recurring climatic hazards such as droughts combine to check water-based urban growth in such a way that threatens the very fabric of urban modernity. Besides, Alicante is one of the fastest growing regions of Southern Europe in terms of residential tourism and also one area subject to periodic water crises due to the combination of recurrent droughts and expanding agricultural, urban, and tourist water demand.
This paper aims to contribute to increase the knowledge about water consumption trends in urban areas and their causes by focusing on the case of Alicante, on the Southeastern Mediterranean coast, and one of the Spanish cities where the development and the implementation of new water technologies is more intense. In this sense, according to the World Bank, in 1953 Alicante became the first international example of a successful water company of mixed (public and private) capital under the name of Aguas de Alicante. Tourist activity, and particularly residential tourism, has led to a change in the urban and demographic model of towns along the European Mediterranean coastline. The city of Alicante is a clear example of this. The climatic characteristics make it one of the most arid places in Spain, the common episodes of droughts [
40] and the recent decrease in water consumption [
41] explain the interest in this case study. This significance is accentuated by the fact that there are very few studies that analyze the relationships between water consumption trends and their causes in the study area.
The objectives of this research are: (a) to analyze and characterize the trend in domestic water usage in the city of Alicante; (b) to identify the factors affecting the current water consumption trend; and (c) to determine relationships between water consumption and the types of housing, the districts, and the socio-economic factors of householders.
This paper is organized in the following way. After the introduction, the study area and methodology are presented, followed by the results section, which discusses the work methods used in the research, together with the water consumption trends in the city of Alicante. The focus is then narrowed down to analyze the trend in water usage in the city of Alicante, by dividing household consumption figures according to the type of housing and the income level. Finally, the discussions and conclusions sections set out the reasons behind the water consumption levels in different homes in the study area.
2. Study Area and Methodology
Tourist activity, and particularly residential tourism, has led to a change in the urban and demographic model of towns along the European Mediterranean coastline [
5]. The province of Alicante, and more specifically its coastline, is a clear example of this. The climatic characteristics make it one of the most arid areas in Spain [
42], with an average rainfall of 356 mm/year in the city of Alicante [
40]. The avid implementation of expansive housing types since 1960, the predominance of a foreign population from central and northern Europe, which in some of the province’s coastal towns can account for 70% of the total municipal population [
43], and the income levels [
44] explain the interest in this particular area. The varied economic dynamics accentuate the complexity of the various factors that affect urban demand. The make-up of the city and its varied housing types explain the reason why Alicante was chosen. According to the latest census (2011), the city of Alicante has 329,325 inhabitants (17.02% of the total for the province), and 186,516 households (14.03% of the total for the province).
Consumption trends for the city of Alicante as a whole were identified for the period between 2000 and 2013. A local scale analysis provides for an in-depth study of the relationships that are established between the uses and the levels of income according to the neighborhood and the type of housing. These periods were chosen due to the interest in analyzing the recent evolution of urban usage levels in an area, which in that period, recorded a major increase in urbanized surface area and a spread of expansive housing types, followed by a significant collapse in the urbanizing process. The increase in urbanized surface areas and the types of housing highlight the relationships that exist between both factors and water demand.
The information used in this research was provided by the company Aguas Municipalizadas de Alicante, Empresa Mixta (AMAEM). It analyzed domestic water consumption according to urban typology, because this consumption is different due to the kind of urban model, the presence of urban nature, and socio-economic factors. Four urban typologies have been distinguished:
Urban core: compacted houses without outdoor elements
Blocks of apartments: houses with a garden and a pool in a condominium
Semi-detached houses: houses with a small single-family garden with a garden and a swimming pool in a condominium
Detached houses: houses with a single-family garden and a swimming pool
Using real consumption data for homes (2007–2013) divided into each housing type (urban core, apartment blocks, semi-detached and detached houses) in Alicante is an innovative element in the methodology used to analyze usage trends. Unlike studies based on estimates from different national bodies (INE) or results from interviews [
45,
46], in this study actual empirical data were analyzed, thus enabling a more detailed study to be carried out on the relationships that exist between the types of housing and the socio-economic characteristics of their inhabitants, and of other situational and structural factors that affect the usage of urban water. Due to the difficulty and complexity in accessing real data on water consumption in Spain, this research represents significant progress in the knowledge of water consumption behavior in this part of Mediterranean Europe, as it is based on real supply and billing data, and not on estimates of demand.
In the city of Alicante, consumption units were identified and selected by means of field work carried out to verify the different housing types that were predominant in each neighborhood. Once these housing types were identified, they were subdivided according to the income levels. To obtain this information, the socio-economic study of the city of Alicante [
47] was consulted, where the districts are broken down by economic income. Four income thresholds were established: low, lower-middle, middle, and high income, with respective limits of 25,000 €, 50,000 €, 100,000 €, and more than 100,000 €/year. Moreover these districts were analyzed taking into account the inhabitants ratio per house and the average age of the people in these houses according to the data provided by the Council of Alicante.
According to these three factors, 2800 real billing figures (households) were compiled from among the city’s 41 districts (
Figure 1). Previously, the water company had provided 11,480 real bills, although 8680 bills were rejected because they did not have any representatives due to the changes in owners, the existence of tenants renting houses, etc. In this regard, the technicians of the company selected correct bills for this study. From these districts, housing types were identified and they were differentiated by socio-economic features and differences in income levels in the same housing type (
Table 1). The make-up of the population and the housing types means that water consumption can be studied in terms of these urban and socio-economic differences. The choice of analysis units was based on the representation of housing types and different income levels.
4. Discussion
There are several reasons why the consumption of drinking water in the city of Alicante increased up to the mid-2000s. A primary factor was the expansion of new areas of residential and tourist use, and the strong dynamic economic situation recorded in the area from the mid-1990s. Alicante benefited from land development in the Region of Valencia, which was brought about by traditional industries, tourism, commerce, administration and services, export agriculture, and the boom in property development and building houses [
76]. In addition to this, there was the demographic growth due to foreign immigration and the major expansion of residential tourism [
77]. As a result of this economic and social dynamism, which was highly dependent on water usage, the province of Alicante developed an increasingly central position as a competitive area within the Mediterranean Arc, ranking fourth in Spain, behind Madrid, Barcelona, and Valencia for employment figures, and in fifth place in 2015 for its gross domestic product.
In 2004, the period of growth in water consumption that had begun in 1997 came to an end, once the intense drought of 1992–1996 had been overcome. The general dynamic of the drop in domestic water use since the 1990s can be related to structural factors.
The reduction in water consumption has been one of the measures taken by families to reduce their expenses due to the increase of water pricing and the effect of the economic crisis since 2007. A second consequence of these factors has been the intensification of the inter-relationship between the three aforesaid structural factors. Implementing technical measures and the progress made in new personal water-saving habits began back in the mid-1990s, and were prompted by the intense drought of 1992–1996. Since then, they have become commonplace, although they were intensified further by the related effect of the 2005–2009 drought and the economic and financial crisis that hit in 2007. Technological innovation barely counts when it comes to the reductions in consumption in marginal and degraded districts with a high percentages of immigrants. This is unlike households with middle and high incomes, where these improvements are a structural cause for reduced water expenditure, where traditional taps have been replaced with mixer taps and new models of domestic appliances. It takes time for these innovations in appliances and tap fittings to reach low income households, where the prolonged and intense nature of the current crisis often has traumatic consequences due to the high level of unemployment and severe cutbacks in income, which are undoubtedly the main cause of the drop in drinking water consumption. A third effect is the reduction of the occupancy of dwellings [
63,
78,
79]. On the one hand, this is associated with holiday homes, where the economic crisis has led to a reduction in the traditional holiday periods. On the other hand, many buildings and dwellings built during the last real estate bubble have not taken out the expected contracts for drinking water supplies. This has led to a decrease in water consumption in these dwellings, thus emphasizing their highly seasonal nature, which is concentrated into the summer months, with holidays now being significantly shortened due to economic factors. In turn, the effects of the economic crisis have been felt particularly in non-domestic uses, which on a whole have led to a 25% reduction in water consumption [
1]. This trend is more obvious in the commercial, catering, and services sector, and it has forced many businesses to close, and others to take drinking water-saving measures.
Besides, in terms of the socio-demographic agents, one aspect to explain is less demographic growth. During the period 2005–2013, the population in Alicante grew by 15,187 inhabitants, compared with a growth of up to 41,830 inhabitants in the period 2000–2005. This demographic trend is also related to the issue of settlement and more specifically to the slow-down of the urban residential expansion that took place from 2004 and 2005, which was followed by a complete paralysis of the real estate business from the outset of the financial crisis in 2007 [
11]. Moreover, it is important to point out that the estimated population loss in the province of Alicante was around 27,673 inhabitants in 2014 [
80].
These results could be compared with others in the Mediterranean European Area such as the study conducted by Romano et al. [
23]. In this regard, the aim of this study was to estimate the determinants of residential water demand for the chief towns of every Italian province (2007–2009), using the linear mixed-effects model estimated with the restricted-maximum-likelihood method. Results confirmed that the applied tariff had a negative effect on residential water consumption and that it was a relevant driver of domestic water consumption. Moreover, income per capita had a positive effect on water consumption. Among measured climatic and geographical features, precipitation and altitude exerted a strongly significant negative effect on water consumption, while temperature did not influence water demand. Besides, data showed that small towns, in terms of population served, were characterized by lower levels of consumption. Water utilities ownership itself did not have a significant effect on water consumption, but tariffs were significantly lower and residential water consumption was higher in towns where the water service was managed by publicly owned water utilities. Also, another study in Greece conducted by Panagopoulos [
22] proposed an innovative approach methodology in the international literature, to handling urban water consumption data in order to analyze statistically the interrelationships among the determinants of urban water use. Factor analysis of demographic, socio-economic, and hydrological variables showed that total water consumption in Mytilene is the combined result of increases in income, population, connections, and climate parameters. On the other hand, the water demand was influenced by variations in water prices but with different consequences in each consumption class. Increases in water prices are faced by large consumers in that they then reduce their consumption rates and transfer to lower consumption blocks. In this sense, these shifts were responsible for the increase in the average consumption values in the lower blocks despite the increase in the marginal prices.
5. Conclusions
The main conclusion drawn is that the installation of new appliances, saving devices, increase of environmental awareness, the price of water, and the use of reclaimed water for watering private outdoor and public areas have had considerable effect on the drop in domestic water consumption in the city of Alicante. Also, the economic crisis has had an effect on the drop in domestic water consumption in the last years, but this has not been the main cause. Perhaps if the current economic situation changes in the next few years, this may result in an increase in water expenditure, or in contrast, usage levels may stabilize as a result of well-established personal saving habits and due to the use of domestic appliances that are more efficient in terms of how they use water. It should also be pointed out that if the building sector recovers, an increase in the supply of municipal water can be expected, due to the increased number of homes connected to the network and the population covered.
A proper understanding of the factors that influence domestic water consumption is essential to develop and implement appropriate policies with regard to this resource. Among these factors, prices and taxes have been paid considerable attention to in the past, whereas demographic and cultural variables are still quite untouched. Economics has traditionally dominated the scientific literature on domestic water consumption. From the economic perspective, water is generally considered to be an inelastic good, since it cannot be substituted, and users do not tend to perceive this resource as being too expensive. A current example of this can be seen in California where its inhabitants have to reduce water consumption by 25%, if not there is the threat of heavy fines, along with an unprecedented state of emergency with the present drought there.
Perhaps the most important lesson to be learnt from the case of Alicante is the repercussion of the improvement of new technologies, the increase of water prices, the use of alternative water resources, and the different urban typologies on water consumption produced by outdoor residential uses. The expansion of the residential and tourist population, encouraged for decades by different administrations, has brought about strong competition with other economic (agriculture) and environmental (wetland) functions for the use of land and water. In low-density developments, i.e., single homes with a single-family garden and swimming pool, water consumption associated with outdoor areas is quite high. This is mainly due to the exclusive nature of its use by their owners. Urban typology that consists in condominium and apartment blocks would therefore stand for a more responsible and sustainable use of water resources associated with leisure. In this sense, it is important to study and analyze the growth of the urban sprawl on the coast of Alicante, due to its impact on water consumption. For this reason, in this dry region, urban typologies are a main element to account for in planning water resources in future scenarios. In this way, Alicante is much like other tourist areas of the world with lack of water resources, such as some regions of Mediterranean Europe, Australia, or the USA. A better understanding of the relationships between water consumption, urbanization, and the measures for reducing water demand would help to improve the knowledge of the changing nature of urbanization in areas where sprawling urbanization has become widespread, and it would help us understand the environmental impacts of this sprawl. Additionally, it is important to increase the knowledge of water consumption to account for the consequences of climate change and the increasing frequency of serious droughts and the general lack of water resources. This is one result that should be taken into account in the planning of future European urban areas.