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Contract renewal with the incumbent is common practice in the contracting-out of public services. It could, however, affect competition by reinforcing trends towards market concentration. This article contributes empirical evidence on the determinants of the result of public tenders for the renewal of private provision of the urban water service. A dataset with information on 215 public tenders held in Spain between 2008 and 2019 is employed. The methodology is grounded in logistic regression techniques. The findings indicate that incumbents' size does not play a role in the proba-bility of alternating between service providers. Furthermore, competition−proxied by the number of bidders−and transparency in managing public tenders both increase the likelihood of alternating be-tween providers. Lastly, the estimates suggest that larger municipality size and discretionary power of entrenched political parties might also play a role in favoring incumbents' contract renewal.

This paper studies the dynamics of concentration in the Spanish market for the provision of urban water service by private contract operators in the 2000–2020 period. The market is highly concentrated. Concentration increased until 2007, at which point it started to decline when Law 30/2007 on Public Sector Contracts and Organic Law 8/2007 on Political Party Financing were passed; before rising again from 2016 onwards. This latter trend results from strategic behaviour by the two leading operators, acquiring smaller companies with a notable presence in some regional markets. Further legislative reforms aimed at safeguarding space for competition are thus proposed.

Communal water organizations are widespread in many areas of developing countries, where local governments lack the resources to offer a minimum quality water service. However, these organizations have their own resource limitations and they additionally face the well-known problems associated with collective action. It is therefore unclear how effectively they can provide safe water, and the evidence available thus far is mixed. This paper analyzes the communal water organizations in Peru known as Juntas Administrativas de Servicios de Saneamiento (JASS). Using detailed household survey data, we empirically assess the differential impact of the JASS vis-a-vis public systems on two water-related child health outcomes: diarrhea and low birth weight. Our identification strategy exploits the legislative changes introduced in the 2000s and the arbitrary cut-off to classify the administrative sub-units of Peruvian municipalities (districts) in order to achieve exogenous variation in the type of water provision. We find that child diarrhea and low birth weight are significantly lower for households served by JASS in the districts located in the first Inca settlements where the pre-Columbian tradition of communal work, called Minka, has survived over centuries. We also show that in those districts the JASS have better governance (existence of their own rules, higher participation and accountability and a greater ability to obtain external support). These findings confirm the hypothesis that social capital and traditions foster cooperation among community members and are in line with recent works showing the importance of historically developed institutions in building social capital. More generally, our results suggest that communal organizations are not a one-fits-all solution, but rather their success depends crucially on the existence of mechanisms for overcoming the problems associated with collective action and the active involvement of the community.

Due to lack of economic resources and the geographical dispersion of the population, state and private for-profit water provision is not feasible in many remote rural areas of developing countries. In such instances, community-managed water systems emerge as an alternative mechanism to provide safe water. Despite their importance, little is known about this type of organizations. This article examines the Juntas Administradoras de Servicios de Saneamiento (JASS), communal organizations that provide water services to more than 3 million people in rural and peri-urban areas of Peru. We focus on two important and related dimensions of the JASS. First, we empirically identify the factors associated to their existence (economic resources of the municipalities, tradition of communal work, and ethnic homogeneity). And second, we examine their organization and how they manage the water systems, which is importantly affected by the socioeconomic characteristics of the communities. Using the Peruvian JASS as a showcase, this article sheds then some light on the potential viability of this type of organizations. We conclude that the JASS might be an important and effective alternative to organize the provision of water services in rural and isolated areas. However, the consolidation of these institutions requires adequate supervision to ensure that water systems are correctly designed and managed and that internal governance problems do not compromise their sustainability.

De acuerdo con el RD 140/2003, el agua apta para el consumo humano no debe mostrar presencia de los indicadores bacterianos Escherichia coli, Clostridium perfringens y Enterococcus sp. Pero, aunque no se detecten estos indicadores, el agua del grifo no es estéril y puede tener cierta cantidad de microrganismos que muchas veces puede generar colonias en las placas de cultivo. Lejos de representar un peligro para la salud humana, si se dispone de un método rápido, sencillo, robusto y fiable para la identificación de estas colonias, se puede avanzar mucho en el conocimiento de la microbiología del agua potable. El proyecto Drinking Water Library ha permitido desarrollar la primera base de datos para MALDI-TOF MS específica para bacterias presentes en aguas de consumo.

This document provides an overview of how water resource software’s (WRS) are used to manage water resources issues, criteria for WRS selection, and a high level review of WRS currently available that central and state governments of India can use for water management. The water resource issues covered include water allocation and planning, flood management, groundwater management, conjunctive use, water quality, and sediment transport.

In order to evaluate and reflect the sustainability of services in the region, an overall sector sustainability assessment has been established taking into account four main dimensions: access to services, quality of services, efficiency of services, and financing of services. Each of these dimensions is measured through three simple and objective indicators. For each indicator, best practice values are established by looking at the best performers in the region, and countries closest to those best performers are deemed to have a more mature sector. A more complete description of the methodology to assess the sector sustainability is included in the Annex of the State of the Sector Regional Report from the Danube Water Program. The outcomes of this assessment for the Montenegro water sector are displayed, which also shows average and best practices in the Danube region. As a result, the Montenegro sector sustainability score is 59, which is below the Danube average sustainability of 64, and is among the lower scores in the region. The assessment shows that, on average, the country performs well in terms of access to piped water and flush toilet, continuity of service and affordability. The main deficiencies of Montenegro’s water sector identified through the sector sustainability assessment are the operating cost ratio, staffing level, and wastewater treatment coverage.

To evaluate and reflect the sustainability of services in the region, an overall sector sustainability assessment was done, taking into account four main dimensions: access to services, quality of services, efficiency of services, and financing of services. Each of these dimensions is measured through three simple and objective indicators. For each indicator, best practice values are established by looking at the best performers in the region, and countries closest to those best performers are deemed to have a more mature sector. A more complete description of the methodology to assess sector sustainability is included in the Annex of the State of the Sector Regional Report from the Danube Water Program. The outcomes of this assessment for the Ukraine water sector are shown in Figure 10, which also shows average and best practices in the Danube region. The Ukrainian sector sustainability score is 54, which is below the Danube average sustainability of 64. The assessment shows that, on average, the country performs well in terms of collection ratio and affordability. The main deficiencies of the Ukraine water sector identified through the sector sustainability assessment are investment level, wastewater treatment coverage, and nonrevenue water. The main sector challenges are: improving and clarifying the legal regulatory framework of the water sector; ensuring tariff setting according to the cost recovery principle to improve overall efficiency; and improving staff capacities and expertise.

In this numerical study, the cooling of exhaust gas issued from a rocket engine in a ground test facility has been investigated by solving the three-dimensional governing equations. Simulations have been performed by employing discrete phase model with plain-orifice atomizer to cool the exhaust flow effectively by injecting the coolant (water) in the form of a fine spray. The effects of coolant flow rate, inlet gas temperature, injection pressure, injector diameter, gas cooler length, and distribution of water droplets on the cooling characteristics, such as the temperature at the gas cooler exit, droplet diameter, and percentage of unevaporated water have been discussed in detail. Simulations highlight that optimum particle diameter needs to be identified for effective cooling, and also uniform cooling of the exhaust gas is attained by employing staggered injector distribution (more injectors at the periphery compared to the core region). Predicted values of static temperature and pressure agree well with the experimental data obtained from a scaled-down model high-altitude test facility. � 2014 American Society of Civil Engineers.

This report outlines a 3-year program to upgrade the knowledge platform for managing water resources in Central Asia. Its ultimate purpose is to enhance the ability of all countries to engage in evidenced- based dialogue on water and energy management. It focuses on regional actions, linking all five countries plus Afghanistan, but recognizes the essential role of national initiatives. It covers the core elements of a modern decision support system and, based on extensive consultations, supports a change in accessing, developing, and sharing information and analysis. The intended outcomes of the road map are to: (i) establish a knowledge platform that is accepted by countries as a basis for cooperative actions; (ii) enhance capacity and knowledge sharing at the national and regional levels; and (iii) directly improve management of water at national and transboundary scales.

This report presents insights from the FY11 review of the World Bank s water portfolio. The report includes a methodological section followed by reviews of four broad areas: the water related commitments managed by the World Bank Group (WBG) for FY011; the water-related commitments of the International Bank for Reconstruction and Development (IBRD) and of the International Development Association (IDA) for FY11; water-related projects approved in FY11; and analytic and advisory activities (AAA), in particular economic and sector work (ESW) and technical assistance (TA), delivered in FY11. The focus of the report is on the new IBRD and IDA commitments in FY11, which are analyzed not only based on data provided in the World Bank s project database but also with data generated by reviewing the Project Appraisal Documents (PADs) using a newly developed questionnaire. Some of the key findings of the FY11 review are the following: Water-related IBRD and IDA commitments comprised about 95% of the overall WBG managed commitments for water. From FY02 to FY11 they grew more than five-fold, from US$1.3 billion to US$7.4 billion largely driven by increased commitments for water supply and sanitation. In FY11 a total of 105 water-related IBRD and IDA projects were approved. Commitments by region were largest for the East Asia and Pacific Region (EAP) and the South Asia Region (SAR) with 30% and 29%, respectively. With regard to the number of projects, Africa was by far the leading Region with 33 projects. Of the 105 water-related projects, only 22% were mapped to the Water Sector Board (WAT) and most of these were water supply and sanitation projects.

[eng] Bottled mineral water has managed to become a commodity and can be found virtually anywhere in the world. However, even if it is a very common and well recognized product, little it is known about its history, about how, when and why it came to be. The origins of bottled water can be found in mid-19th century Europe and America, when spas started selling their waters outside their facilities. However, soon other springs which had not relation with traditional hydrotherapy started bottling their waters as well. Four conditionings have been found which explain why bottled water started being produced at that point in time and not before. Those factors are the existence of an adequate container, the invention of an efficient transportation method, a cultural/social predisposition and lack of salubrious water. When those four conditionings occurred at the same time, the bases for a thriving mineral water bottling industry were established. By exploring each of these factors in Catalonia for the period that has been found to encompass the first golden age of bottled mineral water (1840-1930), the general hypothesis is proven, meaning that all the aforementioned conditionings were necessary for the commoditisation of bottled water. Only when all those four factors took place at the same time it was possible to have a thriving mineral water business, not before. Accordingly, when in the 1930s some of those conditionings changed, the bottled market sector started a sudden downturn period, which did not stop until the all four factors coincided in time again., [cat] L'aigua mineral envasada ha aconseguit convertir-se en una mercaderia habitual que es pot trobar pràcticament arreu del món. No obstant això, tot i tractant-se d'un producte comú i reconegut, poc se sap sobre la seva història: com, quan i per què va arribar a ser el que és actualment. L'origen de l'aigua embotellada es remunta a l'Europa i l'Amèrica del segle XIX, moment en què alguns balnearis van començar a vendre aigua fora de les seves instal•lacions. No obstant això, aviat altres fonts que no tenien cap relació amb la hidroteràpia tradicional van començar també a envasar-ne. S'han descobert quatre condicions que expliquen per què l'aigua embotellada va començar a ser produïda en aquest moment i no un altre. Aquests factors són: l'existència d'un envàs adequat, la invenció d'un mitjà de transport eficient, la manca d'aigua salubre i una predisposició cultural i social. En coincidir aquestes quatre condicions en el temps, es van donar les circumstàncies perquè s'establissin les bases que desenvoluparien una indústria pròspera d'embotellament d'aigua mineral. Al mateix temps, en explorar cadascun d'aquests factors, s'ha trobat que la primera Edat d'Or de l'aigua mineral envasada a Catalunya va ocórrer aproximadament entre 1840 i 1930. En analitzar la hipòtesi general aplicada a aquest període i lloc, s'ha pogut provar la seva veracitat, la qual cosa vol dir que tots els condicionants abans esmentats són necessaris per a la comercialització de l'aigua embotellada. Només quan aquests quatre factors són coetanis és possible desenvolupar un sector d'aigua mineral envasada pròsper. En conseqüència, quan a la dècada de 1930 alguns dels factors esmentats van canviar, el mercat d'aigua envasada va entrar en un període de crisi que no es va aturar fins que les quatre condicions van tornar a coincidir en el temps.

Treballs Finals de Grau d'Enginyeria Informàtica, Facultat de Matemàtiques, Universitat de Barcelona, Any:2013, Director: Sergio Escalera Guerrero, Geographic Information Systems (GIS) are a key point for a water company. And with the introduction of new technologies have a very efficient tool to optimize their network. The aim with this project is turn the job more efficent. Furthermore, we promote the use of free operating systems such as Android, withi provide access to the technology to users. All this we will do by relying on two tools: a client application developed for Android devices and a Web Service to provide data to this application. Furthermore, Aigues de Castellbisbal want their Technical Area supervise the whole process. This is why the changes to be made in the client application will be pending for supervision of technicians.

This country note for Armenia is part of a series of country briefs that summarize information relevant to climate change and agriculture for three pilot countries in the Southern Caucasus Region, with a particular focus on climate and crop projections, adaptation options, policy development and institutional involvement. The note series has been developed to provide a baseline of knowledge on climate change and agriculture for the countries participating in the regional program on reducing vulnerability to climate change in Southern Caucasus Agricultural systems. This note for Armenia was shared with the government and other agricultural sector stakeholders and used as an engagement tool for a national awareness raising and consultation workshop, held in Yerevan in April 2012. Feedback and comments on the note from this consultation process have been incorporated into this updated version in collaboration with the Armenian Ministry of Agriculture.

Kosovo is a small and young state that gained an interim United Nations (UN)-administered status in the wake of the Dayton peace accord only in 1999; it declared independence in 2008. Compared to neighboring countries, it is still lacking in its basic infrastructure and its administrative and technical skills. In addition, with the onset of the War in Yugoslavia in 1992 most investment and normal maintenance came to a standstill. Much of the publicly owned infrastructure fell into disrepair or was vandalized, but private investments led to a construction boom which, however, is leading to many environmental problems. The government is committed to reconstruction and to the development of a peaceful state. It also intends to align with EU policies. Thus, the study has the specific objectives to: (i) assist the government to improve its river basin planning and management by providing (for demonstration purposes) a replicable tool and simulation model for integrated river basin planning and management; and (ii) support the government in its identification of priority measures of structural and non-structural nature to help strengthen the water resources sector performance. The source(s) for the financing of the identified projects will need to be identified further by the Government as the World Bank has not committed to involvement in the sector.

This paper provides an overview of major groundwater issues for Sub-Saharan Africa, with an assessment of their policy implications in terms of potential development and appropriate management. In terms of construction time, capital outlay and drought resilience, groundwater is the preferred source to meet most water-supply demands, despite hydro geological complexity, natural constraints on water well yields and quality, and institutional weaknesses. The 'new developmental agenda' relates to improving urban water-supply security and expanding irrigated agriculture to meet these challenges many countries need to undertake strategic assessment of their groundwater and prioritize investment on institutional strengthening so as to facilitate appropriately-managed groundwater development. Without effective use of available groundwater resources, improved livelihoods and climate-change adaptation will prove much more difficult to achieve.

This report discusses the key findings and recommendations emerging from a pilot Citizen Report Card (CRC) on water, sanitation, and sewerage services in Karachi. This initiative comes, on one hand, in the wake of deteriorating services, weakened community interfaces and accountability structures, poor revenue generation and dysfunctional governance structures and, on the other, an emergent consensus to bring in far-reaching institutional reforms that should move beyond financial and technical imperatives. The CRC, pioneered by the Public Affairs Center (PAC), Bengaluru, is a simple but powerful tool to provide public agencies with systematic feedback from users of public services. CRC gains such feedback through sample surveys on aspects of service quality that users know best, and enable public agencies to identify strengths and weaknesses in their work. A CRC on public services is not just one more opinion poll; it reflects the actual experiences of people with a wide range of public services. The survey on which a report card is based covers only those individuals who have had experiences in the use of specific services, and interactions with the relevant public agencies.

El objetivo principal de este trabajo fue determinar los factores ecológicos tanto microbiológicos como fisicoquímicos que permitan, favorezcan o indiquen la supervivencia y multiplicación de Legionella en los sistemas acuáticos artificiales. Con este fin se realizó un estudio de la prevalencia de las diferentes cepas de Legionella que se encuentran en las instalaciones hídricas de riesgo. También se analizaron parámetros fisicoquímicos y microbiológicos que podrían relacionarse y servir como indicadores de la presencia o ausencia del patógeno. Se analizaron parámetros como la temperatura, Fe, Cu, Zn y la presencia de biocidas. Con este estudio se pretendía conseguir un mejor conocimiento del comportamiento de la bacteria y su relación con otros microorganismos y determinados parámetros fisicoquímicos en estos ambientes, lo que permitiría un mejor control del origen de los brotes y como consecuencia una mejor protección de la salud pública. Para conseguir estos resultados: • Se realizó la estandarización de métodos, para el análisis y cuantificación de Legionella y protozoos en agua sanitaria. • Se realizaron muestreos de agua sanitaria caliente y torres de refrigeración que procedían de hoteles de la costa mediterránea y de residencias de gente mayor de la ciudad de Barcelona, con un alto grado de complejidad en el diseño y funcionamiento de sus sistemas de agua. • Se determinó la presencia de Legionella y su relación con heterótrofos a 22ºC, heterótrofos a 37ºC, Pseudomonas, Aeromonas y protozoos. • Se analizaron muestras y se asesoró sobre la desinfección de un edificio público de la ciudad de Barcelona con contaminación por Legionella, identificando los puntos de muestreo representativos y aplicando el método de cultivo y la técnica de PCR semi-nested puesta a punto previamente. Para posteriormente realizar las medidas de desinfección necesarias. • Se detectaron e identificaron amebas de vida libre en las muestras de agua sanitaria caliente y Torres de refrigeración aplicando técnicas de cultivo, observación con microscopio y PCR., The main objective of this project was to determine the ecological factors both microbiological and physicochemical, that indicate or contribute to indicate survival and multiplication of Legionella in artificial water systems. To this end a study of the prevalence of the different strains of Legionella found in water systems that presented risk was performed. The physicochemical and microbiological parameters that could relate to and even serve as indicators of the presence or absence of the pathogen were also evaluated. The parameters analyzed were temperature, Fe, Cu, Zn and the presence of biocide. This study aimed to achieve a better understanding of the behavior of the bacteria and its relationship with other organisms and certain physicochemical parameters in these environments, allowing better control of the source of outbreaks and consequently better public health protection. To achieve these results the following tasks were performed: • Standardization of methods for analysis and quantification of Legionella and protozoa in water. • Sampling of hot sanitary water and cooling towers from the Mediterranean coast hotels and elderly residences in the city of Barcelona, with a high degree of complexity in the design and operation of its water systems. • Determination of the presence of Legionella and its relationship with heterotrophic bacteria at 22ºC and 37ºC, Pseudomonas, Aeromonas and protozoa. • Analysis of water from a public building in the city of Barcelona with Legionella contamination identifying representative sampling points and applying the culture method and semi-nested PCR set-up previously. Following these analysis, disinfection assessment was provided. • Detection and identification of free-living amoebae in hot sanitary water and cooling towers using culture techniques, microscopic observation and PCR.

Recently, considerable attention has been given to the understanding of texture attributes that cannot directly be related to physical properties of food, such as creamy, crumbly and watery. The perception of these attributes is strongly related to the way the food is processed during food intake, mastication, swallowing of it and during the cleaning of the mouth after swallowing. Moreover, their perception is modulated by the interaction with other basic attributes, such as taste and aroma attributes (e.g. sourness and vanilla). To be able to link the composition and structure of food products to more complicated texture attributes, their initial physical/colloid chemical properties and the oral processing of these products must be well understood. Understanding of the processes in the mouth at colloidal length scales turned out to be essential to grasp the interplay between perception, oral physiology and food properties. In view of the huge differences in physical chemical properties between food products, it is practical to make a distinction between solid, semi-solid, and liquid food products. The latter ones are often liquid dispersions of emulsion droplets or particles in general. For liquid food products for instance flow behaviour and colloidal stability of dispersed particles play a main role in determining their textural properties. For most solid products stiffness and fracture behaviour in relation to water content are essential while for semi-solids a much larger range of mechanical properties will play a role. Examples of colloidal aspects of texture perception will be discussed for these three categories of products based on selected sensory attributes and/or relevant colloidal processes. For solid products some main factors determining crispness will be discussed. For crispiness of dry cellular solid products these are water content and the architecture of the product at mesoscopic length scales (20-1000 μm). In addition the distribution of water at mesoscopic length scales was found to be important. For semi-solid foods, sensory characteristics as spreadability, watery and crumbliness are primarily determined by food properties at mesoscopic length scales. Crumbliness is directly related to the formation of free running cracks that occur during eating of the product. Exudation of the continuous liquid phase of gels during compression gives rise to watery/juicy sensory attributes. For liquid food products, colloidal interactions of emulsion droplets, particles, proteins, and polysaccharides with saliva and oral surfaces were found to affect texture characteristics as creaminess, fattiness, roughness and astringency. © 2009 Elsevier B.V. All rights reserved.

Recently, considerable attention has been given to the understanding of texture attributes that cannot directly be related to physical properties of food, such as creamy, crumbly and watery. The perception of these attributes is strongly related to the way the food is processed during food intake, mastication, swallowing of it and during the cleaning of the mouth after swallowing. Moreover, their perception is modulated by the interaction with other basic attributes, such as taste and aroma attributes (e.g. sourness and vanilla). To be able to link the composition and structure of food products to more complicated texture attributes, their initial physical/colloid chemical properties and the oral processing of these products must be well understood. Understanding of the processes in the mouth at colloidal length scales turned out to be essential to grasp the interplay between perception, oral physiology and food properties. In view of the huge differences in physical chemical properties between food products, it is practical to make a distinction between solid, semi-solid, and liquid food products. The latter ones are often liquid dispersions of emulsion droplets or particles in general. For liquid food products for instance flow behaviour and colloidal stability of dispersed particles play a main role in determining their textural properties. For most solid products stiffness and fracture behaviour in relation to water content are essential while for semi-solids a much larger range of mechanical properties will play a role. Examples of colloidal aspects of texture perception will be discussed for these three categories of products based on selected sensory attributes and/or relevant colloidal processes. For solid products some main factors determining crispness will be discussed. For crispiness of dry cellular solid products these are water content and the architecture of the product at mesoscopic length scales (20-1000 μm). In addition the distribution of water at mesoscopic length scales was found to be important. For semi-solid foods, sensory characteristics as spreadability, watery and crumbliness are primarily determined by food properties at mesoscopic length scales. Crumbliness is directly related to the formation of free running cracks that occur during eating of the product. Exudation of the continuous liquid phase of gels during compression gives rise to watery/juicy sensory attributes. For liquid food products, colloidal interactions of emulsion droplets, particles, proteins, and polysaccharides with saliva and oral surfaces were found to affect texture characteristics as creaminess, fattiness, roughness and astringency. © 2009 Elsevier B.V. All rights reserved.

[cat] L'article traça els inicis del debat contemporani de l'oferta d'aigua i la seva qualitat en la Regió Metropolitana de Barcelona (en endavant, RMB), concretament en l'àrea del Vallès Occidental a partir del moment que aquesta comarca és conceptuada pels poders públics i els propietaris com a mercat d'aigües per a Barcelona. A partir de la constitució a Sabadell el 1912 de la societat de venedors d'aigua anomenada Liga de defensa de las Aguas del Río Ripoll y de sus afluentes y derivados, analitzem l'il·lusori optimisme tecnològic hidràulic que passava per la construcció del pantà al riu Ripoll i l'intent de tancament d'aquest riu en el seu curs alt, la qual cosa comportava en la pràctica el sacrifici ecològic d'un curs fluvial d'una longitud de gairebé 40 quilòmetres. L'episodi queda emmarcat en la lluita pel control del recurs aigua des d'una perspectiva de conflicte per sobreexplotació privada en perjudici de la comunitat, just en el moment històric en que es consolidava la política de demanda-oferta i el monopoli de l'actual empresa subministradora més important de la RMB., [eng] This article outlines the origins of the current debate on water supply and its quality in the Barcelona metropolitan area, focusing on the Vallès Occidental region, from the moment when both the authorities and private owners began to regard this region as a likely water market for Barcelona. Starting from the foundation in Sabadell in 1912 of an association of water suppliers by the name of Liga de defensa de las Aguas del Río Ripoll y de sus afluentes y derivados, we analyse the delusively optimistic (in terms of hydraulic technology) plan to build a reservoir on the Ripoll river and to dam its upper course, with the attendant ecological sacrifice of a fluvial course of almost 40 km length. This episode is placed within the framework of the fight to control water resources and seen from the perspective of the conflicts caused by private overexploitation to the detriment of the community, at the very time when the to this day most important supplier in the area was consolidating its supply-and-demand policy and its present monopoly.

La conciencia social sobre la problemática del agua no es de aquí ni de ahora. La preocupación por su existencia es igual, podríamos afirmar, a la misma existencia del hombre. El Mediterráneo en general y España, en particular, presentan una preocupación constante a 1o largo de su historia por el tema del agua.