The “Mar Menor” is an inland lagoon situated at the south of Spain in Campo de Cartagena within the region of Murcia. Its 135 km2 extension and a depth of 6 meters make it one of the largest salt lagoons in Europe. The lagoon, separated from the Mediterranean sea by a narrow land strip of 22 kilometers long and between 100 and 800 width, has a rich and diverse ecosystem as well as important cultural values. The “Mar Menor” and its peripheral humid areas count with different figures of protection such as Ramsar convention or the Barcelona convention for the protection of the Mediterranean Sea. Moreover, bordering the lagoon there are two protected natural spaces under the figure of Regional Park: “Arenales y Salinas de San Pedro” and “Calbalanque, Monte de las Cenizas y Peña del Águila”. Despite all of these protections the lagoon faces a serious environmental crisis. From the 1960s onwards the area has been subjected to a progressive process of touristification and urbanization that have risen exponentially the demographic and environmental pressure over his ecosystems. Several engineering projects have been taken place. In 1970 a sports port was built-up and was the starting point of a set of physical changes that will affect the lagoon and its surroundings. In 1973 another project was developed in order to dredge Estacio canal which connected the lake with the Mediterranean Sea. The intention was to allow boats of deeper draft to cross to the lagoon and the result was a great environmental impact due to the alteration of the temperature and salinity of the water, and therefore the ecosystems equilibrium. In 1979, one of the largest engineering works in Spain culminated: the Tajo-Segura transfer. The transfer of water from one river to another was made with the aim of converting the traditional dryland agriculture into irrigated, thus becoming this area in the so-called orchard of Europe although its strong rainfed nature.