Page 3 - Grillini2015

Research &
development

A hydrological and geochemical
survey of the groundwater resource
of Favignana Island

Small islands suffer water shortage, and tourist pressure makes it even worse: Favignana island is the site that best
represents such conditions, due to the contrast between the intense anthropization and the harsh nature
of the terrains. The ENEA study hypothesized a solution in identifying the best areas where groundwater is abundant
and presents the best conditions to take water samples for anthropic use. With hydrological measurements
and chemical analyses, an area theoretically interesting has been identified in the eastern sector, where groundwater
is better in quality and just a few meters deep below the ground. Westwards, instead, it is at a lower depth
and saltier, due to its more intense contamination with seawater. Yet the amount of available groundwater
is everywhere so poor that more intense water sampling is not recommended: people have always been living
in good balance with nature, and they know how to manage the island’s groundwater resource, fed by rare
precipitations, as a supplement to the drinking water supply coming from Trapani

DOI 10.12910/EAI2015-067

n M. Grillini, M. De Cassan, M. Proposito

Introduction

The small islands scattered over the Italian seas have basin-shaped roofs of their houses downward into
always had to cope with a shortage of water resources, underground cisterns [3]. Actually, agriculture has been
because of the harsh nature of insular grounds and affected too, compelling farmers to breed drought-
the scanty areal extent of the islands themselves [1]: resistant and brackish-water-tolerating cultivars [4, 5].
moreover, their aquifers are usually very thin, and the Nowadays, the growing tourist pressure [6, 7] is
water in the wells is scarce and often brackish; in fact, worsening the problem,particularly during the summer:
often low quality is added to the natural scarcity of if, on the one hand, it is an income source for islanders,
water resources, due to the seepage of salty water from on the other it demands larger amounts of freshwater,
the surrounding sea [2]. indispensable for restaurants and hotels [8-12].
Islanders have therefore learned, over the centuries, With high summer temperatures, and scarce seasonal
to manage their water resources in extremely thrifty rains,the islands of the Egadi archipelago,off the western
ways, developing peculiar techniques to collect and end of Sicily, in sight of the town of Trapani, are among
preserve the rainwater, such as conveying it from the the most sensitive ones to this serious inconvenience:
that is why they represent the ideal subject of a study
Contact person: Marcello Grillini aimed at dealing with the problem [13-16].
marcello.grillini@enea.it Actually, the present ENEA study fits in the activities
targeted at a more sustainable touristic offer [17,18]: in
detail, the starting purpose was to detect possible areas
where groundwater is of the best quality, and where it

20 EAI Energia, Ambiente e Innovazione 4/2015