A team from the Hellenic Survey of Geology and Mineral Exploration (H.S.G.M.E.) carried out a visit to the island of Megisti (Kastellorizo), the southeasternmost point of Greece, as part of the project “Groundwater Monitoring Network” (DIPYN).
During the visit to Megisti, groundwater level measurements were taken at two observation wells designated for monitoring. Water samples were collected, and physicochemical analyses were performed on-site using portable instruments. The geologist Konstantina Tsoulou also met with the Mayor, Mr. Giorgos Sampsakos, to discuss the current state of the island’s groundwater resources.
Monitoring points (wells) in the settlement of Kastellorizo.
The briefing focused on the characteristics of Megisti’s groundwater system, which is of limited hydrogeological interest and mainly found within carbonate and alluvial formations. Almost the entire island consists of karstified and highly fractured limestones, which are directly connected hydraulically with the sea, leading to seawater intrusion.
The few boreholes drilled on the island were deemed non-viable due to salinization. However, in the settlement of Kastellorizo, lateral deposits host a small and shallow aquifer where several wells have been drilled, though most are no longer in use. The island’s domestic and small-scale irrigation needs are currently met through a desalination unit.
The Church of Agios Merkourios with its rainwater collection cistern.
The main objective of the DIPYN project is the systematic monitoring and assessment of the quantitative and qualitative status of Greece’s major groundwater systems across 14 Water Districts, ensuring compliance with Directives 2000/60/EC, 2006/118/EC, and 91/676/EEC. The ultimate goal is to protect groundwater resources through targeted interventions aimed at halting or reversing water quality degradation. The project involves extensive fieldwork for collecting hydrological, hydrogeological, hydrochemical, and physicochemical data, which are subsequently processed and evaluated.
Panoramic view of Megisti.
Top photo: Meeting between the H.S.G.M.E. team (Ms. K. Tsoulou) and Mayor G. Sampsakos.