There are 66 aquifers of local and national importance in Cyprus. The great majority of them are phreatic aquifers developed in river or coastal alluvial deposits. These form the largest and the most dynamic aquifers replenished mainly by river flows and rainfall. There are three large coastal aquifers which include the beds of all rivers discharging into the sea. The coastal parts of these aquifers consist of sands, silts, limestones, conglomerates and clays. The riverbeds consist of alluvial deposits, gravels, sands and silts. These aquifers are phreatic roughly 30 m deep. With the exception of the large but not very productive aquifer developed in the Troodos Range igneous rocks all other aquifers exist in gypsum, sandstones, limestones and chalks. These are mainly phreatic. In some cases, parts of these aquifers are semi-confined and/or confined covered by silty-clayey layers and/or marls and sandy marls. The Troodos Range aquifer has developed in low permeability ophiolites and in fractured zones of igneous rocks of medium permeability causing it to be confined in parts.

It should be noted that the River Basin Management Plans of Cyprus {(Article 13 of the Water Framework Directive, 2000/60/EC (WFD)} are developed for “Groundwater Bodies”, which comprise groups of aquifers of similar conditions i.e. similar hudrogeological/hydraulic characteristics, type, quantitative and qualitative status, pressures and uses. Article 5 of WFD requires that these conditions are reassessed every 6 years based on the results of the groundwater monitoring programs of the previous 6 years and any additional information acquired during the same period and the “Groundwater Bodies” are redefined (re-characterised) and revised (regrouped) accordingly.

As part of the preparative work for the elaboration of 1st River Basin Management Plan of Cyprus, which concerned the implementation of WFD for the period from the Directive’s date of entry into force until 2015 (1st WFD implementation cycle), the 66 aquifers were grouped into 20 “Groundwater Bodies”. During the 2nd WFD implementation cycle the “Groundwater Bodies” were revised to 22 and during the 3rd implementation cycle of WFD to 23.