Cerknica/Kupa Αquifer - 96

Croatia - Slovenia

Aquifer type 2

In Slovenia: Surface water and groundwater divides separate from state border, recharge in one country, discharge in adjacent.

The Cerknica/Kupa Αquifer is made up of Mesozoic/Triassic and Cretaceous limestones and dolomites with some alluvium in the river valley; it is unconfined.

Groundwater flows from Croatia to Slovenia and Slovenia to Croatia. There are weak to medium links with surface waters systems.

Cerknica/Kupa ΑquiferCroatia
Slovenia
Area (sq. km) 137 238
Groundwater uses and functions Drinking water supply; supports ecosystems. Local drinking water supply.
Pressure factors None, very scattered population; occasional
bacteriological pollution the only reported problem.
None, sparsely populated, forested with some
extensive agriculture and pasture.
Groundwater management measures Existing protection zones. None
Trends and future prospects Border length 32 km. No transboundary impact. Delineation
of transboundary groundwater is needed (through common
research), and development of monitoring programmes.
Border length 32 km. Population ~10 635 (45 inhabitants/
km2). No transboundary impact. Not at risk. Good
chemical status. It is unclear which groundwater
systems in the two countries correspond to each other;
delineation of transboundary groundwater needs
common research and a bilateral decision to propose
a transboundary groundwater, if appropriate.
Other information Transboundary aquifer under consideration, but not approved. In the basin of the Kolpa/Kupa River, within that of the Sava River.