Alpine karst waters in Slovenia

Abstract

Some basic characteristics of the alpine karst waters in Slovenia are presented. By the method of hydrological balance it was estimated that their groundwater reserves can supply a spring with an average discharge 115 m3/s. According to the comparison between the extent of the alpine karst and the EIONET-SI data base on springs it was stated, that for approximately 1200 alpine karst springs the total capacity (not the average discharge, but the amount of water that can be captured at low waters) is around 15 m3/s. At present only some 25% of these reserves is exploited for the water supply of around 240.000 inhabitants. Due to high vulnerability and different human impacts the quality of these water resources is endangered. Therefore it is necessary to protect them with adequate measures planned on the basis of accurate hydrogeological data. Present level of protection is unsatisfactory, as the water protection decree was accepted only for one quarter of captured springs. Additionally, the expert basis for such decree was prepared for a little less than one fi fth of captured springs.

Predstavljene so osnovne značilnosti alpskih kraških voda v Sloveniji. Z metodo vodne bilance sem ocenila, da njihove zaloge zadoščajo za napajanje izvira s povprečnim pretokom 115 m3 /s. Po primerjavi obsega alpskega krasa s podatki o izvirih iz baze EIONET-SI je bilo ugotovljeno, da je skupna izdatnost (ne povprečni pretok, ampak količina vode, ki jo je možno zajemati ob nizkem vodostaju) približno 1200 alpskih kraških izvirov okrog 15 m3 /s. Za vodooskrbo je trenutno izkoriščenih le okrog 25 % teh zalog, z njimi pa se oskrbuje okrog 240.000 prebivalcev. Zaradi velike ranljivosti kraških vodonosnikov in različnih človekovih vplivov je ogrožena kakovost teh vodnih virov. Nujna je zato njihova ustrezna zaščita, ki pa mora temeljiti na kakovostnih hidrogeoloških podatkih. Trenutna stopnja zaščite je nezadovoljiva, saj ima le približno četrtina zajetih izvirov sprejet odlok o varovanju, še za nekaj manj kot petino pa so že pripravljene ustrezne strokovne podlage.