Safety of drinking water in Gorski Kotar – five-year period 2011 – 2015

Cilj: Osiguranje zdravstveno ispravne vode osnovna je potreba svakog čovjeka. S obzirom na dugogodišnje mikrobiološko onečišćenje u vodoopskrbnoj mreži Gorskog kotara, analizirano je petogodišnje razdoblje. Cilj ovog rada bio je pratiti utjecaj promjena zakonske regulative i sanitarno-tehničkih uvjeta – ugradnje većeg broja automatskih klorinatora na broj ispitanih uzoraka iz vodoopskrbnog sustava, kao i na rezultate ispitivanja parametara zdravstvene ispravnosti vode za ljudsku potrošnju. U radu je uspoređen profil onečišćenja vode za ljudsku potrošnju u Gorskom kotaru i ostalim dijelovima županije. Metode: Statistički su obrađeni i interpretirani rezultati županijskog monitoringa zdravstvene ispravnosti vode za ljudsku potrošnju na području Gorskog kotara u razdoblju od 2011. do 2015. (broj ispitanih uzoraka N = 7.047). Rezultati: Stupanjem na snagu Pravilnika o parametrima sukladnosti i metodama analize vode za ljudsku potrošnju (NN 125/13, 141/13 i 128/15) broj uzoraka na temelju kojih se prati stanje vode u razvodnoj mreži Gorskog kotara je šesterostruko smanjen, ali je broj ispitanih pokazatelja povećan. Ugradnja automatskih klorinatora (2012. g. i 2013. g.) rezultirala je dvostrukim smanjenjem broja nesukladnih uzoraka. Zaključci: Primjena Pravilnika (NN 125/13, 141/13 i 128/15) rezultirala je značajnim smanjenjem broja analiziranih uzoraka u pojedinim vodoopskrbnim sustavima, što je procjenu njihovog stanja uvelike otežalo. Ugradnjom automatskih klorinatora broj nesukladnih uzoraka u Gorskom kotaru upola je smanjen. Glavni razlog zdravstvene neispravnosti vode za ljudsku potrošnju u vodovodima Gorskog kotara je fekalno onečišćenje vode, dok u ostalim dijelovima županije najčešće od zadanih kriterija odstupaju mutnoća vode, povećani broj kolonija (UBB) i nusprodukti klorinacije.
Aim: Ensuring the safety of potable water is a necessity of every human being. Taking into account long-term microbiological contamination of water supply network of Gorski Kotar, the results of 5-year County monitoring program of potable water safety in that region have been analysed. The aim of this study was to monitor the impact of amendment of legal standards as well as sanitary and technical requirements – the insertion of higher number of chlorinators on the number of examined samples deriving from the water supply system as well as the influence on the results of testing of the health parameters of water intended for human consumption. This study compared the contamination profile of water for human consumption in Gorski Kotar and other regions of the Primorje-Gorski Kotar County. Methods: This study presents the elaborated and interpreted results of the County monitoring program of potable water safety in the region of Gorski Kotar during the 5-year period (2011–2015; the number examined samples N = 7,047). Results: Application of the Regulations on the parameters of assessment and methods for the analysis of water for human consumption (Official Gazette 125/2013, 141/2013/, 128/2015) provides six times lesser number of samples for the monitoring of water supply system network in Gorski Kotar, but the number of analysed parameters was increased. Installation of automatic chlorinators (2012 and 2013) resulted with twice smaller number of non-compliant samples of drinking water. Conclusions: Application of the the Regulations (Official Gazette 125/2013, 141/2013, 128/2015) resulted with the significant reduction of samples for certain water supply systems making the objective assessment of their condition much harder. The installation of automatic chlorinators reduced the number of non-compliant water samples in Gorski Kotar by half. The main reason for non-complying samples of water for human consumption in the water supply systems of Gorski Kotar is faecal contamination, while for the other parts of the County major deviation from stipulated criteria are turbidity, increased number of colonies (Heterotrophic Plate Count – HPC) and chlorination by-products.