Quality of Croatian Inland Bathing Areas: Reference to The Region and EU

Abstract

Introduction: The Republic of Croatia (HR) has significantly invested in monitoring the quality of inland bathing areas during the past 10 years. The aim of this paper was to analyze the results obtained during the 2014-2019 period and to compare them with the Region (non-European Union [EU] countries neighboring Croatia) and EU. Moreover, bathing water quality data at two bathing areas of Zagreb (lakes Jarun and Bundek) were processed in more detail.Methods: The quality of inland bathing areas in the HR is monitored in five rivers and five lakes in nine Croatian counties; 19 of the 35 monitored sites are located in Zagreb County. Escherichia coli (EC) was determined by EN ISO 9308-3: 1998, while intestinal enterococci (ENT) were defined by EN ISO 7899-2: 2000. Statistical processing of the results was performed using the Microsoft Excel Statistical Package (Redmond, USA) and Statistica 13.5. (Stat.Sof.Inc., Tulsa, USA); the significance level was set to p < 0.05.Results: During the study period, the worst Croatian inland water quality was recorded in 2019 (excellent quality for only 25.9% of the bathing areas), while the best quality was recorded in 2015 (excellent quality in 57.1%). On average (2014-2019), the share of bathing areas with excellent quality in Croatia was 46.3% (i.e., under the EU average of 85.3%); with no poor locations (EU average was nearly 2%). A significant positive correlation was found between fecal indicators (EC&ENT) and the amount of precipitation, while a negative correlation with water and air temperature in lakes.Conclusions: The quality of Croatian inland bathing areas is significantly lower than the European average, while EU water quality is improving. Regarding the countries bordering Croatia, Italy, Slovenia, and Hungary have achieved better results, while Montenegro, Serbia, and Bosnia and Herzegovina are still in the process of developing the monitoring of the bathing water quality.

Inland and Coastal Bathing Water Quality in the Last Decade (2011–2020): Croatia vs. Region vs. EU

“…On the other hand, the Croatian share fluctuated significantly during the observed period (75% in 2011, 0% in 2012, 51.9% in 2018 and 14.6% in 2020) (Figure 3). The reason for this is that Croatian monitoring of inland waters is relatively new (since the 2011 season), so the number of sites has not yet stabilized [29]. During the ten-year study period, Germany had the highest proportion of excellent water quality (92.2%), while Spain had the highest proportion of poor water quality (11.6%), an average of 31 bathing sites per year.…”

“…On the other hand, the Croatian share fluctuated significantly during the observed period (75% in 2011, 0% in 2012, 51.9% in 2018 and 14.6% in 2020) (Figure 3). The reason for this is that Croatian monitoring of inland waters is relatively new (since the 2011 season), so the number of sites has not yet stabilized [29]. Looking at the EU as a whole, the first seven years of the monitoring period show a constant increase in the proportion of bathing sites with excellent water quality (70.4% in 2011, 82.1% in 2017) and a decrease of 4.6% in the last three years (80.8% in 2018, 79.1% in 2019 and 77.5% in 2020).…”