## 3 Results
### Hydrometeorological Conditions in the Catchment of the River Swierszcz
#### 3.2.2 Analysis of Selected Physical Indicators  
Table 4 compares the descriptive statistics of the physical parameters of rainwater with those of flowing water and groundwater. Figure 9 shows box plots of the physical test results for the analysed types of water. The water groups we tested showed statistically significant differences in turbidity (Kruskal-Wallis H = 12.60, \(p\) = 0.006). No significant differences in turbidity were found between the rainwater samples collected at points P1 and P2, but rainwater collected at point P2 and river water sampled from the Swierszcz P3 had significantly higher turbidity than water sampled from the deep wells. However, no differences in turbidity were found between rainwater collected at point P1 and the water from the deep wells (P4-P7) (Figure 9a). Groundwater was the only type for which the standard for acceptable levels of turbidity in drinking water was not exceeded [36]. In the case of the remaining water groups (rainwater and surface water), the turbidity values slightly exceeded the permissible  
Figure 8: Boxplots for microbiological parameters of the investigated water types. A comparison of the quality of rainwater (P1, P2), river water (P3) and water from deep wells (P4–P7) with drinking water standards. \({}^{\mathrm{a}\mathrm{b}}\) Distributions of results in groups not containing the same letter differed significantly at \(\alpha\) = 0.05 (Kruskal–Wallis test). Boxplots for: (**a**) total microbial counts at 36 \({}^{\circ}\)C, (**b**) total microbial counts at 22 \({}^{\circ}\)C, (**c**) coliform bacteria, (**d**) _Escherichia coli_, (**e**) intestinal enterococci, (**f**) _Pseudomonas aeruginosa_. limit for drinking water. Compliance with drinking water standards for rainwater was 20% and 60% for P1 and P2, respectively. There were no significant differences in the colour between rainwater collected at points P1 and P2 and water from the deep wells (P4-P7). By contrast, water from the River Swierszcz had a significantly higher colour value (Kruskal-Wallis H = 22.19, \(p<0.001\)) (Figure 9b), which considerably exceeded the limit for drinking water (P1 and P2) and water from the deep wells (P4-P7) met the guidelines for drinking water. The colour standard for drinking water was exceeded only once at P2 \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline
**Point** & **Valid N** & **Mean** & **Median** & **Min** & **Max** & **Std. Dev.** & **Coef. Var.** &
\begin{tabular}{c} **Var.** \\ **Group** \\ \end{tabular} & **Compliance * (\%)** \\ \hline \multicolumn{10}{c}{Turbidity (NTU)} \\ P1 & 10 & 1.54 & 1.36 & 0.8 & 2.7 & 0.62 & 40.1 & High & 20 \\ P2 & 10 & 2.82 & 1.95 & 0.2 & 6.7 & 2.37 & 84.1 & High & 20 \\ P3 & 10 & 3.24 & 2.25 & 1.7 & 10.4 & 2.66 & 82.0 & High & 0 \\ P4–P7 & 4 & 0.38 & 0.25 & 0.08 & 0.93 & 0.39 & 103.1 & Very high & 100 \\ \multicolumn{10}{c}{Colour (mg/ L Pt)} \\ P1 & 10 & 4.59 & 3.40 & 0.97 & 10 & 3.27 & 71.3 & High & 100 \\ P2 & 10 & 6.58 & 3.04 & 0.59 & 29 & 8.42 & 127.9 & Very high & 90 \\ P3 & 10 & 60.7 & 52.5 & 32 & 109 & 27.05 & 44.6 & High & 0 \\ P4–P7 & 4 & 1.60 & 1.74 & 0.1 & 2.83 & 1.19 & 74.4 & High & 100 \\ \multicolumn{10}{c}{Specific conductance at 25 \({}^{\circ}\)C (uS/ cm)} \\ P1 & 10 & 40.256 & 30.85 & 16.21 & 84.64 & 22.85 & 56.8 & High & 100 \\ P2 & 10 & 16.60 & 13.43 & 6.92 & 37.32 & 10.08 & 60.7 & High & 100 \\ P3 & 10 & 238.3 & 246.5 & 186 & 272 & 27.62 & 11.6 & Low & 100 \\ P4–P7 & 4 & 384.5 & 392.5 & 310 & 443 & 59.17 & 15.4 & Low & 100 \\ \hline \hline \end{tabular}  
* Compliance with the drinking water standard.  
\end{table} 
Table 4: Descriptive statistics of the physical parameters of rainwater versus flowing water and groundwater. Figure 9: Boxplots of the physical parameters of the tested water groups. Comparison of the quality of rainwater (P1, P2), river water (P3) and water from the deep wells (P4–P7) with drinking water standards. abc Distributions of results in groups not containing the same letter differed significantly at \(\alpha=0.05\) (Kruskal–Wallis test).