## 4 Results and Discussion
To assess the quality of DMR 3.5 we entered 516 points from a detailed planimetric and hypsometric survey. Subsequently 23 exclusion points were identified, which characterized the bridge structures in the locality. The calculation was carried out using a set of 493 points, of which 129 points represented slope edge, 241 points characterized slope foot and 123 water. The set of geodetic measurements included control measurements, and a set of points was created within the DMR 3.5 product with data regarding the factor of height. The basis of assessment consisted of evaluation of height differences between both products (\(z_{DMRI}-z_{Si}\)). Vertical accuracy of the model may be checked at every single instance of the measured set points (Table 3). The declared accuracy of DMR 3.5 is assumed to be \(\pm\)2.50 m, which demonstrates a certainty interval of 90%. The results obtained comply with the standards of accuracy set out by the Geodesy, Cartography, and Cadastre Authority of Slovak Republic, but for the process of hydrodynamic modeling DMR 3.5 is inappropriate with respect to its accuracy and also for its grid size, which does not permit detailed terrain presentation. This conclusion is also confirmed by the control measurement of points using the RTK method. The problematic aspect of DMR 3.5 is its process of generation based on background contour lines at scales of M 1:10,000 and M 1:25,000. A major disadvantage is that DMR 3.5 does not define the shape of the bottom of the watercourse. The shape of the bottom and the size of the cross-section of the water environment is a necessary input to the hydrodynamic model. Its absence in hydrodynamic modeling results in incorrect interpretation of the extent of the inundation area and the depth of the modeled flood. Comparison of DMR 3.5 and RTK measurements: maximum levels of high difference values arise surprisingly almost at the slope edge (+2.3 m), minimum levels of height difference values are \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline  & \(d_{z}\) & \(\partial_{z}\) & \(\dot{\mu}_{z}\) & \multicolumn{5}{c}{**Certainty Interval**} \\ \cline{4-9}  & **[m]** & **[m]** & **[m]** & **50\%** & **68.3\%** & **90\%** & **95\%** & **99.8\%** \\ \hline All & 1.36 & 1.48 & \(-\)0.78 & 1.00 & 1.48 & 2.43 & 2.90 & 4.44 \\ Slope edge & 2.27 & 1.14 & \(-\)2.23 & 0.77 & 1.14 & 1.87 & 2.23 & 3.42 \\ Slope foot & 1.11 & 1.08 & \(-\)0.80 & 0.73 & 1.08 & 1.77 & 2.11 & 3.23 \\ Water & 0.87 & 0.79 & 0.77 & 0.53 & 0.79 & 1.30 & 1.55 & 2.37 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Absolute vertical error of DMR 3.5 calculated by Equations (2)–(4), Section 2.2.  
predominantly on the watercourse (\(-0.1\) m). Like [67], we agree that a combination of several types of spatial data is needed to define the topography of a watercourse. This is not always the case since there are significant differences in height in the watercourse (between DMR 3.5 and terrain from RTK measurement) (Figure 12). This (DMR 3.5) is therefore not suitable for hydrodynamic modeling of flood scenarios. These lacks in terrain models are confirmed by the work of [PERSON] [50]. Next Table 4 presents an evaluation of the individual quality components of spatial data produced by means of DMR available for the territory of the Slovak Republic, supplemented with local geodetic measurements The assessment also takes into account the production of DMR 5.0, already covering a substantial part of the Slovak Republic (not included east part of Slovakia) and with the expectation of creating the final version by 2022.