## 4 Results
Figure 10: The localisation and depth analysis of potential non-drained urban basins in Wyszków City. Figure 9: Flooding threats in Wyszków City include risks from non-drained urban basins as well as overflow from riverbanks. Green areas occupy more than half of the city of Bielsko-Biala, with the green area resource index amounting to 53% (Figure 11a). Additionally, the percentage of biologically active index exceeds 60%. According to data from the Central Statistical Office for year 2021, the forested land area in Bielsko-Biala is 3179.9 netctares, translating to a forest cover of 24.9%, compared to the national average of 29.6%. In case of the Wyszkow City green areas occupy over 60% and account for nearly half of the city's area. The green area resource index for the city stands at 49.78% (Figure 12a). The percentage of biologically active index within the city (Figure 5) exceeds 68.15%. According to statistical data from 2021, the forested land area in Wyszkow totals 4938 hectares, corresponding to a forest cover of 29.5%, which is close to the national average of 29.6%. Based on a spectral (remote sensing) index that identifies green areas using satellite imagery (Sentinel-2) the Normalised Difference Vegetation Index (NDVI) was compared against anthropogenic areas of the city. This index includes all green spaces, encompassing both lush greenery and low-quality vegetation. The mapped visualization of the index provides information on the distribution of green areas within the anthropogenic zones of the city--areas where the majority of the population lives and works--as well as the fragmentation of individual green patches (Figures 11b and 12b). Furthermore, a comparison of green and anthropogenic areas offers quantitative insights into the availability of greenery in the urbanised parts of the city. In the Bielsko-Biala City, this index is around 79% while in the Wyszkow City, green areas within the urbanised areas identified through satellite imagery account for approximately 66%. An analysis of the distribution of green areas based on satellite data reveals a lack of vegetation in the northern parts of the city near service, industrial, and warehouse buildings. Figure 11: The map of green areas in Bielsko-Biala City consists of: (**a**) forests, shrubs, trees, and permanent crops based on the BDOT10K database, according to Equation (1); and (**b**) urban green areas derived from the NDVI index, according to Equation (2). After selecting the spatial units for evaluation, choosing the criteria, calculating the criterion values, and normalising them, the preliminary output of the multi-criteria analysis is a set of weights assigned to each criterion. For the city of Bielsko-Biala, the following criteria were available, with the corresponding weights assigned (Table 2). The first relevant product of the MCA analysis is a tabular ranking of districts based on the sums of standardised products of criterion values and criterion weights. This ranking can also be visualised to illustrate the vulnerability of districts to hydrological threats (Figure 13), where the deepest blue colour indicates that these districts are more prone to flooding, taking into account the criteria adapted from Table 2.  
As in the case of Bielsko-Biala City, appropriate criteria were selected for the city of Wyszkow (Table 3), to which the expert team assigned weight values.