Stormwater Management in the City of Warsaw: A Review and Evaluation of Technical Solutions and Strategies to Improve the Capacity of the Combined Sewer System

Abstract

Urban flooding is an increasingly common phenomenon around the world. The reasons are usually attributed to the insufficient capacity of the combined sewer system and its inability to adapt to the changing dynamics of rainfall. This is also the case in Warsaw (the capital of Poland), where the sewage system was designed in the 1960s. The aim of the article is to highlight possible hydrological solutions that would significantly improve Warsaw’s situation in terms of rainfall runoff. The article looks at some solutions that were previously mentioned in the literature and presents an assessment of the possible changes in land use/land cover on the hydrological processes and improvements in the general hydrological situation of Warsaw. In addition, the article points out the need to update the programme and spatial approach to the discharge of water from specific watersheds in Warsaw, as well as to establish a single manager for stormwater drainage in the city of Warsaw. An important issue is the restoration of natural retention basins in the city and the construction of artificial basins in places with frequent local flooding. The article emphasises the importance of building individual detention basins (as well as low-impact developments) for newly planned investments. Other important aspects are as follows: the construction of suitable underground or open channels, the need to disconnect Ursynów’s stormwater runoff from the catchment area of the Służewiecki Stream and to channel it along the southern bypass for Warsaw (S-2) to the dry lakes and ponds in Wilanów. Finally, the article discusses the application of Sustainable Drainage Systems (SuDS) and Real-Time Control (RTC) in urban drainage systems as a possible solution to improve wastewater management in urban areas.

Evaluation of the Influence of Catchment Parameters on the Required Size of a Stormwater Infiltration Facility

“…The relations that were obtained for the model catchments were confirmed even with extreme rainfall, which had a probability of p = 0.00098. Considering that many regions of the world are experiencing an increase in extreme rainfall events [75,76], this finding is particularly significant and confirms that the results of the analysis can be applied not only to Poland, but also to other regions of the world.…”

A Comparison of Different Machine Learning Algorithms in the Classification of Impervious Surfaces: Case Study of the Housing Estate Fort Bema in Warsaw (Poland)

“…Mapping and monitoring of impervious surfaces is required for a number of purposes, e.g., urban planning [1], monitoring subtle urban changes (so-called subtle urban dynamics) [2][3][4], as an essential component of effective stormwater management [5], to assess the hydrologic condition of an area/catchment [5], to evaluate water quality [5][6][7], but also to facilitate rational stormwater management policies for specific lands/properties [8], to improve environmental management and finally to promote sustainable urban development, including construction of appropriate facilities/infrastructure [1]. Other important applications of impervious surface mapping/classification include developing appropriate standards for managing pollution from stormwater runoff [9], implementing flood control measures [5,8] and supporting emergency management activities [5]. Sobieraj et al [5] emphasize the need to map impervious surfaces in the context of so-called sustainable drainage technologies and small-scale architecture (sustainable urban drainage systems /SUDS/, water-sensitive urban design /WSUD/, low impact developments /LID/).…”

“…Other important applications of impervious surface mapping/classification include developing appropriate standards for managing pollution from stormwater runoff [9], implementing flood control measures [5,8] and supporting emergency management activities [5]. Sobieraj et al [5] emphasize the need to map impervious surfaces in the context of so-called sustainable drainage technologies and small-scale architecture (sustainable urban drainage systems /SUDS/, water-sensitive urban design /WSUD/, low impact developments /LID/). According to Bauer et al [10], a measure of imperviousness can also be used as a proxy for assessing environmental quality.…”

“…More specifically, impervious surface is an indicator of the ecological health of the areas in question [9]. It indicates the degree of urbanization and has a direct impact on water balance [9] and temperature cycles [5] as well as water quality [5][6][7][8]11,12]. In this context, it is worth noting that the need for detailed estimates of impervious surfaces has increased [1,5,7,8].…”

“…It indicates the degree of urbanization and has a direct impact on water balance [9] and temperature cycles [5] as well as water quality [5][6][7][8]11,12]. In this context, it is worth noting that the need for detailed estimates of impervious surfaces has increased [1,5,7,8]. Yang et al [13] state that accurate and upto-date geospatial data on urban impervious surfaces serve a multi-level study of urban ecosystems.…”