Low Impact Development Modeling to Manage Urban Stormwater Runoff: Case Study of Gorzów Wielkopolsk

Abstract

Uncontrolled urbanization causes local flooding and deterioration of the water quality of receivers as a result of an increase in peak flow rate and increased washing out of contaminants from the catchment area. Currently, classic storage tanks are most often used. An alternative solution may be the use of Low Impact Development (LID), i.e. the preservation and restoration of natural landscape elements, minimizing the imperviousness of the catchment in the form of rain barrels, permeable walkways or bio-retention reservoirs. The comparison of both techniques was carried out using the Environmental Protection Agency Storm Water Management Model (EPA SWMM). The influence of several solutions on a selected urbanized catchment located in Gorzów Wielkopolski was tested.

Runoff Volume Reduction Using Green Infrastructure

“…This is probably due to the fact that some of the water remaining after a flooding event in the catchment area in the depressions of the terrain. The values obtained for rain gardens are also similar to the examples of using only rain harvesting [40].…”

“…The receiver of stormwater is the Srebrna stream (Figure 4), a tributary of the Kłodawka river, which flows into the Warta river, Poland's second-longest river within its borders after the Vistula and third-longest in total length. The calculation sample was carried out using a calibrated simulation model of a chosen subsystem of draining rainwater connected with a separated rainwater catchment [40]. The model was prepared in 2016 and calibrated by a commercial company using measurement data obtained during a measurement campaign carried out in 2016 and 2017.…”

“…Variants accounting for storage cover the following implementations, which are present at the stage of realization [40]:  reinforced concrete, underground retention chamber with an active capacity of 320 m 3 ;  an underground reinforced concrete tank with an active capacity of 460 m 3 , including a tank with a capacity of 100 m 3 for pre-treated sewage with an uptake point for water for municipal purposes;  modernization of existing open retention tank, with an active capacity of 3640 m 3 , including 100 m 3 of the tank for pre-treated sewage with an uptake point for water for municipal purposes;  constructing a by-pass eliminating the influence of too densely located wells in Szarych Szeregów Street;  reconstruction of conduits situated with a negative slope.…”

“…In addition, also planned is the use of field measurements realized prior to and after implementing the pilot program of at-home rain gardens, infiltration trenches and rain barrels, making use of actual rainfall data measured in the catchment [60]. As already mentioned, the problem of local flooding as a result of excessive sealing of urban catchments is not a local problem, but concerns cities in countries almost all over the world [40,42]. Ironically, such problems affect not only densely built-up areas [42], but also typical suburban areas with relatively low-density housing [40].…”

“…As already mentioned, the problem of local flooding as a result of excessive sealing of urban catchments is not a local problem, but concerns cities in countries almost all over the world [40,42]. Ironically, such problems affect not only densely built-up areas [42], but also typical suburban areas with relatively low-density housing [40]. The widespread rainwater management, e.g., through the use of LID, is observed in many countries [9,47], but it is not everywhere accepted or recommended as it is in countries that do well in this field.…”