The paper discusses the water resources of the Krężniczanka River catchment. The catchment with an area of 224.9 km2 is located south-west of Lublin. The characteristics of the groundwaters and runoff were determined based on hydrological and hydrogeological materials of the Department of Hydrology of the Maria Curie-Skłodowska University (UMCS). Mean runoff in the period from 2010 to 2016 amounted to 125.7 mm, precipitation 629.4 mm, and evapotranspi-ration 503.7 mm. A strong relationship was determined between the rhythm of runoff and ground-water level fluctuations. The contribution of groundwater supply in total runoff equalled 81.5%.
This study presents the results of tests conducted in 2009 and 2010 on experimental sites installed on the roof of the Science and Education Building of the Wroclaw University of Environmental and Life Sciences. The aim of the analysis was to determine the retention capacity of green roofs and the runoff delays and peak runoff reduction during rainfall recorded in Wroclaw conditions. The research shows that green roofs allow to reduce the volume of runoff stormwater in comparison to conventional roofs, that they delay the runoff in time and influence the reduction of the maximum runoff intensity, and thus may limit the impact of stormwater on the stormwater drainage and combined sewage systems.
Runoff estimation is a key component in various hydrological considerations. Estimation of storm runoff is especially important for the effective design of hydraulic and road structures, for the ﬂood ﬂow management, as well as for the analysis of land use changes, i.e. urbanization or low impact development of urban areas. The curve number (CN) method, developed by Soil Conservation Service (SCS) of the U.S. Department of Agriculture for predicting the ﬂood runoff depth from ungauged catchments, has been in continuous use for ca. 60 years. This method has not been extensively tested in Poland, especially in small urban catchments, because of lack of data. In this study, 39 rainfall-runoff events, collected during four years (2009–2012) in a small (A=28.7 km2), urban catchment of Służew Creek in southwest part of Warsaw were used, with the aim of determining the CNs and to check its applicability to ungauged urban areas. The parameters CN, estimated empirically, vary from 65.1 to 95.0, decreasing with rainfall size and, when sorted rainfall and runoff separately, reaching the value from 67 to 74 for large rainfall events.
In the paper, the research results on the removal of aliphatic hydrocarbons (C7 to C30) on constructed wetlands have been presented. The research has been realized on the semi-technical scale constructed wetlands. planted with reed Phragmites australis. The experimental installation is located on the filling station in Balice and treats the fraction of stormwater from this utility. The concentrations of total aliphatic hydrocarbons in analyzed stormwater were between 96.02 µg/dm3 and 6177.33 µg/dm3 , and from 47.55 µg/dm3 to 5011.14 µg/dm3 in effluent from the installation. The average total aliphatic hydrocarbons removal effectiveness was 48%, the values ranged from 19% to 81%. Hydrocarbons C14 to C18 were removed with the lowest effectiveness (26%–32%), the lighter hydrocarbons – with higher one (39%–68%), however the highest removal effectiveness were observed for the hydrocarbons with the highest carbon atoms numbers (from 51% for C20 to 92%–93% for C26–C30).