The article presents issues related to modeling of the rainfall-runoff phenomenon. As factors influencing the simulation results, the velocity and direction of precipitation relative to the drainage basin were indicated. The possibility of underestimating the cross-sections of rainwater channels as a result of overlapping rain wave directions and the dominant flow direction in the rainwater channel network was pointed out. The research results to date indicate a reduction in the symptoms of this phenomenon as the complexity of the channel network increases. The final verification was based on the actual catchment. Calculations were made using the Epa SWMM 5.1.013 software. The results are presented in a graphic form to illustrate the variability of stormwater outflow.
The work presents issues of modelling water supply systems in the context of basic parameters characterizing their operation. In addition to typical parameters, such as water pressure and flow rate, assessing the age of the water is important, as a parameter of assessing the quality of the distributed medium. The analysis was based on two facilities, including one with a diverse spectrum of consumers, including residential housing and industry. The carried out simulations indicate the possibility of the occurrence of water quality degradation as a result of excessively long periods of storage in the water supply network. Also important is the influence of the irregularity of water use, especially in the case of supplying various kinds of consumers (in the analysed case - mining companies).
The verification of simulation model of combined sewage system was presented in article. The model of sewage system functioning in Głogów was developed using SWMM 5.1 (Storm Water Management Model) software. It was calibrated based on the results of field studies from the years 2011–13, while the properness of its activity was verified for the results of measurements carried out in 2014. The verification of the model showed acceptable discrepancies between the measured and simulated values of flow rates. Factors which caused differences were indicated and, on the basis of this, conclusions pertaining to further studies were formulated.
The article presents the current state of knowledge in the field of estimating preliminary values of storm water subcatchment calibration parameters in the case of using the Storm Water Management Model (SWMM) for building a model of storm water drainage system. The key issue is estimating the runoff width in the case of reducing the network structure and storm water catchments due to the shortening of calculation time and simplification of the model calibration process. Correction of one of the recommended literature methods has been proposed. The assessment was based on the real catchment model with single and multi-family housing. It was found possible to apply the proposed method in the case of reducing systems connected in series.
This paper presents the impact of rainfall on the degree of flood risk in the basin of the middle Bobr River in western Poland. When the average rainfall level reaches 15 to 20 mm, this apparently calm river may dramatically change its character within just one week. The most important flood risks are flood waves in the headwaters. Because of the mountain character of the river basin, during intensive rainfall there is a huge surface runoff and the water level rises rapidly in the river. This phenomenon was observed in June 2017 in the town of Zagan (Lubuskie Voivodeship).
It has been shown that the course and dynamics of hydrological processes occurring in the Bobr River basin depend on its physical and geographical characteristics and the influence of anthropogenic factors. The location is one of the main cause of numerous floods for Zagan, on the other hand changes in land development plays significant meaning in flood hazards. Continuous monitoring of the river is the basis for a comprehensive forecast of flood risks.
Water consumption is an amount characteristic to individual water sup-ply systems. It is described by values of the unitary consumption of water and unevenness coefficients. An analysis of consumption for the years 2009-2016 in two systems which are diverse in terms of the number of supplied recipients as well as the intended water use is presented. The values of unitary consumption indices as well as hourly and daily irregularity of consumption were calculated, and factors influencing the irregularity of consumption in different time frames indicated. Conclusions regarding the amount and irregularity of consumption were drawn and compared with guidelines and other analysed systems.
The work presents the results of the analysis of an existing water supply system. It contains a description of the analysed area in which the analysed system was located, as well as its parameters regarding water intakes and transport of water with pumps, the length and diameter of pipes, and a complication of the materials used to construct the network. Water demand accounting for the nature of the consumers using the water supply network was subject to analysis. The influence of changes in the distribution of water within a day for the basic categories of recipients was accounted for. The EPANET 2.0 program for the simulating water supply network operation, made available by the U.S. Environmental Protection Agency through a public-domain licence, was used to construct the model of the system. The obtained results of the simulation allowed for indicating the main problems with the use of the analysed system. Subject to analysis was the pressure pattern in characteristic nodes of the network from which mining companies, industrial plants and residential households were supplied. Usefulness of the developed simulation model in preparing the assessment of future modernization works was confirmed, allowing for the effects of their implementation to be assessed.