The aim of this study was an assessment of feasibility of conversion of sewage holding (SH) tanks to rainwater harvesting (RWH) tanks in Poland. Such a conversion may partly solve the problem of water scarcity for irrigation of plants in individual small gardens and reduce tap water consumption. Seven methods of RWH tanks sizing were applied to an example of a small harvesting system of the roof area equal to the garden irrigation area of 100 m2 for three different irrigation doses. A new criterion was introduced to optimize the tank capacity. Economic optimization was provided for new RWH tanks and for the tanks adapted from abandoned SH tanks. Results obtained for a system sited in west-central Poland in an average year have shown that design capacity of RWH tanks varied markedly between sizing methods. The conversion of SH tanks to RWH tanks is profitable, especially for irrigation due to scarcity of water in relatively dry west-central regions. Conversion of individual SH tanks in a good technical state to RWH tanks is relatively simple and cheap. The potential increase in storage volume due to the conversion of individual SH tanks to RWH tanks could reach all over Poland 215–350 dam3 per year, and individually can save up to 18–25% of total annual water use.
The paper aims to answer the following questions: What are the trends in streetscape design? And how can streetscape become more resilient to climate change in the coming years? Although the research questions of exploratory nature also challenge theoretical claims, this is a hypothetical study, designed to foster a discussion about the visions of the future streetscape and new technology for an urban sidewalk. It covers a description and a cross-case comparison of an experimental product – the Climate Tile, implemented in Denmark in 2018, and a theoretical solution – the Sponge Pavement – a model system based on the structural soil foundation and permeable surface, evolved as an idea in 2018 in Poland. The cases are examples of innovations selected to describe a new type of water-permeable surfaces matching the urban context. Both solutions share common features: they are in that there is no need to place heavy equipment on the project site; they match the urban context of a dense city, being smooth, resistant and easy to clean. The comparison of the Climate Tile and the Sponge Pavement allowed determining the optimal application for the given solution. It also proved the trend towards the rainwater management-oriented direction of the development of the streetscape of the future. The study results could contribute to the discussion of the streetscape of the future. We would like to focus on the idea of the Sponge Pavement for further development in laboratory tests and as the pilot project.
Scarcity of freshwater is one of the major issues which hinders nourishment in large portion of the countries like Ethio-pia. The communities in the Dawe River watershed are facing acute water shortage where water harvesting is vital means of survival. The purpose of this study was to identify optimal water harvesting areas by considering socioeconomic and biophysical factors. This was performed through the integration of soil and water assessment tool (SWAT) model, remote sensing (RS) and Geographic Information System (GIS) technique based on multi-criteria evaluation (MCE). The parame-ters used for the selection of optimal sites for rainwater harvesting were surface runoff, soil texture, land use land cover, slope gradient and stakeholders’ priority. Rainfall data was acquired from the neighbouring weather stations while infor-mation about the soil was attained from laboratory analysis using pipette method. Runoff depth was estimated using SWAT model. The statistical performance of the model in estimating the runoff was revealed with coefficient of determination (R2) of 0.81 and Nash–Sutcliffe Efficiency (NSE) of 0.76 for monthly calibration and R2 of 0.79 and NSE of 0.72 for monthly validation periods. The result implied that there's adequate runoff water to be conserved. Combination of hydrological model with GIS and RS was found to be a vital tool in estimating rainfall runoff and mapping suitable water harvest home sites.