No abstract

Good quality water supplies and safe sanitation in urban areas are a big challenge for governments throughout the world. Providing adequate water quality is a basic requirement for our lives. The colony forming units of the bacterium Legionella pneumophila in potable water represent a big problem which cannot be overlooked for health protection reasons. We analysed several methods to program a virtual hot water tank with AI (artificial intelligence) tools including neuro-fuzzy systems as a precaution against legionelosis. The main goal of this paper is to present research which simulates the temperature profile in the water tank. This research presents a tool for a water management system to simulate conditions which are able to prevent legionelosis outbreaks in a water system. The challenge is to create a virtual water tank simulator including the water environment which can simulate a situation which is common in building water distribution systems. The key feature of the presented system is its adaptation to any hot water tank. While respecting the basic parameters of hot water, a water supplier and building maintainer are required to ensure the predefined quality and water temperature at each sampling site and avoid the growth of Legionella. The presented system is one small contribution how to overcome a situation when legionelosis could find good conditions to spread and jeopardize human lives.

Abstract. Grey water contributes significantly to waste water parameters such as biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total phosphorus (Ptotal), total nitrogen (Ntotal), ammonium, boron, metals, salts, surfactants, synthetic chemicals, oils and greases, xenobiotic substances and microorganisms. Concentration of these pollutants and the water quality highlights the importance of treatment process in grey water systems. Treatment technologies operating under low energy and maintenance are usually preferred, since they are more cost effective for users. Treatment technologies based on natural processes represent an example of such technology including vegetated wall. Main aim of this paper is to introduce the proposal of vegetated wall managing grey water and brief characteristic of proposed system. Is expected that prepared experiment will establish the purifying ability and the potential of green wall application as an efficient treatment technology.

A serious problem in recent years of waterworks praxis has appeared to be the one with growing necessity for surface water detention . Continuous growth of natural terrain coverage for building construction, industry, free time activities and transport reasons leads to a widening of the area of build surface and lack of natural terrain with a capability of natural rainfall water infiltration. This causes serious damage to the natural water cycle. In cases where rainfall water falls on natural terrain, most water soaks in the soil and becomes part of the subsoil water. Only about 20% of rainfall water comes to rivers or is carried to stormwater drainage. As a consequence of the continuous growth of building construction and urban development, the natural terrain is replaced by compact soil; for example, the roofs of industrial, residential, commercial or other buildings, road networks, car parks etc. When the rainfall water reaches these surfaces almost 80% of this water flows to the waste-water disposal system or rivers and only 20% soaks into the soil. This leads to ecological damage as floods, torrential rain, and the decline of subsoil water level, local soil dehydration and endangering of sensitive ecosystems. It is necessary to build and develop not only urban constructions but also the artificial regulation of water circulation in nature, which contribute to the maintenance of ecological stability of the chosen location.

Water consumption in residential parts of urban areas is just one part of the water management problems. Contemporary potable water management is not sustainable whereas we use potable water for flushing toilets, irrigation or washing vehicles. The appropriate solution is to substitute potable water with rainwater for some purposes and this water source is considered sustainable. Submitted paper presents risk assessment using risk analysis of the rainwater harvesting (RWH) system. This paper does not deal with the system in details but informs about the selected approach of the evaluation methodology verified by analytical hierarchy process.