The ever-recurring high levels of the river Danube have forced Bratislava to be protected from floods. In the western part of the city, it was necessary to ensure the sealing of the heterogeneous fills located just on the banks of the Danube. The performed sealing works did not take into account the actual properties of the subsoil. The first part of the paper deals with the factual situation at the site and the shortcomings of subsoil injection.

Thermal baths in Slovakia are producers of wastewater, which have considerable enegry potential. Wastewater often exceeds the maximum temperature that can be discharged to the recipient without harming the environment. In many cases, this requirement is not met, and swimming pool operators must face sanctions for environmental pollution. The aim of the paper is to present the possibilities of using the energy potential of wastewater, which would ensure its required temperature.

The current way in drainage of roads is the concentration of rainwater in the subsoil of roads, so that rainwater does not drain into the sewer system, but freely infiltrates into the subsoil. The aim of this research is to optimize the structural layers of green parking lots with AS-TTE grassing blocks. During the design of structural layers and new types of materials, will be optimized to allow maximum water infiltration into the subsoil and at the same time keep the requirements for load-bearing capacity of structural layers according to ČSN 72 1006. Laboratory tests will be performed focusing on basic physical and mechanical properties, water permeability and adsorption of oil drips.

This paper introduces the results of the project „Tools for effective and safe management of rainwater in Prague city – RainPRAGUE”. Achieved results show the options for higher living standards for inhabitants in urbanised area of Prague city regarding to current and expected trends in climatic change. The project consists of three concepts. The concept 1 was focused on effective management of rainwaters in the urban area of Prague vicinity. Concept 2 was focused on WEB-GIS-based software that will be used to manage emergency hydrological situations on watercourses within the area of Prague city. It will help to prevent and protect the resident population, property and the environment against negative impacts of flash floods. Concept 3 was aimed to develop of WEB-GIS-based software that can assist in delineation of areas with heightened risk of surface runoff, erosion and sediment/pollutant as well as undue drainage runoff. The WEB-GIS is located on the following link (https://rainprague.vumop.cz/).

One of the causes of earth fill dam failure are internal erosion. To simulate these phenomena, a number of software are available to calculate the failure of an earth fill dams due to overtopping or due to internal erosion. For this purpose, software (SW) A Rapid Embankment Breach Analysis (AREBA) was chosen, for which a one-way sensitivity analysis was performed. The paper aims to understand the key geotechnical parameters input to the SW AREBA and their influence on the dam breach hydrogram, the size of the breach and also on the time characteristics. The most sensitive parameters influencing the outputs are the Manning´s roughness coefficient and the erodibility coefficient. These two parameters should be varied by the Monte-Carlo method in the AREBA.

The assessment of the energy performance of buildings depends on a large number of calculations, which must comply with the applicable legislation. The article presents the related structure of legal regulations, including standards and their brief characteristics.

Reducing the consumption of non-renewable raw materials has become a growing issue in recent years. The construction of constructed treatment wetlands generates a significant consumption of natural aggregates, which can be classified as non-renewable raw materials. For this reason, it is necessary to try to find alternative materials to natural aggregates. A substitute for conventional aggregates may be recycled construction materials, which are still not as widely used as natural materials, mainly due to their low quality. The currently available materials should be evaluated in terms of replacing the main filter material of vertical filters, as this is where the consumption of natural aggregates is highest. The aim is to ensure financial savings by using more affordable recyclates, but also to preserve sufficient natural resources for future generations.

The article provides findings from research on the duration of peak flow in an apartment building at all measurement days. The first part of the article describes the measurement of flows in an apartment building. Second part of the article describes an evaluation of the measured data in individual days in the apartment building. The third part of the article will discuss the evaluated results and a brings a summary by the author.

The aim of the article is to describe the main indicators that affect the amount of oxygen in wastewater and its overall quality. There are three environments that characterize wastewater according to the amount of oxygen. After using all the oxygen from the wastewater, negative phenomena often occur. For example, damage to the cement part of sewers, the formation of excessive odors in the environment or the negative impact of wastewater treatment. The article also includes measured values of the oxidation-reduction potential in a real pumping station in a combined sewer.

The use of SARS-CoV-2 RNA as a biomarker of COVID-19 in wastewater appears to be an appropriate tools for the establishment an early warning system for successful monitoring of infectious outbreaks before an epidemic occurs. SARS-CoV-2 viral RNA fragments are secreted by infected individuals in wastewater excrement, where they can be detected by the quantitative polymerase chain reaction (RT-qPCR) method. Within the project “Utilization of wastewater monitoring as an early warning tool against the emergence of an epidemiological situation” in 2021, wastewater sampling methods were optimized with subsequent verification of these methods on wastewater samples taken in subsequent waves of the epidemic.

The article deals with the influence of heat transfer between hot and cold water pipes on the growth of Legionella bacteria, which is a significant problem in hot water preparation and distribution systems. Legionella bacteria need a very specific environment for their formation, where systems for the preparation and distribution of hot water are the ideal place for its growth. The conditions for the growth of Legionella were investigated by numerical simulations of heat conduction in the calculation program CalA 4.0 Several variants differing in geometrical arrangement of the pipes and the thickness of the thermal insulation of the pipe were simulated. The results of the simulations confirm the need to insulate the water pipes in order to prevent the growth of Legionella.

The current trend and sustainable approach to reducing or eliminating carbon dioxide emissions lie in the use of renewable energy. According to ČSN EN 16147: 2011, the use of shower and bathtub accounts for approx. 48–75% of the total hot water demand, depending on the size and facilities of the household. [1] Some owners and operators are looking for new ways of recycling wastewater, which can be supplemented by obtaining thermal energy for preheating hot water or as a source of thermal energy for heat pumps in the case of hot greywater collection. This paper deals with a summary of laboratory procedures for testing technological units within the project “Collection and reuse of heat energy from wastewater, combined with the use of treated wastewater”.

This article focuses on the issue of measuring the temperature of water in water distribution networks. Under certain conditions, the increased water temperature can have a negative effect on the quality of drinking water, which in extreme cases can lead to the loss of the status of hygienic safety of drinking water. The article contains an overview of the negative consequences of increased water temperature on its quality, a clear presentation of all parts of the distribution system in which the water temperature can change and describes the existing procedures for measuring the water temperature. Part of the work is also a description of the proposed methodology for continuous measurement of water temperature in the distribution network, the feasibility of which was experimentally tested in laboratory conditions.

The aim of this research is a comprehensive evaluation of the retention capacity of the landscape depending on the use of soil protection technology in a selected locality and a comparison of selected hydropedological characteristics in the context of land management. The area is modeled in terms of erosion and runoff conditions. In the next stage, the plan is to evaluate the changes in selected physical hydropedological characteristics during the year in the conditions of climate change.

This work deals with research and development of a new grouting mortar with increased chemical resistance based on portland cement. The aim of this work is to verify new mixtures with specific admixtures. Resistance to attack by external sulphates was monitored, while the test specimens were placed in a sulphate solution of 29.8 g / l (44 g / l Na₂SO₄) according to DIN 19753. The results of the work show that the addition of the optimal amount of crystalline waterproofing admixture can achieve a significant increase in resistance to sulfate corrosion. Based on the obtained results, new mixtures will be proposed, optimized by the addition of suitable secondary raw materials.

Denitrifying bioreactors are used to remove nitrates from surface runoff in agricultural areas and thus to prevent them from entering surface water bodies. The course and rate of the denitrifying process is influenced by many factors. One of the most important ones is the inflow water quality, as the water can be contaminated also by pollutants such as pesticides.
We have paper proposed and optimized a methodology for the long-term testing of the effect of pesticides on the denitrification process. This batch test was performed to evaluate the inhibition of the denitrification rate. Apart from optimizing the nitrate dosage method, we determined as well their optimal dose (15 mg/l) and also the most suitable NaHCO₃ concentration in the deionized water (0.5 mg/l).

The paper deals with the requirements of the quality of potable cold water in water piping system inside buildings. The contribution focuses on temperatures, which should be provided in the water piping system and describes the main risks and factors influencing the temperature of cold water. The paper shows the basic measures and possible solutions of the problem of ensuring the sufficient potable water exchange in buildings. In buildings, there usually are not ideal conditions for ensuring the hygiene of potable water, the resulting hygienic risks can be reduced using the right technical solution.

Internal erosion is one of the most common causes of failure of hydraulic structures. A special case is a backward erosion piping during which an exceeding of critical hydraulic gradient occurs on the edge of the structure foundation interface. This becomes especially dangerous for the structure when the foundation consists of sand or very sandy soil that is very easy to erode. The sand property of erodibility is not yet fully described. In this paper, an experimental device used for the rate of erosion determination for a picked sand is presented as well as a calculation of the erosion coefficient which is usually used to describe soil erodibility. Furthermore, the paper contains critical hydraulic gradients during which the erosion occurred.

The second part deals with the properties of plastic pipes and their service life, describes CVPC pipes, PR-R pipes, ESC mechanism, chemical degradation, mechanical degradation, hinge spacing, inspections of old installations, certification of pipes, pouring into concrete, corrosion prevention measures, lowest criterion prices and conditions VdS CEA 4001.

The article focuses on the service life of pipes and sprinklers of sprinkler fixed fire extinguishing systems. Both components have a common enemy, which is corrosion. It appears in various forms and for various reasons.