This paper identifies the adverse events occurring during the execution of water supply and sewerage systems construction. The basis for this paper is research conducted in 2010-2014 on the construction sites of water supply and sewerage systems located in the provinces of Lower Silesia and Opole. The research consisted of direct observations of construction sites and review of construction documentation. It showed that work stoppages on the examined construction sites were frequent. They were caused by violations of work discipline by the production employees, adverse weather conditions, and defects in the project documentation. The study demonstrated that in almost every case, these bad an adverse effect on the completion date and budget of the investment. The analyses show that in such important and expensive investments as water supply and sewerage systems, organizational structures in which a special role is assigned to middle-rank personnel should be adopted.

The purpose of this study is to solve the efficiency and reliability problems of upstream water intake structures for energy and irrigation systems in the region of the Republic of Azerbaijan. Among the methods used in the study, experimental, analytical, and modelling methods should be distinguished. During the study, analyses and field investigations of main structures, and energy and irrigation systems in the foothills were conducted to identify the reasons for the low efficiency and reliability of existing old water intake structures and reduce their negative impact on the environment. The results of the study showed that many water intake structures built on small rivers are not only in poor working condition but also do not meet modern environmental requirements. Many of these structures were built more than thirty years ago and have not been modernized or reconstructed in accordance with new technologies and requirements. As a result of the study, recommendations were prepared for the design of new water intake structures that meet all modern environmental requirements and guarantee the more efficient use of water resources. These new facilities will also help to reduce water losses during the overflow process, which will make the use of water more cost-effective. Additionally, one of the main outcomes is the developed useful model, which pertains to the field of hydroengineering construction for water intake from mountain and foothill rivers, serving as an additional barrier to reduce the influx of large sediment into the reservoir.

In the paper the issue connected with water network failure regarding the soil conditions was presented. Water pipes constitute a large part of water company asset. Therefore the analysis concerning the influence of soil conditions into failure occurrence of water pipe is crucial for proper functioning of water supply systems (WSS). In the performed studies the real data from the operation of the exemplary WSS was obtained. The following properties of the ground conditions were taken into consideration among others: the chemical composition and ground phase, based on analysis performed through the following equipment, as the electron microscope with X-ray spectrometer detector and backscattered electrons (BSE) using the powder Debye-Sherrer’s method and X-ray diffractometer. The analysis indicate dependence between soil conditions and corrosivity occurrence, what indicate the importance of performed analysis.

The purpose of this article is to present a new bell type water well construction with circulating treatment and its application. The construction of the water well has been developed and research has been conducted using physical and electrical modelling as well as in the practical field. Researches in this work are of analytical and experimental character. As the results of the research, optimal physical parameters of the constructions have been found and analytical  empirical formulae have been derived to calculate hydraulic parameters. Recommendation for application has been presented. The results received in this work can be used for the application of well construction. Further research is required to improve the physical and the hydraulic parameters of the proposed construction. The work has scientific and practical interest.

Access to clean and sufficient drinking water is difficult in much of Ethiopia’s Afar Region. It is observed that many schemes in the region are non-functional. The study was conducted to overcome the observed problem in seven selected districts of the region. The study regarded hand-dug wells and roof water collection systems, which are the two most common features in the research areas. Eight hand-dug wells and sixteen roof water harvestings are purposively included in the study. All the water points are constructed by Kelem Ethiopia which is a non-governmental organisation and the foremost local organisation for the communities. As per the research survey, the average functional status of the hand-dug well schemes is 65.75% and the roof water harvesting schemes is 22.94%. The research was based on the qualitative data collected on site. The hand-dug well sites were evaluated using 10 parameters, and the roof water harvesting schemes were analysed using 12 parameters. The main non-functional aspects of the scheme are lack of community ownership, drying up of water sources, lack of maintenance and rehabilitation, poor coordination of beneficiaries and school roofs blowing off. Most schemes still require minor to major maintenance and rehabilitation. According to the research, the solutions for water supply are identified in relation to the desired objective.

Challenges with respect to potable water supply in Vhembe District threaten the health and welfare of local community. This paper is aimed at assessing the challenges and residents’ coping strategies to improve the potable water supply systems in rural areas in Vhembe District Municipality (VDM). Data for this paper was collected from households, councillors, traditional leaders and municipal officials through questionnaires, interviews and focus-group discussions. Qualitative and quantitative research methods were used and thematic content analysis and descriptive statistics were used to analyse data. The results showed that the main sources of water are ground water from boreholes which are used by about 45.3% of the communities, followed by tap water from the dams, by 35.3%, then rivers by 4.0%, fountains by 5.4% and water tankers by 10.0%. Among the identified challenges are: aged water infrastructure, system breakdowns, lack of funding, vandalism of infrastructure and lack of maintenance, operation of infrastructure by unskilled technicians, theft, and non-payment of water services, among others. To cope with water supply challenges, the study recommended that communities play active role in water projects which would include paying of water supply service for its sustainability. They should also play active roles in water committees that will manage, operate and maintain the water supply with the assistance of VDM officials. It was concluded that the rural water supply situation can be improved when communities, government and other relevant stakeholders cooperate and provide solutions and resources.

The use of non-centralised water supply in remote settlements is currently the only possible option. Monitoring the wa-ter quality of such supply sources is a complicated task in such areas, especially when there are active karst processes and difficult groundwater conditions. The application of deterministic analytical models of water supply under the risk of dis-turbance to groundwater dynamics is not efficient. Significant quantitative and even qualitative changes in groundwater conditions may take place between the calculated points, and the underestimation of these changes in expectation-driven computation models may result in serious geoecological issues. This research studied and justifies the use of adaptive dy-namic hydrogeological control in an area of non-centralised water supply based on the identification of key zones of geo-dynamic karst monitoring and the electrical express-monitoring of water resources. The identification of key zones is based on an integrated analysis of available groundwater information that describes changes in groundwater hydrodynamic condi-tions at the time of the karst forecast. The development of karst-suffusion processes is accompanied by more intense dy-namic changes in local areas of geologic environment compared to the general variation in intensity. Information about the occurrence of destructive groundwater processes by means of selective geodynamic monitoring may thus be obtained much earlier than with environmental geodynamics monitoring as a whole. The experimental hydrogeological control of an area of non-centralised water supply was conducted on the right bank of the Oka River in Nizhny Novgorod region, a locality with an active manifestation of karst processes. Structure and algorithms of space-time processing of hydrogeological con-trol data developed by authors have been used. The approach based on multifrequency vertical electrical sounding (MFVES) method has shown good correspondence with direct borehole observation when measuring depth of the first aq-uifer. Zones of unsafe water use have been revealed. The results demonstrated the effectiveness of the proposed method and the need for further regular observations of destructive groundwater processes by means of selective hydrogeodynamic monitoring.

The growing population and the development of industries in all countries of the world have created a very important and complex issue for water supply to cities. Today, many parts of the world are facing the problem of water shortage and this problem cannot be easily solved. In addition to the proper use of water resources and preventing the loss of natural water, the establishment of regional water supply networks is effective in meeting the future needs of the people. A water distribution network (water supply network) is a set of interconnected pipelines used to transport and distribute water in a complex. In designing the water distribution network, factors such as the type of water distribution network, water pressure, water velocity, design flow, minimum pipe diameter, pipe material and many other factors should be considered. In this study, we have tried to design the water supply network of a part of Balikpapan city in Indonesia. The design method led to the determination of pressure values in the connection nodes, pipe diameters, flow rate and velocity in the pipes. All the existing criteria are considered in the design of the water supply network. Although this study has been implemented for a specific study area, it can be of great help to designers in designing the water supply network.

Strengthening the functioning of existing rural piped water supply systems is a critical strategy for ensuring household water security, particularly in water-scarce contexts. Improving operation and maintenance (O&M) of the systems is an important area of focus, commonly plagued by poor reliability and functionality over time. From an economic perspective, there is an opportunity to optimise O&M input efficiencies as a foundation for improved management. This paper presented challenges and opportunities to optimise O&M input efficiencies based on an analysis of water supply systems in Vietnam’s highland areas characterised by mountainous terrain and water scarcity. The analysis focused on state-based agencies for O&M given their mandate for restoring the inefficient systems and identified input norms for guidance on how to optimise O&M activities. We applied an input-oriented data envelopment analysis (DEA) model under constant returns to scale assumption to estimate technical, economic and allocative efficiencies. The results identified efficiency levels of 90%, 30% and 33% respectively. The study suggests a 10% reduction in general input amounts and identified efficient input target values reveal potential reduction rates for technical labour (12%), electricity (12%), as well as the technical and economic norms of technical labour (0.86 person- day∙(100 m³)^–1 water sold) and electricity (0.53 kWh∙m^–3 water sold). The policy implications for O&M state-based agencies include the adoption of input-based contracting mechanisms, while the government is encouraged to approve water tariffs and provide compensation based on input items to promote water service supply as a public good in water- scarce and challenging areas.

Exploring the drivers of changes in ecosystem services is crucial to maintain ecosystem functionality, especially in the diverse Central Citarum watershed. This study utilises the integrated valuation of ecosystem service and trade-offs (InVEST) model and multiscale geographically weighted regression (MGWR) model to examine ecosystem services patterns from 2006 to 2018. The InVEST is a hydrological model to calculate water availability and evaluate benefits provided by nature through simulating alterations in the amount of water yields driven by land use/cover changes. Economic, topographic, climate, and vegetation factors are considered, with an emphasis on their essential components. The presence of a geographical link between dependent and explanatory variables was investigated using a multiscale geographic weighted regression model. The MGWR model is employed to analyse spatial impacts. The integration of both models simplified the process and enhanced its understanding. The findings reveal the following patterns: 1) decreasing land cover and increasing ecosystem services demand in the watershed, along with a decline in water yield, e.g. certain sub-districts encounter water scarcity, while others have abundant water resources; 2) the impact of natural factors on water yield shifts along vegetation > climate > topography (2006) changes to climate > vegetation > topography (2018).