Settlement development depends on many factors, including the availability of municipal infrastructure. Scientists find that only integrated municipal infrastructure planning and settlement-development planning create conditions for sustainable and economical urban development. This is not taken into account in spatial planning practise in Slovenia. This paper seeks a response to the research question: Based on what data, and based on what model can the capacity of the water supply system in Slovenia be assessed, which constitutes the expert basis for settlement development decision-making at the local level. To this end, we analysed the results of relevant existing research and devised an appropriate integrated and dynamic model for assessing the capacity of the water supply system, which was generated from a simulation of construction on vacant building land and relevant water requirements of new water consumers. In assessing the capacity of the public water supply system, the Aquis 7.0 Software was applied in accomplishing the hydraulic system validation. In line with the hydraulic system validation results, the respective measures are proposed, and the costs of necessary improvements of the existing water supply system or its upgrading are envisaged. The model was applied on the example of the Municipality of Kranj.

Water resources are facing increased stress owing to population growth and environmental pollution. Water utility companies are concerned about this, and they are increasingly utilizing decision support systems to achieve higher transparency in utility investment project selection and to improve the economic management of water supply systems and resource exploitation. However, utility investment project decisions involve a diverse set of quantitative and qualitative criteria. This makes the selection of an appropriate decision method difficult. We have developed a novel hybrid multi-criteria decision method that integrates quantitative and qualitative criteria value domains in the same decision-making model and applied it to a real-world case involving a large multi-utility operator. The method is based on the decision expert and multi-attribute utility theory methods, which were modified to facilitate conversion between criteria domains. Our innovative approach allows for the use of the expressive power and comprehensibility of the qualitative method while maintaining the precision of the quantitative method, enabling decision makers to differentiate more easily between worthwhile and less feasible utility investment projects in the field of safe drinking water supply. The proposed method is applicable to a wide range of decision problems involving a diverse set of decision criteria.

This study present an efficient graph-theoretical method for automatic design of district metered areas (DMAs) in water distribution networks (WDNs). The proposed method consists of two main parts, WDN partitioning and DMA connection, and is tested on a real-life WDN for which three spectral partitioning methods, multiple weight cases, and two clustering criteria are compared. The efficiency of the proposed DMA connection algorithm with respect to the traditional combinatorial approach is shown for different numbers of established DMAs. The final solution is selected according to a multicriteria evaluation model, which was developed in order to reduce the subjective influence in the selection process and considers hydraulic, cost, and topological criteria. The results show that all three tested spectral partitioning methods, i.e., the ratio cut, normalized cut, and newly proposed generalized normalized cut, are suitable for WDN partitioning and that the quality of the obtained solutions can be further improved by considering appropriate topological and cost-based WDN information in the partitioning process.

Settlement development depends on many factors, including the availability of municipal infrastructure. Scientists find that only integrated municipal infrastructure planning and settlement-development planning create conditions for sustainable and economical urban development. This is not taken into account in spatial planning practise in Slovenia. This paper seeks a response to the research question: Based on what data, and based on what model can the capacity of the water supply system in Slovenia be assessed, which constitutes the expert basis for settlement development decision-making at the local level. To this end, we analysed the results of relevant existing research and devised an appropriate integrated and dynamic model for assessing the capacity of the water supply system, which was generated from a simulation of construction on vacant building land and relevant water requirements of new water consumers. In assessing the capacity of the public water supply system, the Aquis 7.0 Software was applied in accomplishing the hydraulic system validation. In line with the hydraulic system validation results, the respective measures are proposed, and the costs of necessary improvements of the existing water supply system or its upgrading are envisaged. Based on the results obtained, the settlement-development stages can be determined. The model for assessing the capacity of the water supply system was applied to the example of the Municipality of Kranj.

V clanku bo prikazan vpliv spremembe rabe zemljisc zaradi naravnih ali antropogenih dejavnikov na povrsinski odtok in stanje podzemnih voda, s tem pa na poplavno nevarnost, ter vpliv na znižanje podzemne vode ob vodnjakih in s tem na (ne)varno delovanje vodooskrbnega sistema. Vplivi spreminjanja rabe zemljisc in gozdne zarasti na vodozbirnem obmocju na poplavno nevarnost ob reki Iski in vodarni Brest ter povezave med povrsinskimi in podzemnimi vodami ob visokih vodah in v susnem obdobju, od katerih je odvisno delovanje vodarne, ki oskrbuje Ig in Ljubljano z vodo, so bili analizirani s povezovanjem hidroloskega, hidravlicnega in hidrogeoloskega modeliranja. Obravnavali smo 27 scenarijev, ki poleg sprememb rabe zemljisc vkljucujejo tudi razlicne padavinske dogodke, vplive podnebnih sprememb ter naravnih nevarnosti (žled, lubadar) in clovekove posege v gozd (pogozdovanje). Prikazani so spremembe poplavne nevarnosti za poselitev na Iskem vrsaju in neugodni vplivi na oskrbo z vodo iz vodarne Brest. Posledice naravnih ali antropogenih sprememb rabe tal je z omilitvenimi ukrepi mogoce vsaj delno omejiti, opozoriti pa velja, da na obmocjih s pravnim režimom veljajo omejitve, prepovedi in zapovedi, ki vplivajo tudi na sanacijske ukrepe. Zato je treba slediti poti vode in v posameznih procesih ovrednotiti vir in stopnjo nevarnosti pri obicajnih razmerah in ob izrednih dogodkih.

We present an efficient graph-theoretical method for partitioning water distribution networks (WDNs) into district metered areas (DMAs). The proposed algorithm consists of two main parts, namely WDN partitioning and DMA connection, and is tested on a real-life WDN, for which different weight cases are compared. The efficiency of the proposed DMA connection algorithm, in regard to the traditional combinatorics approach, is shown for various numbers of established DMAs. The final solution is selected according to the multi-criteria evaluation model, which was developed in order to reduce the subjective influence in the selection process and considers hydraulic, cost, and topological criteria. The results show that the newly proposed spectral partitioning method, namely generalized normalized cut, is appropriate for WDN partitioning and that we can further improve the quality of the obtained solutions by considering appropriate topological and cost-based WDN information in the partitioning process. * Stik / Correspondence: daniel.kozelj@fgg.uni-lj.si © Zevnik J. et al.; Vsebina tega članka se sme uporabljati v skladu s pogoji licence Creative Commons Priznanje avtorstva – Nekomercialno – Deljenje pod enakimi pogoji 4.0. © Zevnik J. et al.; This is an open-access article distributed under the terms of the Creative Commons Attribution – Non Commercial – ShareAlike 4.0 Licence. https://doi.org/10.15292/acta.hydro.2018.03 Zevnik J. et al.: Učinkovita particija vodovodnih omrežij na merilna območja z uporabo teorije grafov – Efficient partitioning of water distribution networks using a graph-theoretical approach Acta hydrotechnica 31/54 (2018), 35‒50, Ljubljana 36

We present an efficient graph-theoretical method for partitioning water distribution networks (WDNs) into district metered areas (DMAs). The proposed algorithm consists of two main parts, namely WDN partitioning and DMA connection, and is tested on a real-life WDN, for which different weight cases are compared. The efficiency of the proposed DMA connection algorithm, in regard to the traditional combinatorics approach, is shown for various numbers of established DMAs. The final solution is selected according to the multi-criteria evaluation model, which was developed in order to reduce the subjective influence in the selection process and considers hydraulic, cost, and topological criteria. The results show that the newly proposed spectral partitioning method, namely generalized normalized cut, is appropriate for WDN partitioning and that we can further improve the quality of the obtained solutions by considering appropriate topological and cost-based WDN information in the partitioning process.

Due to their retention capacity, extensive flat floodplains have a significant impact on the propagation and transformation of flood waves. The conveyance and retention capacity of an area is significantly influenced by land use. The paper presents results of a hydraulic analysis of the impact of land use on the run-off regime in a retention area and consequently on flood wave propagation. The land use of the retention area was simulated by hydraulic roughness. The simulations were performed for flood waves with different values of peak discharge and with two lengths of duration. A spectrum of flood waves in which the retention areas have significant impact on the propagation was considered. To isolate the impact of topographical characteristics of riparian and retention areas on the communication of water between the channel and retention area, as well as on the formation of parallel streams in the area, a theoretical modelling area with simplified geometry was used in the first phase. Conclusions based on the results of the first-phase simulations were tested on a practical case of the plain Krško–Brežiško polje, where data from field measurements as well as data from the physical model were used in the numerical calibration of the model.

Inverse modelling concentrates on estimating water distribution system (WDS) model parameters that are not directly measurable, e.g. pipe roughness coefficients, which can, therefore, only be estimated by indirect approaches, i.e. inverse modelling. Estimation of the parameter and predictive uncertainty of WDS models is an essential part of the inverse modelling process. Recently, Markov Chain Monte Carlo (MCMC) simulations have gained in popularity in uncertainty analyses due to their effective and efficient exploration of posterior parameter probability density functions (pdf). A Bayesian framework is used to infer prior parameter information via a likelihood function to plausible ranges of posterior parameter pdf. Improved parameter and predictive uncertainty are achieved through the incorporation of prior pdf of parameter values and the use of a generalized likelihood function. We used three prior information sampling schemes to infer the pipe roughness coefficients of WDS models. A hypothetical case study and a real-world WDS case study were used to illustrate the strengths and weaknesses of a particular selection of a prior information pdf. The results obtained show that the level of parameter identifiability (i.e. sensitivity) is an important property for prior pdf selection.

The purpose of the research was to quantify characteristics of a subcritical flow at a rectangular sharp-crested side weir in a rectangular main channel using non-invasive measuring techniques based on the visualization of the flow. Experiments were carried out in physical models, including nine different dimensions of the side weir and nine combinations of the inflow and tailwater level for each weir, amounting to 81 test runs. Velocity vector fields were measured in various horizontal planes along the side weir using a high speed digital camera and electrolysis-induced hydrogen bubbles as flow tracers. Recorded films were converted into sequences of images which were used for numerical calculation of local velocities. Components of velocity vectors were determined with great spatial and time resolution. Longitudinal profiles of water surface elevation at each side weir were determined using photos of laser-induced vertical section planes. Measured discharges and flow depths were used to formulate new equation for the side weir discharge coefficient using dimensional analysis. The principal results indicated that velocity distribution along the side weir was distinctly non-uniform, with various velocity ratios increasing along the crest. However, the calculated energy grade line was parallel to the main channel bed, indicating that only friction losses were present. The proposed equations for the side weir discharge coefficient gave results that were in good accordance with two other studies.

The process of determining the residual hydropower potential of a certain river catchment or reach requires a sequence of methods from data acquisition (topography, hydrology etc.) to definition of different parameters such as hydropower efficiency. The level of detail of this process depends on the required level of decision-making. Until relatively recently, the determination of residual hydropower potential was performed manually. Nowadays with the developments in information technology, this process can be fully automated with significant time efficiency. Nonetheless, when a model is established, the process of input data verification must still be performed, which in some cases requires additional input data corrections. Furthermore, it can sometimes occur that original data, e.g. official data on river network, needs to be corrected. The article gives insight into the main steps and development of an informatics tool where the process of testing on real cases provides a good feedback to the developer. The presented tool, based on geographic information system, was developed within the project SEE Hydropower and it is estimated it will provide efficient support to the decision-making process at strategic level where multi-sector objectives are harmonized. Testing of the developed tool and result interpretation were performed and verified on real case study areas.

In this paper we discuss sampling design for the calibration of water distribution system hydraulic models. The sampling design for the calibration of water distribution-system models is formulated as an optimisation problem consisting of two normalised objective functions. The first objective function is used to increase the calibration accuracy of the model parameters, and the second one is used to reduce the number of necessary measurement locations. The optimisation problem was solved by using genetic algorithms. The verification and application of the developed optimisation model (called IMMe) were carried out on the artificial water distribution system of Anytown, which serves as a reference model for testing various researches in hydraulic modelling. The verified IMMe model was applied to a real water-distribution system in the town of Sezana. For both water distribution models, the use of genetic algorithms proved very efficient with extremely combinatorial optimisation problems. The developed calibration and sampling design allow very accurate hydraulic modelling of the water distribution systems, which is of key importance for ensuring the economy and efficiency of drinking-water supplies in the future.

In the frame of an international established project called Sustainable Sediment Man- agement of Alpine Reservoirs considering ecological and economical aspects (here- inafter Alpreserv project) several typical reservoirs were selected for pilot projects. The activities are focused on different strategies to transfer or remove sediments in a larger scale taking into consideration the fragile environment of the Alps. The measurements in those pilot projects are accompanied by extended measurements of biotic and non-biotic parameters using experiences from different nations and competent authorities. Information of sed- iment removal efforts throughout the Alps will add valuable data not only for project but also for future management tasks. One of mayor results of the Alp- reserv project is the established database which will support several activities from collecting to analysis of information on res- ervoirs of different geometry and opera- tional procedures. By means of intensive cooperation within the partner network database could be extended by collecting datasets of several monitoring stations or from other sources if applicable. Proactive collaboration of the in- Abstract In order to facilitate access and sharing of the information on the reservoirs Alp- reserv database was created. The database enables storage of data in large quanti- ties and extent data mining and also successful editing and technical administration of the collected data. At the first stage the Alpreserv database was prepared and tested on a simplified level and the extent of data has been reduced. At this level Alpreserv database is already accessible on the Alpreserv homepage by using the Alpreserv database application. So far the data of seven pilot action projects has been collected.