Estimating Opportunity Cost as A Tool to Evaluate Water Loss Management of Non-Revenue Water at PDAM Tirta Khatulistiwa

Water loss or Non-Revenue Water (NRW) is a national problem PDAMs, including PDAM Tirta Khatulistiwa. In fact, with a high level of water loss, there is a significant potential loss of income. This study aims to implement opportunity cost calculation as a managerial tool for PDAM Tirta Khatulistiwa in making investment decisions to improve water loss management. This research was conducted by collecting information from financial, managerial, and local government equity participation reports. Then the data reduction is carried out and calculated based on the gross margin, net profit margin, and the opportunity cost. This study indicates that the capital investment provided by the Pontianak City’s government has increased, followed by an increase in the number of consumers. However, it was not followed by an increase in the company’s profit. This is due to the opportunity cost or lost income during the business process amounting to Rp31,218,673,384.64 in 2019 with a potential income to Rp222,663,258,365.00 if it manages to suppress distribution leakage to the level of 20%. This potential income is worthy of consideration for PDAM Tirta Khatulistiwa to start water loss management in the NRW reduction program.

Determination of Economic Leakage Level with Optimization Algorithm in Water Distribution Systems

It is necessary to set the most appropriate targets in water loss management (WLM) and to choose the most economically and technically suitable method to achieve these targets. The aim of this work is to define the level of economic leakage with the optimization algorithm in sustainable WLM, considering the system components, requirements and costs of the methods. For this purpose, a new model based on discrete stochastic optimization has been developed to determine the most appropriate values of the pressure level and the number of teams. After the system components were entered into the model, the optimal values of parameters were determined according to the problem-specific defined objective function. It was calculated that the pressure should be reduced from 40[Formula: see text]m to 25.30[Formula: see text]m, and the number of teams was 4 for the sample system. The Economic Leakage Level for the system was calculated as 145.85[Formula: see text]m3/day in volume and 11.9% in percentage.

Water Loss Management in Small Municipalities: The Situation in Tyrol

Water losses in water distribution networks (WDNs) are unavoidable. Water losses are evaluated based on performance indicators (PIs) and used for future recommendations for network operators to take measures against water losses. However, these evaluations primarily focus on large and medium sized WDN and do not deal with the challenges of small WDNs (e.g., technical, and financial limitations, missing data). Therefore, an appropriate water loss management is a major challenge for operators in the federal state of Tyrol (Austria) due to the high number of small WDNs, e.g., low income in combination with long network lengths. In this regard, this work specifies and discusses state funding in Austria to support network operators to reduce water losses. To assess the impacts on management strategies, 40 WDNs, supplying 200 to 16,000 inhabitants, are investigated in detail. As the comparison of different PIs shows, a volume related PI (e.g., water loss volume divided by total water demand) is recommend as the decision criterion for local authorities due to minimal efforts and its easy calculation. Moreover, public funding helps to significantly reduce water losses in individual systems, but countermeasures should be different for small and larger WDNs. For example, leakage detection campaigns and rehabilitation planning based on pipe age should be established in future for larger WDNs in Tyrol. In contrast, an online flow metering system to monitor system inflows is suggested for small WDNs. Based on measurement data, leakages and burst can be detected and repaired swiftly.

q-Rung Orthopair Fuzzy Geometric Aggregation Operators Based on Generalized and Group-Generalized Parameters with Application to Water Loss Management

The notions of fuzzy set (FS) and intuitionistic fuzzy set (IFS) make a major contribution to dealing with practical situations in an indeterminate and imprecise framework, but there are some limitations. Pythagorean fuzzy set (PFS) is an extended form of the IFS, in which degree of truthness and degree of falsity meet the condition 0≤Θ˘2(x)+K2(x)≤1. Another extension of PFS is a q´-rung orthopair fuzzy set (q´-ROFS), in which truthness degree and falsity degree meet the condition 0≤Θ˘q´(x)+Kq´(x)≤1,(q´≥1), so they can characterize the scope of imprecise information in more comprehensive way. q´-ROFS theory is superior to FS, IFS, and PFS theory with distinguished characteristics. This study develops a few aggregation operators (AOs) for the fusion of q´-ROF information and introduces a new approach to decision-making based on the proposed operators. In the framework of this investigation, the idea of a generalized parameter is integrated into the q´-ROFS theory and different generalized q´-ROF geometric aggregation operators are presented. Subsequently, the AOs are extended to a “group-based generalized parameter”, with the perception of different specialists/decision makers. We developed q´-ROF geometric aggregation operator under generalized parameter and q´-ROF geometric aggregation operator under group-based generalized parameter. Increased water requirements, in parallel with water scarcity, force water utilities in developing countries to follow complex operating techniques for the distribution of the available amounts of water. Reducing water losses from water supply systems can help to bridge the gap between supply and demand. Finally, a decision-making approach based on the proposed operator is being built to solve the problems under the q´-ROF environment. An illustrative example related to water loss management has been given to show the validity of the developed method. Comparison analysis between the proposed and the existing operators have been performed in term of counter-intuitive cases for showing the liability and dominance of proposed techniques to the existing one is also considered.