# The Impact Assessment of Water Supply DMA Formation on the Monitoring System Sensitivity
###### Abstract  
One of the main tasks that water companies face is limiting water losses through the distribution network. This issue is becoming more and more relevant because of progressive climate changes and rising water resource deficiencies. The first step to reducing water losses is the proper detection of leakages, including their location and size. A common approach, called active leakage control, is to divide the water network into District Metered Areas (DMAs) to detect unreported leaks in the water distribution system (WDS). The operating flow meter device at the border of the DMA allows the determination of the number of water losses by balancing water inflows into the zone and billed water consumption. However, to precisely locate a water leak it is necessary to equip the DMA with an adequate number of pressure sensors. The aim of this paper is to evaluate the impact of water supply DMA formation on the sensitivity of the monitoring system in accordance with the number and location of the pressure sensors and the geometric structure of the water pipes in the DMA in order to successfully detect water leakage. The research was conducted on a model grid network with a constant node number but a differential pipe structure. Subsequently, results were verified in the conditions of a real water supply network. The obtained tests showed no clear relationship between the effectiveness of leak detection and the network complexity but confirmed a significant improvement in leak detection after equipping the monitoring system with an additional pressure gauge. water distribution system; water supply networks; District Metered Area; monitoring system +
Footnote †: journal: Medical  
here, such as the use of hardware, biological and software-based systems [11; 12]. In all cases, the key role in the detection process is played by the proper arrangement of the measuring sensors used and the accuracy of their indications [13; 14]. A number of methods are used to locate these sensors [15; 16; 17; 18] which can be divided into heuristics and explicit and implicit methods [19]. One of the methods facilitating both the location of measuring sensors as well as the implementation of IT systems supporting the leak detection process is the division of water distribution systems into District Metered Area (DMA) zones [20; 21]. Many methods are used to locate these zones [22; 23; 24], including commercial software [25]. When determining DMA zones, parameters such as the number of water intake nodes, the number of connection nodes, the possibility of separating the zone from a larger distribution system with a minimum number of water supply sources for the zone, and the hydraulic conditions for the zone's operation under various water consumption scenarios are most often taken into account. For the assessment and location of leaks in these zones, water flow rate sensors are primarily used, including water meters for water consumers and manometers [26; 27; 28]. However, research carried out in real water supply networks shows that, despite the use of these sensors, there is a problem with the lack of leak detection [29; 30; 31; 32]. A frequent solution to this problem is to increase the number of sensors, as well as the additional use of acoustic or vibration sensors [33; 34; 35]. However, while limiting ourselves to pressure and flow sensors, it is worth asking whether the lack of leak detection is dependent on the degree of complexity of the geometric structures of water supply networks and whether it results from the measurement uncertainty of these sensors. According to the literature review, there is a research gap in analyses of the impact of the geometric structure complexity on the accuracy of leak detection combined with analyses of the measurement uncertainties of the devices used. In the present article, the authors attempt to find answers to the above issues.