District metering solutions for drinking water networks

  • What is District Metering?
  • Schematic diagram
  • Contributions

Preserving water resources, monitoring volumes flowing through networks, locating leaks, making savings and reducing unbilled water volumes are some of the daily concerns of contract operators. Network district metering offers an effective solution to this permanent challenge. 

 

 

The principle of district metering is to measure distributed drinking water and the water leaving the network (billed water) and to divide the network into consistent sectors (500 to 3000 subscribers). The volume of water is also measured when it enters and leaves each sector in order to improve knowledge of the network. Remote meter reading with SOFREL LS data loggers very quickly detects the appearance of a leak and guides the network maintenance teams to the leaking sector.

Data and calculations (average/min./max. flow, night flow) performed by the data logger are regularly transmitted via the GSM/GPRS network to the central systems for analysis. Daily processing of district metering data obtained through telemetry and SCADA has become a key factor in reducing water losses and improving network output.

 

Remote reading for district meters

 
Drinking water distribution networks are increasingly instrumented. Measuring points can pose problems of accessibility, depending on the area of networks and the number of sectors. By optimizing transmission costs and operating autonomy over several years, SOFREL LS data loggers eliminate this constraint of distance. Remote reading of meter indexes or flow meters is supplemented by the transmission of calculations and measurements such as:
 
  • daily volumes distributed in the network,
• night-time volumes according to time slots,
• minimum, maximum and average flows,
• pressure readings, etc.

 

This data remotely provides a permanent view of volumes of water passing through different network sectors and cuts running costs (no more manual meter reading rounds). So-called "major consumer" customers have a strong influence on the distribution network. Remote reading and reckoning of their consumption is thus needed to carry out network diagnostics.

 

 

 

 

Leak detection

The SOFREL LS data logger records the flow of water passing through the different sectors of the network 24/7. The calculations made on site by the data logger, particularly minimum and night flows, are  key indicators in leak detection. Once this information has been transmitted to the centralisation system, it is then possible to analyse changes over time and to cross-check the data from each sector in order to detect leaks in the network.
 
In order to ensure optimal responsiveness in the event of detection of a leak, it is possible to define thresholds for monitoring average measurements and flows. If one of these thresholds is exceeded, suggesting a leak in the network, data will be sent to the central stations and an alarm message forwarded to a mobile telephone. As a tool for leak detection, the GSM/GPRS SOFREL LS data logger helps to  limit water loss and considerably improves network output.
 

Network diagnostics

 

The SOFREL LS data logger helps the operator with  overall network diagnostics and analysis work. The measurement of pipe pressure enables the detection of network faults such as excess pressure. In the event of high variations in certain sectors of the network, LS immediately alerts the central system and sends an alarm SMS. The analysis of pressure being exerted on the network together with the diagnostic of all sectors enables corrective measures to be taken in order to prevent pipe breakage and reduce the flow from diffuse leaks.