Gutermann - Fixed Water Network Monitoring Solutions
In an ideal world, a water utility will control its NRW rate in two ways: (1) by reducing the number of larger leaks and pipe bursts by finding and fixing small leaks as early as possible, and (2) by minimising the leak run rate of each individual non-surfacing leak. We call this proactive leak monitoring. A utility wants to know about each leak in the distribution network: When does it appear. Where exactly is it. Is it stable or does it grow. Is the audible loud noise a leak at all, or is it another constant noise source.
The solution is to permanently deploy noise sensors (loggers) along the pipe network. In order to do this with a stand-alone system, independent of third-party data transmission networks, the following three dimensions have to be fulfilled:
(1) Sensor design: They are small enough to fit into valve chambers, they are non-intrusive (magnetic connection) and they are energy independent for a long period of time (at least 5 years). Integrated, cable-free units are preferable over a multi-entity, cable-connected construction.
(2) Full Correlation: The loggers have to have a correlation function in order to (1) filter out non-leak noise sources thereby reducing the amount of false alarms, and (2) pinpoint the exact location of the leak in order to minimise the time leakage crews take to locate the position of the leak. In order to correlate data from different sensors you must have two things: (1) entire noise recordings to provide enough data for in-depth data analysis – not just noise level amplitudes, and (2) a synchronisation of those recordings to less than a milli-second. The most crucial part, however, is the automatic correlation of the data every day. Manual correlation is not sufficient to detect leaks that are undetectable through noise-level analysis.
(3) Finally, if the sensors are placed below ground in tight chambers, the only way (today) to get the enough data out of the ground and onto the servers where the correlation analysis is done is via low-powered public radio frequency. There is not enough reliable cellular, FM radio or GPS connectivity below the chamber lids to help with the correlation.