Leak detection is more vital than ever

A leakage patrol can be carried out in specific areas using the Permalog "Patroller" module to detect, decode and analyze signals from loggers.

Water suppliers are under increasing pressure to reduce leakage rates and provide a consistent, high integrity water supply. Resource development is expensive and reductions in unaccounted-for water are an attractive and economically viable means of increasing the headroom between supply and demand. New techniques in leak detection are emerging to help water suppliers achieve their objectives.

Palmer Environmental, in conjunction with Hetek Solutions Inc., has recently launched the Permalog leak localization system which is the first that can be justified economically for permanent/semi-permanent installation. With leakage levels being legislated in the UK, initial trials in a major UK water company have shown the potential of Permalog to reduce leakage to record low levels and for water suppliers to maintain these over a 10 year period at low cost and with significantly improved customer service.

Permalog units are deployed throughout the distribution system to provide continuous surveying of leakage. Easily installed on main lines and hydrant valves, they are retained in place by a strong magnet and are battery-powered for at least 10 years. Loggers are immersion-tested to IP68 and will continue to operate even in flooded chambers with no maintenance required.

Each unit adapts itself automatically to its environment. If no leak is present a signal is transmitted to indicate normal background conditions. However, as soon as a possible leak is detected, the Permalog unit enters an alarm state and transmits leak data.

Following a rise in the nightline, or at standard periodic intervals, a leakage patrol can be carried out in specific areas using the Permalog "Patroller" module. This detects, decodes and analyzes signals from loggers to identify the location of units in leak mode and thereby the approximate position of the leaks. These data are indicated audibly, displayed on the LCD screen and stored in memory. Leak locations can be investigated during, or at the end of, the patrol. Leak data are printed out or downloaded to a PC, enabling correlation to be concentrated solely on suspect areas.

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