Why is more not done to reduce losses?
The answer lies largely in the saying: “out of sight, out of mind”. The simple truth is that very few leaks actually come to the surface. Mostly the water is carried away in adjacent sewers or other utility pipes. If an active attempt is not made to control the situation, it rapidly gets out of hand. But how is it possible to locate a small hole, a few millimetres wide, in hundreds of kilometres of pipes? The solution involves dividing the whole into parts, referred to as districts, each permanently created and ideally supplied by a single pipe on which is installed a flow meter and where possible also a pressure regulating valve. In this way the leakage level can be quantified regularly, and the presence and location of a new leak identified immediately.
Dividing a complex and interconnected web of pipes which forms a water network, is not an easy task. If not undertaken with care, it could result in seriously lowering the quality of service to the consumer. The answer is found in the creation and validation of a mathematical simulation model which represents the real system in all of its key characteristics. In this way, the optimum configuration can be determined even before the sectors are even created in the field. Once established they allow the situation to be continuously monitored and identify immediately the presence of a new burst and locate it quickly
Thanks to the extensive experience and great expertise of the staff of iWED Ltd., not least its founder who was involved in the development of the optimum approach, it has been possible to recover billions of litres / year of leakage in networks all over the world. Click here for more details.
How to reduce losses?
The solution requires the creation of permanent districts ideally supplied by a single pipe on which is installed a flow meter and a pressure regulating valve. In this way it is possible not only to quantify continuously the leakage level, but identify immediately the presence of a new burst and where it is located, thus simplifying the detection activity.
The structure of a hydraulic model is created from the network maps and customer consumption billing records. It is important to remember that even if the historical databases are not completely accurate and updated, a model can still be useful – provided of course that it is fully calibrated. This is done by comparing the calculated pressures and flows with those measured in the real network. Any difference is due to an incomplete knowledge and must be resolved. Only when the model reliably simulates the reality can it be applied to design the permanent leakage and pressure control system. Calibrating a hydraulic model requires great expertise. The staff of iWED Ltd has the experience of successfully constructed and calibrated well over 100 hydraulic models worldwide.
The creation of the districts also allows the effective control of pressure which not only lowers the leakage level but just as importantly reduce the burst frequency. This doesn’t mean however that the largest burst should not be located and eliminated. This can be done by applying specially developed acoustic instruments in the leakiest parts of the districts.
iWED Ltd. has the necessary expertise and experience to undertake all aspects of a water loss project including mapping and GIS, field monitoring, hydraulic and water quality model construction and calibration, design and construction of permanent leakage and pressure management systems, execution of step tests, application of acoustic leakage detection instruments and the long-term monitoring. For more information on how iWED Ltd. can be of assistance contact [email protected]