General anomalies that occur in the management of apparent losses are identified and include determination of apparent loss indicators that fail to take into account both the random and bias errors inherent in metering. Estimating the volume of water losses that could be attributed to meter errors is also incorrectly assumed to be equivalent to the error limits (i.e. envelope) stipulated in standards. Performance indicators that are reliant on flow meter data must be expressed as a range and not as a single value which is common practice. It is shown that the measurement error range decreases as the number of meters increase when combining both their bias and random errors. A default value for reference annual apparent losses (RAAL) is quoted as 5% of the authorised consumption unless historic records can demonstrate otherwise. This 5% value relates to water meter errors that are only one component of apparent loss contributing to a volumetric imbalance and still requires inclusion of random errors in its calculation and therefore should be reported in the form of a range. Meter measurement errors include those of the meter fleet (e.g. revenue meters) as well as large (bulk supply) meters.
Yorkshire Water uses AQUASCAN TM2 for trunk main leak detection - Case Study
Introduction After initial meetings about suspected leakage and NRW losses with Craig Needham and Piotr Kozeil from Yorkshire Water a trial was arranged to use the GUTERMANN AQUASCAN TM2 correlator. An initial location on an 18” Cast Iron trunk main was identified from Longwood Service Reservoir feeding four large DMAs. Other leak detection methods had previously been carried out with a point of interest which were to be compared and followed up with the AQUASCAN TM2. Challenge The Cast Iron main had...
Global: Increasing Efficiency with Permanent Leakage Monitoring - Case Study
Abstract In this paper information from Water Authorities in the USA, Europe, Middle East and Australia that have purchased permanent monitoring leak detection equipment is reviewed and the findings are presented in a structured format that covers the following: Justification for permanent monitoring Evaluating the different product offerings Selecting the deployment zone Installation challenges Collection and validation of the data Handling false Alarms Managing the change in operational procedures Calc...
Israel/Haifa: Cutting water loss by more than half in a rigorous process - Case Study
Introduction Haifa is Israel’s third-largest city with a population of over 250,000. It is in the very north of Israel, close to the border to Lebanon and beautifully situated on the shores of the Mediterranean Sea. Mei Carmel is a public corporation founded in 2010 as a spin-off from the municipal government with the aim to improving the public service level to the residents of Haifa. Mei Carmel is obliged to invest all the excess profit in water and sanitation infrastructure. The entire pipe network...
Complex city structure in Taipei - 13 leakages detected - Taipei, Taiwan - Case Study
In 2014, Leif Koch, DHI, and Ramböll partnered with the Taipei Office of the Trade Council of Denmark and the Taiwan Water Corporation for a pilot project to reduce water loss in Taiwan. These organizations sent a team of leakage engineers and operators to work at a test site on Chijin Island.Leif Koch trained Taiwan Water Corporation staff in advanced leak detection methods and instruments so that the local Taiwanese staff could continue using Leif Koch’s strategies after the pilot project’s...
Unique Danish partnership against global water losses - Leakman, Denmark - Case Study
Nine Danish partners have formed a consortium with the objective to demonstrate the use and effect of integrated high-end solutions within Leakage Management based on Danish technologies and know-how. The nine partners represent leading technology providers, consultants, water utilities and the Technical University of Denmark. The project – named the LEAKman project – is initiated to demonstrate Danish solutions for reducing urban water loss and pave the way for new technological developments. It...