55be9034d4 Utilities should then seek to control excessive losses to levels that are economic for the water utility. In 1999 the California Urban Water Conservation Council identified a 10 percent benchmark for non-revenue water.. Pitfalls of programs. Water industry facts and figures ^ American Water Works Association, M36 Publication, 3rd Edition,  Water Audits and Loss Control Programs, 2009 ^ Richard G. Often a distinction is made between unvalidated and validated water audits. Unvalidated water audits are desktop studies that include many estimates and their results can have an error range for real losses of +/- 50% or more. Overview of NRW levels. Retrieved 7 May 2012. Expressed as a share of produced water. 53-54 ^ American Water Works Association:Water Loss Control, retrieved on May 2, 2013 ^ American Water Works Association:M36: Water Audits & Loss Control Programs manual, Third Edition, retrieved on May 2, 2013 ^ a b International Benchmarking Network for Water and Sanitation(IB-NET): Non-Revenue Water at the International Benchmarking Network for Water and Sanitation Utilities (IB-NET) ^ Water 21, Journal of the IWA, April 2006, p. From a public health and drinking water quality point of view it is being argued that the level of real water losses should be as low as possible, independently of economic or financial considerations, in order to minimize the risk of drinking water contamination in the distribution network. Pearson and S.W.
Non revenue water (NRW) is water that has been produced and is lost before it reaches the customer. There are fewer financial incentives for a utility to reduce NRW if water production is cheap, if there is no or little metering (so that revenues thus are independent of actual consumption), or if volumetric tariffs are low. Engineers: it is more fun to design treatment plants than to fix pipes buried under the road. 123 ^ Jakarta Water Supply Regulatory Body:The First Ten Years of Implementation of the Jakarta Water Supply 25-Year Concession Agreement (1998-2008) (A Draft Translation), by Achmad Lanti, Firdaus Ali, Agus Kretarto, Riant Nugroho, Andi Zulfikar as Board Members of the Jakarta Water Supply Regulatory Body Period 2005-2008, 2009, p. NRW components and audits. Reducing apparent losses from illegal connections is often beyond what a utility can achieve by itself, because it requires a high level of political support. Metering of water use at the level of production (wells, bulk water supply), at key points in the distribution network and for consumers is essential to estimate levels of NRW (see Water metering). v ^ a b Lahlou, Zacharia M.: Leak Detection and Water Loss Control, National Drinkingwater Clearinghouse at West Virginia University, 2001, p. The International Benchmarking Network for Water and Sanitation recommends to use different indicators (percentage, losses per connection or losses per km of network) together. Losses per kilometer of network are more appropriate to benchmark real losses, while losses per connection are more appropriate to benchmark apparent losses.