Non Revenue Water Formula

Water balance iwa concept system input volume siv 1715 8 100 authorised consumption 1289 1 75 13 rw 1282 4 74 74 non revenue water nrw 433 4 25 26.

Non revenue water formula. Non revenue water spaghetti network repairs and leaks. Management of non revenue water be it at a national level or site specific. Water audit is a way to find the revenue and non revenue water. This has a serious effect on the financial viability of water utilities through lost revenue lost water resources and increased operational costs reducing their capacity to fund necessary expansions of service especially for the poor.

It is estimated that each year more than 32 billion m3 of treated water are lost through leakage from distribution networks usaid wbi 2010. The global volume of non revenue water nrw is staggering. This percentage includes real or physical losses like water leakage and apparent losses such as illegal connections and meter inaccuracies. A water audit determines the amount of water lost from a water supply system and the cost of this loss to the utility.

Losses can be real losses through leaks sometimes also referred to as physical losses or apparent losses for example through theft or metering inaccuracies. Non revenue water nrw in a water distribution network which has been recently introduced by the iwa instead of unaccounted for water ufw farley and trow 2003 is defined as the difference between total inflow to the system and total metered and authorized un metered consumptions. An additional 16 billion m3 per year is estimated as delivered to customers but not invoiced because of theft. Nrw is divided into two parts apparent and real losses.

The amount of water billed to consumers is known as non revenue water nrw. High levels of nrw are detrimental to the financial viability of water utilities as well to the quality of water itself. Non revenue water nrw is water that has been produced and is lost before it reaches the customer. Unbilled authorized consumption usually a minor component of water balance apparent losses and real losses.