Loss and Reuse

Loss Rate (%)

Loss Rate includes distribution losses within a demand site and otherwise unaccounted for demands. For example, in municipal systems, distribution losses could represent physical leaks, unmetered water use in public parks and buildings, clandestine connections, water used for line flushing, or water use for firefighting. The effect of distribution losses is to increase the supply requirement by the factor 1 / (1 - loss rate). NB: Do not include losses that are already accounted for as transmission link losses. Also, do not confuse these losses with Consumption--Loss Rate increases supply requirements but is not lost from the system, whereas Consumption is lost from the system and will decrease the return flow of the amount supplied.

Reuse Rate (%)

Reuse Rate accounts for water recycling or reuse. This adjustment refers to processes by which water is used in more than one application before discharge. For example, irrigation water may be routed for reuse in more than one field. In industry, water may be recycled for multiple uses. The effect of reuse is to reduce the supply requirement by the factor (1 - reuse rate). NB: This internal reuse should not be confused with the direct reuse by one demand site of wastewater from another demand site. See Return Flow Routing for more information on this non-internal reuse. The internal reuse happens within one demand site.

Taking all these factors into account (and DSM Savings),

  MonthlySupplyRequirement = MonthlyDemand x (1 - ReuseRate) x (1 - DSMSavings) / (1 - LossRate)

Entered on: Data View, Branch: Demand Sites, Category: Loss and Reuse, Tabs: Loss Rate, Reuse Rate