AWWA JAW34247

Virtually all variables used to forecast water demand are uncertain: population and household formation, employment and industrial growth, income and water use characteristics by customer sectors, conservation targets and performances, and weather. The key to accurate forecasting is to isolate or specify the effects of each variable so that changes in water demand that are attributable to changes in the variables over time can be accurately included in the forecasts. After a forecasting model has been properly specified, it is far more efficient to recognize the inherent error level and work with it to identify upper and lower bounds of potential water demand than to persist in fine-tuning the model to extract the last ounce of efficiency from a limited database. The objective of this article is to briefly discuss the major methods of demand forecasting and then concentrate on measuring conservation performance and integrating conservation targets into long-run demand projections. Includes 10 references, figures.