Traditional water use forecasting methodologies have been based primarily upon extrapolation of historical trends into the future, using either single or multidimensional regression analysis. However mathematically eloquent, these techniques are in many cases today totally inadequate for providing planners and decision makers with meaningful guidance on expected future water use.
The primary reason for this lies with the pure and simple fact that in more and more cases within the United States, the ‘limits to growth’ concepts are beginning to be felt in both the heavy water using portions of the economy and the portions not related to water. The direct and indirect effects of this on future water use are impossible to predict with any confidence by using forecasting techniques based on the analysis and extrapolation of historical trends. To correct this, the following basic concepts should guide the development and utilization of future water use forecasting procedures.