Water utility planning efforts are becoming increasingly difficult throughout the world. Located in a semi-arid region, Ciudad Juárez, Mexico is a fast growing municipality that faces both physical infrastructure and water supply constraints. This paper examines monthly water consumption in Ciudad Juárez utilizing a linear transfer function procedure (LTF). Analysis is carried out for per customer usage and for the total number of municipal water system accounts. Models estimated for both series are subjected to a series of simulation benchmark tests. Findings suggest that water consumption in Ciudad Juárez reacts quickly to changes in economic and weather conditions. Out-of-sample simulation results are mixed. Per customer usage forecasts do not fare as well as those for total customers relative to random walk benchmarks.