Weather Effects on Daily Water Use in New York City

New York City transports drinking water from distant surface reservoirs. Accurate understanding of the cityʹs water demand pattern is needed to identify possible conservation measures and plan future water supply projects. Previous studies of other U.S. cities have suggested that weather conditions affect daily water use. This hypothesis is studied through the daily water use data for New York City from 1982 to 1991. It is found that, during the winter months, weather has little effect on water use, while during summer periods, precipitation causes a decrease in daily water use. Graphs of heat functions (daily water demand deviations from its annual average value versus daily average temperature) show that above 78(degree)F, water demand increases linearly with average daily temperature.