Effect of reservoir elevation on energy consumption in water distribution systems

As precipitation and drought patterns alter in the future, it is unclear what the reservoir water elevations will be in various water sources. A modeling study performed in the present study, consisting of altering the reservoir water level and recording the resultant energy consumption for fifteen existing water distribution systems resulted in the conclusion that, for most systems, rising reservoir water levels will linearly decrease energy consumption. This is due to less static suction head for the pump to overcome and, therefore, less pumping time and more ‘off’ time. The sensitivity of energy consumption to reservoir water level head varied between systems, however, primarily due to the pipe diameters, and therefore water velocity values, relative to the system conditions. One exception was a system with the reservoir water elevation above the storage tank. This was due to excessive demand emptying the storage tanks, thereby resulting in less water level head.