TEmporal Scale SIgmoid Curve (TESIC): A tool to characterize short-term demand variability at water supply systems

Abstract

[EN] Water demand is the main random factor that conditions flow variability across water supply systems. Water demand measurements or pseudomeasurements (i.e. estimations based on historical data) are associated with a time interval (sampling rate), which affects the variability of water demands. Considering a long time interval implies losing information about water consumption within that temporal window. The variance (i.e. quantification of variability) computed from demand records is thus only “apparent”, because the variability within the time interval is averaged and lost (i.e. “missed”). The relationship between missed and apparent variability can be assessed through the so-called TEmporal scale SIgmoid Curve (TESIC), which is here presented as a tool to characterize short-term demand variability. TESIC is used in this work to compute demand uncertainty for a given time resolution level and to estimate peak demands for different temporal resolutions in a realistic water supply case study. These applications show that TESIC provides a conceptual framework to explain and quantify the temporal resolution effect in hydraulic modelling applications.