Hydraulic Calibration of a Water Distribution System Model

The Water Sector Research and Development Working Group has stated that water utilities would benefit from a clearer and more consistent understanding of their system flow dynamics. Understanding flow dynamics is important to interpreting water quality measurements and to inform basic operational decision making regarding the distribution system. Because these models will be used in decisions that involve significant investment and potential impact to the community, it is important that the model be an accurate representation of the actual conditions in the system. However, creating a hydraulic model of a water distribution system of any size comes with many difficulties, as many engineers can attest. Modeling smaller systems, such as the one in this study, is simpler from an engineering perspective but the challenge comes from the amount and quality of the information necessary to produce accurate results. For this model calibration we overcame issues such as collection of boundary condition data without a SCADA system, a 40% water loss due to system leaks and lack of system geometry data such as tank stage/storage curves, hydrant elevations, and valve closures. This study examines the use of data from hydraulic testing, especially C-factor and fire flow tests, and other collection methods to gather information about the system and calibrate a model for a small utility. Calibration was performed using the PIPE2010 program by KYPIPE, LLC.