Event Detection Performance Study for the Development of a Contamination Warning System at the Philadelphia Water Department

摘要

As part of an EPA funded Contamination Warning System (CWS) Pilot Project, the PhiladelphiarnWater Department (PWD) maintains and receives data from over thirty different on-line waterrnquality monitoring (OWQM) stations throughout the city. Each of these stations collects data forrna minimum of eight discrete water quality parameters on two-minute intervals. Collecting thisrndata presents the need for an OWQM Event Detection System (EDS), which is an integral part ofrnthe CWS Pilot Project.rnThe goal of this study was to evaluate different EDS technologies throughout the waterrndistribution system. Two EDS’s were evaluated at specific monitoring stations with differentrnhydraulic profiles. These profiles included a pumping station, a reservoir influent and effluent,rnand multiple distribution locations. The specific objectives for this evaluation included:rn1. Minimizing the number of false alarms per week without omitting true alarms.rn2. Maximizing the system run time while minimizing the system malfunction and downrntime.rn3. Minimizing the time consumed working with the system while maximizing therninformation gained for investigation purposes. This includes decreasing calibration andrnsystem set up time, minimizing the time spent investigating alarms, and optimizing arngraphical user interface.rnThis paper will be focused on objectives one and three and will discuss the implementation,rninvestigation process, user interface, and algorithms behind both of these systems.