Taking up The Challenge of CSO Monitoring: The City of Winnipeg Experience in Setting up an Ambitious Program

摘要

The City of Winnipeg Water and Waste Department initiated a Combined SewerOverflow (CSO) Outfall Monitoring Program with the installation of fifteen full scale pilotmonitoring sites between June 2009 and April 2010. The overall goal of the CSO MonitoringProgram is to develop a permanent monitoring system to accurately detect and quantify CSOevents. The system is also being provisioned to enable future real-time reporting of overflowevents.During the project’s two pilot phases, monitoring sites were instrumented with a combination offlowmeters, level meters, and inclinometers. Data analysis from these first installationsdetermined the most efficient ways to monitor CSOs. Different monitoring strategies weredeveloped and evaluated as part of a cost-benefit analysis for future site instrumentation. Basedon this analysis, the recommendation for the ongoing monitoring program was to primarily relyon a combination of level meters and inclinometers. These have proven to be reliable instrumentsand will provide redundancy in detecting overflows. It was also recommended to use a calibratedhydraulic model to estimate overflow volume. A model can provide sufficient accuracy forreporting purposes and is an interesting and cost-effective alternative when compared to the useof flowmeters. Further, experience gained from the pilot phases has shown that hydraulicconditions were not, for the most part, conducive to accurate and reliable flow gauging. Using areal-time model application can be a reliable tool and has the added advantage of offering manyother benefits to the City’s operation and planning functions.Status of Completion: Phases 1 and 2 of the project are complete with 15 sites instrumented andoperational. Design for the installation of ten additional sites (Phase 3) is currently underway.Commissioning of these sites and the development of an online data management, real timemodel, and reporting application is due at the end of 2012.