To comply with the recommendations of the Manitoba Clean Environment Commission regarding the instrumentation of CSO outfalls, the City of Winnipeg is implementing a city-wide comprehensive centralized CSO Outfall Monitoring Program. This program combines permanent meter installations with real-time modeling in order to collect and report on the frequency, duration and volume of overflow conditions for all 79 overflow structures of the combined sewer network. The data will provide the City with a better understanding of the existing overflow conditions and inputs in order to prioritize future works for CSO control.
As the prime consultant, Tetra Tech CSO led the preparation and implementation of the Monitoring Program. One of the key program components is the development of a CSO detection and reporting tool based on real-time modeling and automated data analysis to meet the City’s objective of turning the monitoring data into actionable information. The tool provides real-time information about CSO events as well as periodic reports allowing the City to meet its regulatory reporting obligations as well as hydraulic and system performance analysis. It uses the City’s InfoWorks model for the real-time modeling application to provide automatic comparisons of measurement data with model results to trigger alarms and to calculate critical information on CSO conditions. Furthermore, the use of the real-time model to represent CSO conditions at certain secondary outfalls yielded significant cost savings by avoiding the need for permanent overflow monitoring equipment at these sites.
To develop and implement the real-time reporting tool, Tetra Tech CSO used a collaborative approach where regular communication and status meetings ensured that the indicators and reports generated by the tool were aligned with the City’s operational needs and that the tool could be used and maintained by City staff autonomously.
The real-time data analysis and reporting tool relied on the integration of robust commercially available technology, including a time series storage, calculation and analysis module (WISKI, commercialised by Kisters), an external model simulation controller (Csoft Pilot, commercialised by Tetra Tech CSO), and a hydrologic and hydraulic collection system model (InfoWorks, commercialised by Innovyze). This design allows flexible configuration of data validation and indicator calculation algorithms directly within the time series module user interface for both real-time application and offline analysis. The reporting tool can also be efficiently scaled to include other aspects of the City of Winnipeg collection system’s operational and environmental performances.
Demonstration of cost savings in the CSO monitoring program; maximize the use of data and investment; scalable.