The Region of Peel Sanitary Sewer Model - An Integrated Geospatial Approach to Hydraulic Modeling of Large Sanitary Sewer Systems Public agencies are moving towards full-cost accounting and developing proactive rehabilitation and replacement methodologies for the maintenance of their infrastructure assets. Hydraulic modeling can provide a key analytical tool in the management of sanitary sewer collection systems from which agencies can assess the performance of their infrastructure, identify potential problems, plan cost-effective solutions, and mitigate risk. Hydraulic models have historically been very costly and difficult to maintain since they rely on a large amount of information from a variety of sources. The Region of Peel was searching for improved ways to analyze and proactively plan its sanitary sewer infrastructure. Peel is a fast-growing upper tier regional municipality located just west of Toronto, Canada. It has a current population of approximately 1.0 million people, which is projected to grow to 1.4 million people by 2031. Due to the large inventory of sanitary infrastructure and the projected high rate of expansion due to growth, Peel decided that a new, more easily maintainable sanitary sewer model would be required. Such a model would need to integrate with Peel's Geomedia GIS, Hansen IMS and AquaPeel water billing systems to provide a real-time data warehouse for hydraulic modeling, thus eliminating ongoing data collection efforts. To meet this challenge, Peel retained Earth Tech (Earth Tech Incorporated, 105 Commerce Valley Drive West, 7th Floor, Markham, Ontario L3T 7W3 Canada) to develop an integrated hydraulic modeling system for steady-state (single time step) sanitary network analysis and asset management. The model was required to examine potential problems and solutions in the sanitary distribution system, identify surplus capacity for infilling purposes and confirm proposed infrastructure requirements to address Peel's growth-related needs. Due to the large inventory of sanitary sewer infrastructure and the projected high rate of system expansion, the new sanitary sewer model had to be highly reliable, easily maintainable and readily expandable. The Peel sanitary sewer model was developed in five (5) stages: software selection, data collection, data validation, model development and model integration/training. Based on a comprehensive review of hydraulic sanitary sewer models, Earth Tech selected H2OMAP Sewer for this project. H2OMAP Sewer's selection was based on various criteria including: steady state modeling capabilities, GIS integration, data management features, cost (initial and annual maintenance), run times, graphics and user friendliness. Data for the model was provided digitally from Peel's existing GIS, IMS and water billing systems. An Automated Spatial Demand Allocation (ASDA) application, developed by Earth Tech, was utilized to accurately allocate demands extracted from Peel's Corporate Information Systems. Using the above noted data and Regional Design Criteria; a number of modeling scenarios were developed to analyze Peel's current and future (proposed) sanitary sewer system. The model was calibrated using flow monitoring records provided by the Region of Peel. The final H2OMAP Sewer model represented a 41,500 ha (102,550 Ac.) service area consisting of: 36,100 manholes, 37,000 pipes (approx. 2,730 km of sewer), 40 Lift Stations and 2 Wastewater Treatment Plants. Each simulation required under five (5) minutes to complete. The figure below illustrates the H2OMAP Sewer User Interface. Following Earth Tech's assessment of the sanitary sewer system, the model was integrated with the Region of Peel's Corporate Information Systems by developing several customized integration routines and software protocols (Oracle stored procedures and snapshots) to maintain relational integrity at the database level. Users can use the ODBC functions that are provided in H2OMAP Sewer to connect to these external data sources, keep the model up-to-date and share analytical results. Today, Peel staff can seamlessly update the entire sanitary sewer model with a few keystrokes on their desktop computer. This has reduced Peel's dependency on outsourcing for model updates and additional data collection; thereby, increasing efficiency in business and maintenance operations. Region of Peel (Canada) H2OMAP Sewer Model (Click to enlarge the picture)