COMPREHENSIVE STORMWATER MANAGEMENT MASTER PLAN - PROJECT DESCRIPTION

Civica was retained in 2018 to undertake a Comprehensive Stormwater Management Master Plan (CSWM-MP) under both TRCA and LSRCA guidelines. This master plan is being prepared in accordance with the Municipal Class Environmental Assessment Phases 1 and 2. Civica is the lead coordinator in a multi-disciplinary team to accurately assess the characterization of the study area based on hydrology, geomorphology, groundwater resources, and natural heritage. This project includes dividing the study area into management units and developing existing and future conditions models to evaluate SWM controls. The model includes single-event and continuous simulations to achieve stormwater quality, quantity, water balance, and erosion requirements for the respective conservation authority. Following the Municipal EA process, a problem statement will be provided to describe the deficiencies of the existing SWM system and its impact on the natural environment. An implementation plan will then be developed to clearly identify recommendations for existing SWM facilities (i.e., SWM pond retrofits) and mitigation for the impact of future development (i.e., LIDs). This project also includes storing the Township’s SWM inventory into a database and planning for future inspections and maintenance.

Civica conducted topographic surveys and component inspections for 10 SWM facilities owned and operated by the Township. It was anticipated that some of the background information for some of these SWM facilities would be incomplete. The goal of this project was to obtain missing information related to the design of the pond (i.e., permanent pool elevations, active storage volume, etc.) which would be used to determine the storage-discharge relationship and aid in the development of a hydrologic model of the Township. As a value-added component, condition assessments were also performed for each of the ten facilities to locate, assess and evaluate the condition of all the components at the facility.All components in the facility were inspected which included photos, condition assessment, and georeferencing of all components. Inspected components included but were not limited to access roads, inlets & outlets, emergency spillways, and the general condition and function of the overall facility.