History and context
In 1993, the Ontario Ministry of the EnvironmentRefers to the conditions in which an organism lives and survives or the conditions in which an organism resides. These conditions can be described as aspects of a “physical”, “social” or an “economic” environment, depending on the perspective perceived by the observer. (OMOE) and Ontario Ministry of Natural Resources (OMNR) released three policy documents focusing on integrating water resources management and urban planning:
- Water Management on a Watershed Basis: Implementing an Ecosystems Approach
- Subwatershed Planning
- Integrating Water Management Objectives into Municipal Planning Documents
These documents heralded a new approach to water management in Ontario. They emphasized the need for an increased focus on protecting the natural environmentRefers to the conditions in which an organism lives and survives or the conditions in which an organism resides. These conditions can be described as aspects of a “physical”, “social” or an “economic” environment, depending on the perspective perceived by the observer. and the need for stormwater management practices to pay more attention to water quality and environmental concerns, in addition to addressing traditional water quantity concerns.
In 1994, the OMOE released two practitioners guides to stormwater management planning:
- Stormwater Quality Best Management PracticesState of the art methods or techniques used to manage the quantity and improve the quality of wet weather flow. BMPs include Source, Conveyance and End-Of-Pipe Controls.
- Stormwater Management Practices Planning and Design (SMPPD) Manual
The OMOE SMPPD manual was intended to introduce practitioners to a broad range of stormwater management facilities designed to not only offset the effects of hydrologic changes of urban development on streams and rivers, but also address water quality and erosion impacts. The SMPPD manual also provided detailed guidance on how to design and build multi-purpose facilities and included sections on operations and maintenance and environmental monitoring requirements.
In 2003, OMOE released a new Stormwater Management Planning and Design Manual, which significantly updated and expanded on the 1994 version. The 2003 manual:
- provided an overview of the impacts of urbanizationThe changing of land cover and land uses from rural to urban; the growth of urban settlements. on the hydrologic cycleThe circulation of water from the atmosphere to the earth and back, through precipitation, runoff, infiltration, groundwater flow and evapotranspiration. and stream ecosystems
- addressed the evolution of the watershed planning process and its implications for the design process
- incorporated water quantity, erosion controlIncludes the protection of soil from dislocation by water, wind or other agents., water quality protection, and water balanceThe accounting of inflow and outflow of water in a system according to the components of the hydrologic cycle. principles into the selection and design of stormwater management practices (SWMPs)
- documented the performance of monitored SWMPs
- incorporated design considerations for SWMPs in cold climates
- provided information on new “state of the art” SWMPs
- addressed infill projects
- updated operations and maintenance requirements
- provided design examples for SWMPs
- updated material related to planting strategies and the function of plant materials in SWMP design
- provided examples of retrofitting SWMPs
- outlined integrated planning for stormwater management