Changes

An area, for example that contains a high density of roads and industrial areas that require large amounts of de-icing [[salt| road salt]] in the winter and experiences heavy traffic daily, make it a significant source of sodium, chloride, petroleum based hydrocarbons and [[heavy metals]]. On the other hand a source area such as a roof is only subject to atmospheric deposition of contaminants and isn't typically subjected to vehicular traffic, sand, [[salt]] nor other de-icing agents. As a result, roof runoff typically contains significantly lower levels of [[heavy metals]], petroleum hydrocarbons, salt.

An area, for example that contains a high density of roads and industrial areas that require large amounts of de-icing [[salt| road salt]] in the winter and experiences heavy traffic daily, make it a significant source of sodium, chloride, petroleum based hydrocarbons and [[heavy metals]]. On the other hand a source area such as a roof is only subject to atmospheric deposition of contaminants and isn't typically subjected to vehicular traffic, sand, [[salt]] nor other de-icing agents. As a result, roof runoff typically contains significantly lower levels of [[heavy metals]], petroleum hydrocarbons, salt.

Certain source areas known as "pollution hot spots" have a higher chance to create contaminated surface level runoff due to given activities occurring and associated contaminant types present on site (e.g., vehicle fueling stations, landfills, certain agricultural practices, manufacturing and construction sites). As a result of this different runoff contamination levels also limit the types of treatment opportunities and practices that can be implemented in varying source water areas. It is important that stormwater management plans be developed with consideration of the different types of runoff source areas that will be present, and recognition of source

Certain source areas known as "pollution hot spots" have a higher chance to create contaminated surface level runoff due to given activities occurring and associated contaminant types present on site (e.g., vehicle fueling stations, landfills, certain agricultural practices, manufacturing and construction sites). It is important that stormwater management plans be developed with consideration of the different types of runoff source areas that will be present, and recognition of source areas with low to moderate contamination potential that represent opportunities for [[Rainwater Harvesting| rainwater harvesting]], [[permeable pavements]] and other stormwater infiltration practices. Furthermore, it is important to ensure that relatively clean runoff is not mixed with lesser quality runoff from surfaces that are subject to higher levels of contamination, rendering it less suitable for infiltration or harvesting.  

areas with low to moderate contamination potential that represent opportunities for [[Rainwater Harvesting| rainwater harvesting]], [[permeable pavements]] and other stormwater infiltration practices. Furthermore, it is important to ensure that relatively clean runoff is not mixed with lesser quality runoff from surfaces that are subject to higher levels of contamination, rendering it less suitable for infiltration or harvesting.  

A summary of stormwater source area types, associated runoff characteristics and stormwater BMP opportunities and pretreatment requirements is provided in the table below:

A summary of stormwater source area types, associated runoff characteristics and stormwater BMP opportunities and pretreatment requirements is provided in the table below: