Changes

#Final design required both LIDs to reduce the overall runoff volumes, but also sub-surface storage chambers to provide quantity control for rare storm events up to the 100-year design storm. Due to large area required for truck parking, limited opportunities for more landscaping to promote [[evapotranspiration]], runoff volumes increased beyond ability of LIDs to negate the need for quantity control.

#Final design required both LIDs to reduce the overall runoff volumes, but also sub-surface storage chambers to provide quantity control for rare storm events up to the 100-year design storm. Due to large area required for truck parking, limited opportunities for more landscaping to promote [[evapotranspiration]], runoff volumes increased beyond ability of LIDs to negate the need for quantity control.

===Example 4. West Gormley, Town of Richmond Hill===

===Example 4. [https://sustainabletechnologies.ca/app/uploads/2020/12/SmartBlueRoofSTEPTechBrief_Dec2020.pdf Smart Blue Roof System]===

Residential development consisting of low and medium density land-use is implemented on the site. Average site imperviousness is approximately 60%;

[[Blue roofs]] are emerging as an innovative rooftop stormwater management solution that provides flood protection and drought resistance. Instead of quickly conveying stormwater away from a property, blue roof systems temporarily capture rainwater until it either evaporates from the rooftop or is sent to rainwater harvesting storage tanks. A Smart Blue Roof was piloted at the CVC head office in Mississauga.

'''Stormwater Management Criteria'''

'''Stormwater Management Criteria'''

*Quantity Control – Rouge River – match post development peak flow rates to pre-development;

*Quantity Control –

*Quality Control – 80% TSS Removal;

*Quality Control –  

*Water Balance –Match post development water budget to pre-development;

*Water Balance –

*Erosion Control – Southern portion of site discharging to a natural dry valley feature.  Feature and contributing drainage area consists of very sandy soil, producing no runoff until a greater than 25-year storm event.

*Erosion Control –

'''Stormwater Management Strategy'''

'''Stormwater Management Strategy'''

#Use a combination of increased topsoil depths, perforated storm sewers, stormwater management facility, and an [[infiltration]] facility to provide [[water quality|quality]], quantity, and reduce runoff volumes to match pre-development.

#

#Even with favorable soils and maximum use of infiltration techniques, site still requires quantity control storage for large storm events.

#

 

'''Stormwater Management Criteria'''

'''Stormwater Management Criteria'''

*Quantity Control – not requirement as drains to Lower Humber River

*Quantity Control –

*Quality Control – 80% TSS Removal

*Quality Control –

*Water balance/Erosion Control – Retention of 5 mm event on-site

*Water balance/Erosion Control –

'''Stormwater Strategy'''

'''Stormwater Strategy'''

#Large portion of the roof proposed as green roof and cistern proposed in underground parking to capture remaining volume to meet 5 mm target.  Water to be used for irrigation and carwash stations.

#

#Quality target achieved as majority of site is ‘clean’ roof water or directed to pervious area. Underground storage tank provided to satisfy municipal release rates to receiving storm sewer system.

#

#Final design required both LIDs to reduce the overall runoff volumes, but also sub-surface storage chambers to provide quantity control to meet municipal requirements.

#

#Due to underground parking limited opportunities for infiltration LIDs but used [[green roof]] to promote [[evapotranspiration]], and [[Rainwater Harvesting & Cisterns: Life Cycle Costs|cistern]] to reduce runoff volumes.

#

==Data Analysis/Modelling==

==Data Analysis/Modelling==