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→Literature Review
==Literature Review==
==Literature Review==
Below are examples of where LID practices with quantity control components have been used for achieving flood control.
===Example 1: Costco Distribution Centre===
===Example 1: Costco Distribution Centre===
#Underdrain is undersized to increase detention times during flood events. Orifice controls are installed in the downstream sewer to control release rates.
#Underdrain is undersized to increase detention times during flood events. Orifice controls are installed in the downstream sewer to control release rates.
#An automated irrigation system for the playing field and vegetated areas draws stored water from the rainwater cistern to increase capacity during storm events. Outside of the growing season, rainwater from the cistern drains directly to a dry pond which provides temporary storage and release.
#An automated irrigation system for the playing field and vegetated areas draws stored water from the rainwater cistern to increase capacity during storm events. Outside of the growing season, rainwater from the cistern drains directly to a dry pond which provides temporary storage and release.
===Example 5: Wychwood Subdivision in Brampton===
The Wychwood subdivision is located on Walnut Road in Brampton. The 70 lot residential development covers an area of approximately 5 hectares and has an overall imperviousness of 47%.
'''Stormwater Management Criteria'''
*Quantity Control – reduce 2 to 100 year flows to pre-development levels
*Quality Control – 80% TSS Removal;
*Water Balance – match pre-development infiltration volumes
*Stream Erosion control: Manage, detain or re-use all rainfall up to 15 mm over the entire site
'''Stormwater Management Strategy'''
#East portion of the site controls minor and major flows through a long bioswale adjacent to the rail line. Driveways are permeable and added top soil helps improve retention of runoff from roofs, which drain to the lawns.
#West portion of the site controls runoff through infiltration swales with orifice controls on underdrains and lot level rain gardens
#All runoff is controlled by LID practices (no dry/wet ponds or underground tanks)
'''Monitoring and Modelling Results'''
*There was 125 rain events monitored and 41 composite samples collected. Modelling was used to determine inflow volumes/rates and water equality loading.
*Low impact development features provide 77 percent volume reductions for events up to 25mm
*TSS load reductions were reduced by 84%
*Event greater than 30 mm showed peak flow reductions of 74%, with a total volume reduction of 59%
*Modelling pre and post development peak flow rates indicated that peak flow targets were met for the 2 to 50 year storms but post development peak flows were *10% greater than pre development peak flows for the 100 year storm.
==Data Analysis/Modelling==
==Data Analysis/Modelling==