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Line 19: − |- − !style="background: darkcyan; color: white"|Simple downspout disconnection requires a minimum flow path length across the pervious area(at least 5 metres) <br>+ − and suitable soil conditions. If the flow path length is less <br> − than 5 metres and soils are hydrologic soil group (HSG) C or D, roof downspouts should be directed to another LID practice such as a rainwater harvesting system, soakaway, swale, bioretention area or perforated pipe system. − !Disconnected downspouts should discharge to a gradual slope that conveys runoff away from the building. The slope should be between 1% and 5%. Grading should discourage flow from reconnecting with adjacent impervious surfaces || || If the infiltration rate of soils in the pervious area is less than 15 mm/hr, they should be tilled to a depth of 300 mm and amended with compost to achieve an organic content in the range of 8 to 15% by weight or 30 to 40% by volume. || Downspout disconnection can be used where land uses or activities at ground-level have the potential to generate highly contaminated runoff as long as the roof runoff is kept separate from runoff from groundlevel impervious surfaces || || || For simple downspout disconnection the roof drainage area should not be greater than 100 square metres || || || || || || || ||
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!style="background: darkcyan; color: white"|Structural Requirements
!style="background: darkcyan; color: white"|Structural Requirements
!style="background: darkcyan; color: white"|Roof Slope
!style="background: darkcyan; color: white"|Roof Slope
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! Roof Downspout Disconnection
! Roof Downspout Disconnection
|Simple downspout disconnection requires a minimum flow path length |Disconnected downspouts should discharge to a gradual slope that conveys runoff away from the building. The slope should be between 1% and 5%. Grading should discourage flow from reconnecting with adjacent impervious surfaces || || If the infiltration rate of soils in the pervious area is less than 15 mm/hr, they should be tilled to a depth of 300 mm and amended with compost to achieve an organic content in the range of 8 to 15% by weight or 30 to 40% by volume. || Downspout disconnection can be used where land uses or activities at ground-level have the potential to generate highly contaminated runoff as long as the roof runoff is kept separate from runoff from groundlevel impervious surfaces || || || For simple downspout disconnection the roof drainage area should not be greater than 100 square metres || || || || || || || ||
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! Soakaways, Infiltration Trenches and Chambers
! Soakaways, Infiltration Trenches and Chambers