Difference between revisions of "Site considerations"

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|5:1 to 15:1||Underdrain required<br>if < 15 mm/hr||1 to 2||5 to 10||0 to 2||No||4m- Building Foundation<br>Underground Utilities, Trees,<br>Drinking Water Wellhead<br>Protection Areas||1 m||2 yr
 
|5:1 to 15:1||Underdrain required<br>if < 15 mm/hr||1 to 2||5 to 10||0 to 2||No||4m- Building Foundation<br>Underground Utilities, Trees,<br>Drinking Water Wellhead<br>Protection Areas||1 m||2 yr
 
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|-
!style="background: #FFFDF5; color: black"|Biofilter (Filtration only Bioretention Design)
+
|Biofilter (Filtration only Bioretention Design)
!Not applicable
+
|Not applicable
!|5:1||Not applicable||1 to 2||2 to 5||0 to 2||Yes||Building Foundation, Trees||None||None
+
|5:1||Not applicable||1 to 2||2 to 5||0 to 2||Yes||Building Foundation, Trees||None||None
 
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|Vegetated Filter Strip
 
|Vegetated Filter Strip

Revision as of 15:17, 31 January 2019

LID Stormwater Management Practice Depth to High Water or Bedrock (m)[1] Typical Ratio of
Impervious Drainage Area
to Treatment Facility Area
Native Soil Infiltration Rate (mm/hr)[2] Head (m)[3] Space % [4] Slope % [5] Applicable in Pollution Hotspots [6] Set Backs Water Table [7] Wellhead Protection Area[8]
Rain Barrel Not applicable [5 to 50 m2] Not applicable 1 0 NA Yes None None None
Cistern Not applicable 1:1 Not applicable 0 0 0 Yes None None None
Roof Downspout Disconnection Not applicable [5 to 100 m2] Amend if < 15 mm/hr 0.5 5 to 20 1 to 5 Yes Building Foundation None None
Soakaway, Infiltration Trench or Chamber 1 5:1 to 20:1 Not a constraint 1 to 2 0 to 1 <15 % No 4m- Building Foundation
Underground Utilities, Trees,
Drinking Water Wellhead
Protection Areas
1 m 2 yr
Bioretention 1 5:1 to 15:1 Underdrain required
if < 15 mm/hr
1 to 2 5 to 10 0 to 2 No 4m- Building Foundation
Underground Utilities, Trees,
Drinking Water Wellhead
Protection Areas
1 m 2 yr
Biofilter (Filtration only Bioretention Design) Not applicable 5:1 Not applicable 1 to 2 2 to 5 0 to 2 Yes Building Foundation, Trees None None
Vegetated Filter Strip 1 5:1 Amend if < 15 mm/hr 0 to 1 15 to 20 1 to 5 No None None None
Permeable Pavement 1 1:1 to 1.2:1 Underdrain Required
if < 15 mm/hr
0.5 to 1 0 1 to 5 No 4m-Underground Utilities
Drinking Water Wellhead
Protection Areas
1 m 2 Yr
Enhanced Grass Swale 1 5:1 to 10:1 Not applicable 1 to 3 5 to 15 0.5 to 6 No 4m- Building Foundation
Underground Utilities
1 m None
Dry Swale (Bioswale) 1 5:1 to 15:1 Underdrain Required
if < 15 mm/hr
1 to 3 5 to 10 0.5 to 6 No 4m (3m if impermeable liner
is used)Building foundation,
Underground utilities, drinking
water wellhead protection areas
1 m 2 Yr
Perforated Pipe System 1 5:1 to 10:1 Not a constraint 1 to 3 0 < 15% No 4m- Building Foundation
Underground Utilities, Trees,
Drinking Water Wellhead
Protection Areas
1 m 2 Yr
  1. Minimum depth between the base of the facility and the elevation of the seasonally high water table or top of bedrock
  2. Infiltration rate estimates based on measurements of hydraulic conductivity under field saturated conditions at the proposed location and depth of the practice
  3. Vertical distance between the inlet and outlet of the LID practice
  4. Percent of open pervious land on the site that is required for the LID practice
  5. Slope at the LID practice location
  6. Suitable in pollution hot spots or runoff source areas where land uses or activities have the potential to generate highly contaminated runoff
  7. Separated from the seasonally high water table or top of bedrock elevation
  8. |Time-of-travel within wellhead protection areas