Difference between revisions of "Site considerations"

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!Installations type
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!Installation type
 
!Depth to high water or bedrock (m)<ref>Minimum depth between the base of the facility and the elevation of the seasonally high water table or top of bedrock</ref>
 
!Depth to high water or bedrock (m)<ref>Minimum depth between the base of the facility and the elevation of the seasonally high water table or top of bedrock</ref>
 
!Typical ratio of <br>Impervious drainage area<br> to Treatment Facility Area
 
!Typical ratio of <br>Impervious drainage area<br> to Treatment Facility Area

Revision as of 14:21, 13 February 2019

Installation type 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 separation[7] Wellhead protection area[8]
Rain Barrel Not applicable 5 to 50 m2 Not applicable 1 0 NA Yes None No None
Cistern Not applicable 1:1 Not applicable 0 0 0 Yes None No 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 No 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
Yes 2 yr
Bioretention 1 5:1 to 15:1 Underdrain recommended
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
Yes 2 yr
Stormwater planters Not applicable 5:1 Not applicable 1 to 2 2 to 5 0 to 2 Yes Building Foundation, Trees No None
Vegetated filter strip 1 5:1 Amend if < 15 mm/hr 0 to 1 15 to 20 1 to 5 No None No None
Permeable pavement 1 1:1 to 1.2:1 Underdrain recoomended
if < 15 mm/hr
0.5 to 1 0 1 to 5 No 4m-Underground Utilities
Drinking Water Wellhead
Protection Areas
Yes 2 Yr
Enhanced grass swale(has checkdams) 1 5:1 to 10:1 Not applicable 1 to 3 5 to 15 0.5 to 6 No 4m- Building Foundation
Underground Utilities
Yes None
Dry swale (Bioswale) 1 5:1 to 15:1 Underdrain recommended
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
Yes 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
Yes 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. Must have adequate separation from the seasonally high water table or top of bedrock elevation
  8. |Time-of-travel within wellhead protection areas