Difference between revisions of "Site considerations"

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!Installation type
 
!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 impervious drainage area to permeable facility footprint area
+
!Typical ratio of impervious <br>drainage area to permeable <br>facility footprint area
 
!Native soil infiltration rate (mm/hr)<ref>Infiltration rate estimates based on measurements of hydraulic conductivity under field saturated conditions at the proposed location and depth of the practice</ref>
 
!Native soil infiltration rate (mm/hr)<ref>Infiltration rate estimates based on measurements of hydraulic conductivity under field saturated conditions at the proposed location and depth of the practice</ref>
 
!Head (m)<ref>Vertical distance between the inlet and outlet of the LID practice</ref>
 
!Head (m)<ref>Vertical distance between the inlet and outlet of the LID practice</ref>

Revision as of 18:12, 10 March 2022

Installation type Depth to high water or bedrock (m)[1] Typical ratio of impervious
drainage area to permeable
facility footprint area
Native soil infiltration rate (mm/hr)[2] Head (m)[3] Space % [4] Slope % [5] Applicable in pollution hotspots [6] Set backs Karst[7] Wellhead protection area[8]
Rain barrels Not applicable Not applicable Not applicable 1 0 NA Yes None Yes None
Cisterns Not applicable Not applicable Not applicable 0 0 0 Yes None Yes None
Roof downspout disconnection Not applicable 4:1 or less Amend if < 15 mm/hr 0.5 5 to 20 1 to 5 Yes Building Foundation Yes None
Infiltration trenches or Infiltration chambers 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
No 2 yr
Bioretention 1 (infiltrating); Not applicable (non-infiltrating) 5:1 to 15:1 Underdrain recommended
if < 15 mm/hr
1 to 2 5 to 10 0 to 2 No (infiltrating); Yes (non-infiltrating) 4m- Building Foundation
Underground Utilities, Trees,
Drinking Water Wellhead
Protection Areas
No (infiltrating); Yes (non-infiltrating) 2 yr (infiltrating); None (non-infiltrating)
Stormwater planters Not applicable 5:1 Not a constraint 1 to 2 2 to 5 0 to 2 No (infiltrating); Yes (non-infiltrating) Building Foundation, Trees No (infiltrating); Yes (non-infiltrating) 2 Yr (infiltrating); None (non-infiltrating)
Vegetated filter strips Not applicable 5:1 Amend if < 15 mm/hr 0 to 1 15 to 20 1 to 5 No None Yes None
Permeable pavements 1 (infiltrating); Not applicable (non-infiltrating) 1:1 Underdrain recommended
if < 15 mm/hr
0.5 to 1 0 1 to 5 No (infiltrating); Yes (non-infiltrating) 4m-Underground Utilities
Drinking Water Wellhead
Protection Areas
No (infiltrating); Yes (non-infiltrating) 2 Yr (infiltrating); None (non-infiltrating)
Enhanced swales (featuring check dams) 1 5:1 to 10:1 Not applicable 1 to 3 5 to 15 0.5 to 6 No 4m- Building Foundation
Underground Utilities
No 2 Yr
Bioswales (Dry swales) 1 (infiltrating); Not applicable (non-infiltrating) 5:1 to 15:1 Underdrain recommended
if < 15 mm/hr
1 to 3 5 to 10 0.5 to 6 No (infiltrating); Yes (non-infiltrating) 4m (3m if impermeable liner
is used) Building foundation,
Underground utilities,
Drinking Water Wellhead Protection Areas
No (infiltrating); Yes (non-infiltrating) 2 Yr (infiltrating); None (non-infiltrating)
Exfiltration trenches 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
No 2 Yr
Stormwater tree trenches 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,
Drinking Water Wellhead
Protection Areas
No 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. Suitability in areas of karst geologic formations
  8. | Drinking Water Source Protection wellhead protection area time of travel