Difference between revisions of "Site considerations"

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Line 33: Line 33:
|'''[[Bioretention]]'''
|'''[[Bioretention]]'''
|1 (infiltrating); Not a constraint (non-infiltrating)
|1 (infiltrating); Not a constraint (non-infiltrating)
|5:1 to 15:1||[[Underdrain]] recommended<br>if < 15 mm/hr||1 to 2||5 to 10||0 to 2||No (infiltrating); Yes (non-infiltrating)||4m- Building Foundation<br>Underground Utilities, Trees,<br>Drinking Water Wellhead<br>Protection Areas||No (infiltrating); Yes (non-infiltrating)||2 yr (infiltrating); None (non-infiltrating)
|5:1 to 15:1||Decompaction and [[Underdrain]] recommended<br>if < 15 mm/hr||1 to 2||5 to 10||0 to 2||No (infiltrating); Yes (non-infiltrating)||4m- Building Foundation<br>Underground Utilities, Trees,<br>Drinking Water Wellhead<br>Protection Areas||No (infiltrating); Yes (non-infiltrating)||2 yr (infiltrating); None (non-infiltrating)
|-
|-
|'''[[Stormwater planters]]'''
|'''[[Stormwater planters]]'''
Line 41: Line 41:
|'''[[Vegetated filter strips]]'''
|'''[[Vegetated filter strips]]'''
|Not a constraint
|Not a constraint
|4:1 or less||Decompact if < 15 mm/hr||0 to 1||15 to 20||1 to 5||No||None||Yes||None
|4:1 or less||Decompaction if < 15 mm/hr||0 to 1||15 to 20||1 to 5||No||None||Yes||None
|-
|-
|'''[[Permeable pavements]]'''
|'''[[Permeable pavements]]'''
Line 49: Line 49:
|'''[[Enhanced swales]] (featuring check dams)'''
|'''[[Enhanced swales]] (featuring check dams)'''
|1  
|1  
|5:1 to 10:1||Decompact if < 15 mm/hr||1 to 3||5 to 15||0.5 to 6||No||4m- Building Foundation<br>Underground Utilities||No||2 Yr
|5:1 to 10:1||Decompaction if < 15 mm/hr||1 to 3||5 to 15||0.5 to 6||No||4m- Building Foundation<br>Underground Utilities||No||2 Yr
|-
|-
|'''[[Bioswales]] (Dry swales)'''
|'''[[Bioswales]] (Dry swales)'''
|1 (infiltrating); Not applicable (non-infiltrating)
|1 (infiltrating); Not applicable (non-infiltrating)
|5:1 to 15:1||Underdrain recommended <br> if < 15 mm/hr||1 to 3||5 to 10||0.5 to 6||No (infiltrating); Yes (non-infiltrating)||4m (3m if impermeable liner<br>is used) Building foundation,<br> Underground utilities,<br> Drinking Water Wellhead Protection Areas||No (infiltrating); Yes (non-infiltrating)||2 Yr (infiltrating); None (non-infiltrating)
|5:1 to 15:1||Decompaction and [[Underdrain]] recommended <br> if < 15 mm/hr||1 to 3||5 to 10||0.5 to 6||No (infiltrating); Yes (non-infiltrating)||4m (3m if impermeable liner<br>is used) Building foundation,<br> Underground utilities,<br> Drinking Water Wellhead Protection Areas||No (infiltrating); Yes (non-infiltrating)||2 Yr (infiltrating); None (non-infiltrating)
|-
|-
|'''[[Exfiltration trenches]]'''
|'''[[Exfiltration trenches]]'''

Revision as of 18:32, 10 March 2022

Installation type Depth to high water or bedrock (m)[1] 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 a constraint Not applicable Not a constraint 1 0 NA Yes None Yes None
Cisterns Not a constraint Not applicable Not a constraint 0 0 0 Yes None Yes None
Roof downspout disconnection Not a constraint 4:1 or less Decompact 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 a constraint (non-infiltrating) 5:1 to 15:1 Decompaction and 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 a constraint 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 a constraint 4:1 or less Decompaction 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) 0 to 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 Decompaction if < 15 mm/hr 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 Decompaction and 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