Difference between revisions of "Site considerations"

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!Applicable in pollution hotspots <ref>Suitable in pollution hot spots or runoff source areas where land uses or activities have the potential to generate highly contaminated runoff</ref>
!Applicable in pollution hotspots <ref>Suitable in pollution hot spots or runoff source areas where land uses or activities have the potential to generate highly contaminated runoff</ref>
!Set backs
!Set backs
!Water table separation<ref>Must have adequate separation from the seasonally high water table or top of bedrock elevation</ref>
!Karst<ref>Suitability in areas of karst geologic formations</ref>
!Wellhead protection area<ref>|Time-of-travel within wellhead protection areas</ref>
!Wellhead protection area<ref>|Time-of-travel within wellhead protection areas</ref>
|-
|-
|'''[[Rain barrels|Rain Barrel]]'''
|'''[[Rain barrels|Rain Barrel]]'''
|Not applicable
|Not applicable
||5 to 50 m<sup>2</sup>||Not applicable||1||0||NA||Yes||None||No||None
||5 to 50 m<sup>2</sup>||Not applicable||1||0||NA||Yes||None||Yes||None
|-
|-
|'''[[rainwater harvesting|Cistern]]'''
|'''[[rainwater harvesting|Cistern]]'''
|Not applicable
|Not applicable
|1:1||Not applicable||0||0||0||Yes||None||No||None
|1:1||Not applicable||0||0||0||Yes||None||Yes||None
|-
|-
|'''[[Downspout disconnection|Roof downspout disconnection]]'''
|'''[[Downspout disconnection|Roof downspout disconnection]]'''
|Not applicable
|Not applicable
|5 to 100 m<sup>2</sup>||Amend if < 15 mm/hr||0.5||5 to 20||1 to 5||Yes||Building Foundation||No||None
|5 to 100 m<sup>2</sup>||Amend if < 15 mm/hr||0.5||5 to 20||1 to 5||Yes||Building Foundation||Yes||None
|-
|-
|'''Soakaway, infiltration trench or chamber'''
|'''Soakaway, infiltration trench or chamber'''
|1
|1
|5:1 to 20:1||Not a constraint||1 to 2||0 to 1||<15 %||No||4m- Building Foundation<br>Underground Utilities, Trees,<br>Drinking Water Wellhead<br>Protection Areas||Yes||2 yr
|5:1 to 20:1||Not a constraint||1 to 2||0 to 1||<15 %||No||4m- Building Foundation<br>Underground Utilities, Trees,<br>Drinking Water Wellhead<br>Protection Areas||No||2 yr
|-
|-
|'''[[Bioretention]]'''
|'''[[Bioretention]]'''
|1
|1
|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||Yes||2 yr (infiltrating); None (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)
|-
|-
|'''[[Stormwater planters]]'''
|'''[[Stormwater planters]]'''
|Not applicable
|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||2 Yr (infiltrating); None (non-infiltrating)
|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 strip]]'''
|'''[[Vegetated filter strip]]'''
|1
|Not applicable
|5:1||Amend if < 15 mm/hr||0 to 1||15 to 20||1 to 5||No||None||No||None
|5:1||Amend if < 15 mm/hr||0 to 1||15 to 20||1 to 5||No||None||Yes||None
|-
|-
|'''[[Permeable pavement]]'''
|'''[[Permeable pavement]]'''
|1
|1
|1:1 to 1.2:1||Underdrain recommended <br> if < 15 mm/hr||0.5 to 1||0||1 to 5||No (infiltrating); Yes (non-infiltrating)||4m-Underground Utilities<br>Drinking Water Wellhead<br>Protection Areas||Yes||2 Yr (infiltrating); None (non-infiltrating)
|1:1 to 1.2:1||Underdrain recommended <br> if < 15 mm/hr||0.5 to 1||0||1 to 5||No (infiltrating); Yes (non-infiltrating)||4m-Underground Utilities<br>Drinking Water Wellhead<br>Protection Areas||No (infiltrating); Yes (non-infiltrating)||2 Yr (infiltrating); None (non-infiltrating)
|-
|-
|'''[[Enhanced grass swale]](has checkdams)'''
|'''[[Enhanced grass swale]](has checkdams)'''
|1
|Not applicable
|5:1 to 10:1||Not applicable||1 to 3||5 to 15||0.5 to 6||No||4m- Building Foundation<br>Underground Utilities||Yes||None
|5:1 to 10:1||Not applicable||1 to 3||5 to 15||0.5 to 6||No||4m- Building Foundation<br>Underground Utilities||Yes||None
|-
|-
|'''[[Dry swale]] (Bioswale)'''
|'''[[Dry swale]] (Bioswale)'''
|1
|1
|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||Yes||2 Yr (infiltrating); None (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)
|-
|-
|'''[[Perforated pipe system]]'''
|'''[[Perforated pipe system]]'''
|1
|1
|5:1 to 10:1||Not a constraint||1 to 3||0||< 15%||No||4m- Building Foundation<br>Underground Utilities, Trees,<br>Drinking Water Wellhead<br>Protection Areas||Yes||2 Yr
|5:1 to 10:1||Not a constraint||1 to 3||0||< 15%||No||4m- Building Foundation<br>Underground Utilities, Trees,<br>Drinking Water Wellhead<br>Protection Areas||No||2 Yr
|}
|}

Revision as of 20:11, 9 April 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 Karst[7] Wellhead protection area[8]
Rain Barrel Not applicable 5 to 50 m2 Not applicable 1 0 NA Yes None Yes None
Cistern Not applicable 1:1 Not applicable 0 0 0 Yes None Yes 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 Yes 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
No 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 (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 strip Not applicable 5:1 Amend if < 15 mm/hr 0 to 1 15 to 20 1 to 5 No None Yes None
Permeable pavement 1 1:1 to 1.2:1 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 grass swale(has checkdams) Not applicable 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 (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)
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
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. |Time-of-travel within wellhead protection areas