Difference between revisions of "Site considerations"

From LID SWM Planning and Design Guide
Jump to navigation Jump to search
m
m
Line 3: Line 3:


|-
|-
!LID Stormwater Management Practice
!Installations 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
!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>
!Space % <ref>Percent of open pervious land on the site that is required for the LID practice</ref>
!Space % <ref>Percent of open pervious land on the site that is required for the LID practice</ref>
!Slope % <ref>Slope at the LID practice location</ref>
!Slope % <ref>Slope at the LID practice location</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>
!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 <ref>Separated from the seasonally high water table or top of bedrock elevation</ref>
!Water table <ref>Separated from the seasonally high water table or top of bedrock elevation</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 Barrel'''
|'''Rain Barrel'''

Revision as of 15:24, 31 January 2019

Installations 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 [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
Stormwater planters 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 (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
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