Talk:Enhanced Grass Swale Design Guide
Revision as of 19:18, 3 October 2017 by Muwaffaq Al-Awad (talk | contribs)
LID Practice | CANADA | United States | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Bioretention | CVC+TRCA (Factsheets-2010)[1] | Toronto- 2016 | LID-SWM Guide 2010[2] | New York State SWM Design Manual-2015 | Massachusets SW BMP-2013 | District of Columbia-SWM Guidebook-2010 | San Diego LID Handbook-2014 | Alabama LID Handbook-2013 | W. Virginia-SWM design guidance manual-2012 | Tennessee-LID Development-SWM 2016 | Texas-LID Technical Guidance Manual-2013 | Oregon SWM Manual-2014 | Oregon State Univ. Fact Sheets-2011 | |
Swale length between culverts | >= 5 | >= 5 | >= 5 | Can amend with 2" of soil media or plant-derived compost to increase infiltration | < 5 acres, capture runoff from 10-20% of the IPCDA, soil could also be 50/50 sand soil mix instead of bioretention media | Compost amendments over full length and width | ||||||||
Max. Velocity For 4 hr. 25 mm(Chicago) | 0.5 m/s | 0.5 m/s | 0.5 m/s | |||||||||||
Setback from building Foundation(m) | 4 | 4 | ||||||||||||
(Impervious drainage/treatment) area | 5:1 to 10:1 | 5:1 to 10:1 | CDA < 5 acres and WQV peak flow < 3 cfs | CDA < 2.5 acres | CDA <15000 ft2 | |||||||||
longitudinal slope | (0.5-4.0)%,check dam for >3% | (0.5-4.0)%,check dam for >3% | (0.5-6.0) %, check dam for >3% | |||||||||||
Bottom width (m) | 0.75-3.0 | 0.75-3.0 | 0.75-3.0 | |||||||||||
Length | >= contributing roadway length | |||||||||||||
Flow depth (mm) (25 mm Chicago storm event) | max 100 (25 mm storm) | max 100 (25 mm storm) | max 100 (25 mm storm) | |||||||||||
Side slope (H:V) | Max. 2.5:1 , 4:1 where space permits | Max. 2.5:1 , 4:1 is prefered | Max. 2.5:1 , 4:1 where space permits | |||||||||||
Soil Amendments | ||||||||||||||
depth (mm) | 300 | 300 | 300 | |||||||||||
Oganic content | 8-15% by weight | 8-15% by weight | 8-15% by weight | 3-15% | 5-10 % | |||||||||
Grass height (mm) | 75-150 | 150 | ||||||||||||
Gravel diaphram | ||||||||||||||
Diameter (mm) | 3-10 | 3-10 | ||||||||||||
Min. Wide (mm) | 300 | 300 | ||||||||||||
Min. Deep (mm) | 600 | 600 | ||||||||||||
Available space of the contributing drainage area (%) | 5-15 | 5-15 | ||||||||||||
Depth between the bottom of the swale and high water table (m) | >= 1 | >= 1 | ||||||||||||
Enhanced grass swales area/contributing road surface | 1:1 | |||||||||||||
Drainage time of ponded water after the end of storm event , hr | < = 24 | |||||||||||||
CDA or Impervious ratio | < 5 acres | < 2.5 acres | ||||||||||||
Filter Media | ||||||||||||||
Sand | 50% | 85-88% | 70-85 % | 66% | 60% | |||||||||
Loam | 50% | |||||||||||||
Soil Fines | 8-12% | 10-20% (silt), max. 10% (clay) | ||||||||||||
Organic | 5-10 % | > 5% otherwise amend 2" with media | 33% | 40% | ||||||||||
CEC | > 10 | > 5 | ||||||||||||
pH | 5.5-7.5 |