Difference between revisions of "Filter strips: TTT"
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|Porosity (fraction)||Suggest range 0.35 – 0.4, unless otherwise tested | |Porosity (fraction)||Suggest range 0.35 – 0.4, unless otherwise tested | ||
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− | |Field capacity (fraction)|| | + | |Field capacity (fraction)||Rowspan=5|Will vary according to native or amended topsoil<ref name = SWMM/> |
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− | |Wilting point (fraction)|| | + | |Wilting point (fraction)||Will vary according to native or amended topsoil<ref name = SWMM/> |
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− | |Conductivity (mm/hr)|| | + | |Conductivity (mm/hr)||Will vary according to native or amended topsoil<ref name = SWMM/> |
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− | |Conductivity slope|| | + | |Conductivity slope||Will vary according to native or amended topsoil<ref name = SWMM/> |
|- | |- | ||
− | |Suction head (mm)|| | + | |Suction head (mm)||Will vary according to native or amended topsoil<ref name = SWMM/> |
|- | |- | ||
|Design drawdown time (hrs)||? | |Design drawdown time (hrs)||? | ||
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[[category:modeling]] | [[category:modeling]] |
Revision as of 01:38, 12 September 2017
Surface | |
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Berm height (mm) | This is the height of the curb which constrains the overland sheet flow of water. Where the bottom of the slope discharges directly into another LID facility without impedance, the value is 0. |
Surface roughness (Manning’s n) | Lower numbers indicate less surface obstruction and result in faster flow. Suggested range for mown grass (dependent on density) 0.03 – 0.06 [1] |
Surface slope (%) | If the slope > 3%, consider using level spreaders to reduce erosion of the surface under high flow velocities. |
Soil (native underlying soil, or amended topsoil) | |
Thickness (mm) | If topsoil has been amended Absorbent landscapes |
Porosity (fraction) | Suggest range 0.35 – 0.4, unless otherwise tested |
Field capacity (fraction) | Will vary according to native or amended topsoil[1] |
Wilting point (fraction) | Will vary according to native or amended topsoil[1] |
Conductivity (mm/hr) | Will vary according to native or amended topsoil[1] |
Conductivity slope | Will vary according to native or amended topsoil[1] |
Suction head (mm) | Will vary according to native or amended topsoil[1] |
Design drawdown time (hrs) | ? |
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Oregon State Univ., Corvallis. Dept. of Civil, Construction and Environmental Engineering.; Environmental Protection Agency, Cincinnati ONRMRL. Storm Water Management Model Reference Manual Volume I Hydrology (Revised). 2016:233. https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=P100NYRA.txt Accessed August 23, 2017.