Vegetated filter strips
Revision as of 00:05, 6 November 2017 by Jenny Hill (talk | contribs)
Overview[edit]
Modeling[edit]
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. See Turf for ideas of a good number according to mowing practices. |
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 around 0.4, unless otherwise tested. |
Field capacity (fraction) | Will vary according to native or amended topsoil[1] |
Wilting point (fraction) | |
Conductivity (mm/hr) | |
Conductivity slope | |
Suction head (mm) | |
Design drawdown time (hrs) | Will be determined by regulatory authority, often 48 - 72 hours to reduce nuisance from mosquitoes |
Gallery[edit]
Unmown wildflower meadow roadside filter strip/verge in Delft
Filter strips between the bioretention facility and the adjacent parking lot reduce sediment loading to the surface of the bioretention cell. Dennis Ave Health Center, Wheaton, MD. Photo credit: Moreau1
- ↑ 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.