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|Seepage (mm/hour)||Rate of seepage loss into the surrounding soil
 
|Seepage (mm/hour)||Rate of seepage loss into the surrounding soil
 
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!colspan = "2" style="background: darkcyan; color: white; align = center"|Surface
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|width = 210px|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. 
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|Surface roughness (Manning’s n)||Lower numbers indicate less surface obstruction and result in faster flow. <br>
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Suggested range for mown grass (dependent on density) 0.03 – 0.06 <ref name = SWMM> 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.</ref>
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|Surface slope (%)||If the slope > 3%, consider using small [[Checkdams]] or weirs to permit temporary ponding, increase infiltration, and slow flow to reduce erosion. 
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|Swale side slopes (run/rise)||Suggested value of 3 or 4 if design permits [[Enhanced swales]]
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[[Category: modeling]]
 
[[Category: modeling]]
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