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Below is a summary of requirements, recommendations and other information for using the Minimal Impacts Design Standards (MIDS) calculator for bioretention BMPs.
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*Required
 
*Required
 
**3 foot separation from the bottom of the bioretention system to seasonal high water table
 
**3 foot separation from the bottom of the bioretention system to seasonal high water table
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**Field tested infiltration rates over table values
 
**Field tested infiltration rates over table values
 
*Information – provide links to the following*Guidance on determining infiltration rates
 
*Information – provide links to the following*Guidance on determining infiltration rates
**Information site constraints (shallow soil, karst, etc.)
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**Information on [[
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Stormwater infiltration and constraints on infiltration|site constraints]] (shallow soil, karst, etc.)
 
**Information on assessing BMPs
 
**Information on assessing BMPs
 
**Information on design metrics (high flow bypass, ponding depths, drawn down)
 
**Information on design metrics (high flow bypass, ponding depths, drawn down)

Revision as of 16:30, 6 May 2013

Below is a summary of requirements, recommendations and other information for using the Minimal Impacts Design Standards (MIDS) calculator for bioretention BMPs.

  • Required
    • 3 foot separation from the bottom of the bioretention system to seasonal high water table
    • Use most restrictive infiltration rate within 3 feet of the bottom of the BMP
    • Drawdown time of 24 hours for trout streams
    • For measured infiltration rates, apply a safety factor of 2 (2.5 for permeable pavement)
    • Pretreatment
  • Recommend
    • 5 acre or less for contributing area
    • Maximum ponding depth of 18 inches, reduced to 6 inches if there is no site information (4 feet for infiltration basin)
    • Field tested infiltration rates over table values
  • Information – provide links to the following*Guidance on determining infiltration rates
    • Information on [[

Stormwater infiltration and constraints on infiltration|site constraints]] (shallow soil, karst, etc.)

    • Information on assessing BMPs
    • Information on design metrics (high flow bypass, ponding depths, drawn down)
    • Guidance on pretreatment
    • Information on soil mixes
    • Plant information, including species list that show water tolerance, potential effects of different species on infiltration rates, planting guidance
    • Construction specifications
    • Information on operation and maintenance