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| **Construction specifications | | **Construction specifications |
| **Information on operation and maintenance | | **Information on operation and maintenance |
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− | *3 foot separation from the bottom of the bioretention system to seasonal high water table
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− | *Use most restrictive infiltration rate within 3 feet of the bottom of the BMP
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− | *Drawdown time of 24 hours for trout streams
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− | *For measured infiltration rates, apply a safety factor of 2 (2.5 for permeable pavement)
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− | *Pretreatment
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− | #Recommend
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− | *5 acre or less for contributing area
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− | *Maximum ponding depth of 18 inches, reduced to 6 inches if there is no site information (4 feet for infiltration basin)
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− | *Field tested infiltration rates over table values
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− | #Information – provide links to the following
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− | *Guidance on determining infiltration rates
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− | *Information site constraints (shallow soil, karst, etc.)
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− | *Information on assessing BMPs
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− | *Information on design metrics (high flow bypass, ponding depths, drawn down)
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− | *Guidance on pretreatment
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− | *Information on soil mixes
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− | *Plant information, including species list that show water tolerance, potential effects of different species on infiltration rates, planting guidance
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− | *Construction specifications
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− | *Information on operation and maintenance
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