Difference between revisions of "Requirements, recommendations and information for using bioretention BMPs in the MIDS calculator"
m |
m |
||
| Line 1: | Line 1: | ||
Below is a summary of requirements, recommendations and other information for using the Minimal Impacts Design Standards (MIDS) calculator for bioretention BMPs. | Below is a summary of requirements, recommendations and other information for using the Minimal Impacts Design Standards (MIDS) calculator for bioretention BMPs. | ||
| + | {{alert|The following are requirements of the [http://www.pca.state.mn.us/index.php/water/water-types-and-programs/stormwater/construction-stormwater/index.html Minnesota Construction Stormwater General Permit]|alert-danger}} | ||
*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 | ||
Revision as of 19:55, 16 May 2013
Below is a summary of requirements, recommendations and other information for using the Minimal Impacts Design Standards (MIDS) calculator for bioretention BMPs.
Warning: The following are requirements of the Minnesota Construction Stormwater General Permit
- 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 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 of bioretention BMPs.