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Rain Garden

Conserve water quantity. Preserve water quality.

By any other name:

  • rain garden
  • rainscaping
  • catchwater garden
  • bioretention basin
  • infiltration trench or swale
  • BMP - best management practice
  • aesthetic opportunity

 Counting Rule:

  • 3 planting zones
  • 4 days or less standing water
  • 5% of drainage area
  • 6" deep water

Why: remove pollutants, prevent erosion, prevent flooding, recharge groundwater, provide wildlife habitat, less expensive alternative to storm water ponds.

How: Use an existing or created depression large enough to hold runoff from at least 5% of the drainage area. Water depth should not exceed 6" in the rain garden. Use high organic sandy loam soil. Divide rain garden into 3 planting zones. Plant flood and drought tolerant plants. Soil and plants filter sediments, nutrients, and pollutants. Water should percolate down to recharge aquifers or move into the atmosphere through transpiration and evaporation in less than 4 days.


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