Pollutant removal percentages for bioretention BMPs. Source Winer, 2000.
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Practice TSS Total Phosphorus Total nitrogen Metals1 Bacteria Hydrocarbons
Bioretention 852
  • 100 for water that is infiltrated
  • see [1] for water that passes through an underdrain
  • 0 for water bypassing the bioretention BMP
50 95 352 80

1 Average of zinc and copper
2 Assumed values based on filtering practice performance