This table shows pollutant removal percentages for filtration BMPs.
Link to this table
Pollutant Removal Percentages for Filtration BMPs (Source: ASCE International BMP Database (ww.bmpdatabase.org) and Winer (CWP), 2000 (see also Appenidx N)
Practice TSS High-Med-Low3 TP High-Med-Low3 TN4 Metals4 (average of Zn and Cu) Bacteria4 Hydrocarbons4
Media Filter1 75-85-90 30-50-55 35 80 35 80
Vegetative Filter2 40-70-80 (-)51-0-35 35 80 35 80

1 For example, sand, mixed sand/peat and other geologic media

2 Grass filter/swale

3 See Appendix N discussion

4 Not enough information given in databases to differentiate ype of filter so both combined for this entry