Step 6. Pollutant Removal

This matrix examines the capability of each STP option to remove specific pollutants from stormwater runoff. The matrix includes data for:

In some communities, on-site load calculation is required, and this matrix is critical. In others, these values may be replaced with relative (i.e., "high, low, moderate") pollutant removals. Also, a community may choose to focus on only one or two target pollutants to protect a specific resource.

STP Selection Matrix 6. Pollutant Removal
STP Group TSS TP TN Metals1 Bacteria
Ponds 80 51 33 62 70
Wetlands 76 49 30 42 782
Filters3 86 59 38 69 372
Infiltration 952 70 51 992 N/A
Open Channels 4 81 342 842,5 61 -252
1: Average of zinc and copper. Zinc only for infiltration practices.
2: Based on fewer than five data points.
3: Excludes vertical sand filters and filter strips.
4: Highest removal rates for dry swales
5: No data available for grass channels
N/A: Data not available