This table shows comparison of phosphorus removal for different BMPs.a,e,f Values represent the percent of incoming pollutant that is removed. Source: MPCA Minnesota Stormwater Manual.
Link to this table

Information: Removal rates shown here are composite averages intended solely for use in comparing performance between BMP designs and for use in calculating load reduction in site-based TP models. They have been adapted, rounded and slightly discounted from statistical values published in BMP performance databases.
BMP group BMP design variation Average TP removal rate (%)b Maximum TP removal rate (%)c Average soluble P removal rate (%)d,f,g
Bioretentionf Underdrain see Phosphorus credits for bioretention systems with an underdrain see Phosphorus credits for bioretention systems with an underdrain see Phosphorus credits for bioretention systems with an underdrain
Infiltrationh
  • 100 for infiltrated portion
  • 0 for non-infiltrated portion
  • 100 for infiltrated portion
  • 0 for non-infiltrated portion
  • 100 for infiltrated portion
  • 0 for non-infiltrated portion
Filtration Sand filter 50 55 0
Dry swale 50 55 0
Wet swale 0 35 0
Infiltrationf Infiltration trenchh
  • 100 for infiltrated portion
  • 0 for non-infiltrated portion
  • 100 for infiltrated portion
  • 0 for non-infiltrated portion
  • 100 for infiltrated portion
  • 0 for non-infiltrated portion
Infiltration basinh
  • 100 for infiltrated portion
  • 0 for non-infiltrated portion
  • 100 for infiltrated portion
  • 0 for non-infiltrated portion
  • 100 for infiltrated portion
  • 0 for non-infiltrated portion
Stormwater ponds Wet pond 50 75 0
Multiple pond 60 75 0
Stormwater wetlands Shallow wetland 40 55 0
Pond/wetland 0

aRemoval rates show in table are a composite of five sources:

  • Caraco (Center for Watershed protection, 2001)
  • Maryland Department of the Environment](2000)
  • Winer (Center for Watershed Protection, 2000)
  • P8 modeling (William Walker)

b Average removal efficiency expected under MPCA Sizing Rules 1 and 3
c Upper limit on phosphorus removal with increased sizing and design features, based on national review
d Average rate of soluble phosphorus removal in the literature
e See section on calculating credits for each BMP in this Manual.
f Note that the performance numbers apply only to that portion of total flow actually being treated; it does not include any runoff that bypasses the BMP
gNote that soluble P can transfer from surface water to groundwater, but this column refers only to surface water
hNote that 100% is assumed for all infiltration, but only for that portion of the flow fully treated in the infiltration facility; by-passed runoff or runoff diverted via underdrain does not receive this level of treatment.

This page was last modified on 15 July 2015, at 09:21.

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