(2000)Pollutant removal efficiencies are reported as ranges because they are based on a synthesis of several performance monitoring studies that were available as of 2000.</ref>||70 - 90||70 - 90||70 - 90||70 - 90||50 - 70||40 - 70
|-
|-
−
|Grass swale/perforated pipe||North York, ON<ref></ref>||75||96||93||24||84||84
+
|Grass swale/perforated pipe||North York, ON<ref name=SWAMP2002/>||75||96||93||24||84||84