Changes

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! Rowspan=2|Location

! Rowspan=2|Location

! Colspan=2|Runoff reduction

! Colspan=2|Runoff reduction, by length of strip

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!2 - 5 m

!2 - 5 m

===Water Quality===

===Water Quality===

Vegetated filter strips can provide moderate pollutant removal from runoff. Research suggests that runoff pollutant concentrations and loads decrease when treated with filter strips and that steady state pollutant levels are typically achieved within 5 m of the pavement edge <ref name='Barrett2004/>.

Vegetated filter strips can provide moderate pollutant removal from runoff. Research suggests that runoff pollutant concentrations and loads decrease when treated with filter strips and that steady state pollutant levels are typically achieved within 5 m of the pavement edge <ref>Barrett, M., Lantin, A., Austrheim-Smith, S. 2004. Stormwater pollutant removal in roadside vegetated buffer strips. Transportation Research Record. No. 1890, pp. 129-140.</ref>.

Based on a synthesis of performance monitoring studies as of 2000, it was reported that pollutant removal efficiencies of vegetated filter strips are highly variable. For this reason, filter strips should be used in conjunction with other water quality best management practices (e.g., as pretreatment).

Based on a synthesis of performance monitoring studies as of 2000, it was reported that pollutant removal efficiencies of vegetated filter strips are highly variable. For this reason, filter strips should be used in conjunction with other water quality best management practices (e.g., as pretreatment).

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Performance of filter strips has also been evaluated based on the Roadside Vegetated Treatment Sites Study <ref name='Barrett2003'/> and the BMP Retrofit Pilot Study <ref>California Department of Transportation (Caltrans). 2004. BMP Retrofit Pilot Program, Final Report, CTSW-RT-01-050. Sacramento, CA.</ref>. These studies concluded that concentration reductions consistently occur for TSS and total heavy metals and frequently for [[heavy metals|dissolved metals]]. [[Nutrients|Nutrients]] concentrations remained generally unchanged. When vegetation cover on the filter strip is below 80% water quality performance declines.

Performance of filter strips has also been evaluated based on the Roadside Vegetated Treatment Sites Study <ref name='Barrett2003'/> and the BMP Retrofit Pilot Study <ref>California Department of Transportation (Caltrans). 2004. BMP Retrofit Pilot Program, Final Report, CTSW-RT-01-050. Sacramento, CA.</ref>. These studies concluded that concentration reductions consistently occur for TSS and total [[heavy metals]] and frequently for dissolved metals. [[Water quality#Nutrients|Nutrients]] concentrations remained generally unchanged.  

[[Category:Water quality]]

[[Category:Performance]]