Code
U06
Sector
Urban
Other sector(s)
Agriculture
The complete description of the NWRM
Summary

Filter strips are uniformly graded, gently sloping, vegetated strips of land that provide opportunities for slow conveyance and (commonly) infiltration. They are designed to accept runoff as overland sheet flow from upstream development and often lie between a hard-surfaced area and a receiving stream, surface water collection, treatment or disposal system.

Filter strips are generally planted with grass or other dense vegetation to treat the runoff through vegetative filtering, sedimentation, and (where appropriate) infiltration. They are often used as a pre-treatment technique before other sustainable drainage techniques (e.g. swales, infiltration and filter trenches). Filter strips are best suited to treating runoff from relatively small drainage areas such as roads and highways, roof downspouts, small car parks, and pervious surfaces.

Filter strips can serve as a buffer between incompatible land uses, and can provide locations for groundwater recharge in areas with pervious soils.  Filter strips are often integrated into the surrounding land use, for example public open space or road verges. Local wild grass and flower species can be introduced for visual interest and to provide a wildlife habitat.

Illustration(s)

Small filter strip in urban area

Source: Andras Kis’ presentation, NWRM Workshop 1

Filter strip in agriculture area

Source: http://www.nrcs.usda.gov/Internet/FSE_MEDIA/nrcs144p2_021118.jpg

Possible benefits with level
Benefits Level
ES3 - Natural biomass production
Low
ES4 - Biodiversity preservation
Medium
ES5 - Climate change adaptation and mitigation
Low
ES6 - Groundwater/aquifer recharge
Low
ES7 - Flood risk reduction
Low
ES8 - Erosion/sediment control
Medium
ES9 - Filtration of pollutants
High
ES11 - Aesthetic/cultural value
Medium
PO2 - Improving status of physico-chemical quality elements
Low
PO4 - Improving chemical status and priority substances
Low
PO7 - Prevent surface water status deterioration
Medium
PO9 - Take adequate and co-ordinated measures to reduce flood risks
Low
PO11 - Better protection for ecosystems and more use of Green Infrastructure
Medium
PO12 - More sustainable agriculture and forestry
Low
PO14 - Prevention of biodiversity loss
Medium
BP2 - Slow runoff
Low
BP6 - Increase infiltration and/or groundwater recharge
Low
BP7 - Increase soil water retention
Low
BP9 - Intercept pollution pathways
High
BP10 - Reduce erosion and/or sediment delivery
High
BP14 - Create terrestrial habitats
Medium
BP16 - Reduce peak temperature
Low
BP17 - Absorb and/or retain CO2
Low

Case studies per NWRM