Code U10 Sector Urban Other sector(s) Agriculture Forest Hydro Morphology The complete description of the NWRM u10_-_detention_basins.pdf Summary Detention basins are vegetated depressions designed to hold runoff from impermeable surfaces and allow the settling of sediments and associated pollutants. Stored water may be slowly drained to a nearby watercourse, using an outlet control structure to control the flow rate. Detention basins do not generally allow infiltration: see U12 for infiltration basins.Detention basins can provide water quality benefits through physical filtration to remove solids/trap sediment, adsorption to the surrounding soil or biochemical degradation of pollutants. Detention basins are landscaped areas that are dry except in periods of heavy rainfall, and may serve other functions (e.g. recreation), hence have the potential to provide ancillary amenity benefits. They are ideal for use as playing fields, recreational areas or public open space. They can be planted with trees, shrubs and other plants, improving their visual appearance and providing habitats for wildlife. Illustration(s) Infiltration basinSource: Andras Kis’ presentation, NWRM Workshop 1 Possible benefits with level Benefits Level ES1 - Water storage Medium ES3 - Natural biomass production Low ES4 - Biodiversity preservation Medium ES5 - Climate change adaptation and mitigation Medium ES6 - Groundwater/aquifer recharge Low ES7 - Flood risk reduction High ES8 - Erosion/sediment control Medium ES9 - Filtration of pollutants Medium ES10 - Recreational opportunities Medium 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 High PO11 - Better protection for ecosystems and more use of Green Infrastructure High PO12 - More sustainable agriculture and forestry Low PO14 - Prevention of biodiversity loss Medium BP1 - Store runoff High BP2 - Slow runoff High BP5 - Increase evapotranspiration Medium BP6 - Increase infiltration and/or groundwater recharge Low BP7 - Increase soil water retention Low BP9 - Intercept pollution pathways Medium BP10 - Reduce erosion and/or sediment delivery Medium BP14 - Create terrestrial habitats Medium BP16 - Reduce peak temperature Low BP17 - Absorb and/or retain CO2 Low Case study(ies) Sustainable stormwater management and green infrastructure in Fornebu, Norway Leidsche Rijn sustainable urban development, Netherlands Full Context Pathway(aka Context) Default view Area(aka Level or Site) ALL