General National Id Norway_01 Site name Fornebu Light or indepth? In-depth The in-depth description of the case study cs-nor-01-final_version.pdf RBD code NO5101 Transboundary 0 Data provider Martyn Futter SLU Source(s) Sustainable stormwater management at Fornebu “ from an airport to an industrial and residential area of the city of Oslo, Norway From airport to sustainable community sustainable Fornebu The aesthetic performance of urban landscape-based stormwater management systems: a review of twenty projects in northern Europe NWRM(s) implemented in the case study Permeable surfaces Swales Filter Strips Detention Basins Retention Ponds Longitude 10.6229 Latitude 59.9019 Site information Climate zone cool temperate moist Mean rainfall 778 Mean rainfall unit mm/year Average temperature 6 Mean evaportranspiration 200 Mean evaportranspiration unit mm/year Mean runoff 0,00256849313154817 Mean runoff unit 600 - 750 mm Average imperviousness 40 Type Actual Test Site Average slope range 0-1% Vegetation class grass/turf Monitoring maintenance Administrative annual cost information Administrative costs are not known Design & implementations Application scale City Performance timescale Immediate Area (ha) 340 Area subject to Land use change or Management/Practice change (ha) 340 Size unit ha Design capacity description The systems were designed based flows expected with a 1 year return period for channels and a 20 year return period for detention ponds. The average runoff was based on estimates of daily summer rainfall between 1957 and 1995. The wet ponds had design criteria of 230 m3 per effective hectare. Basis of design The NWRM are deisgned to treat a range of events with return times ranging from 1 to 20 years. Design criteria are based on long-term average summer rainfall. Constraints Winter conditions, snow and ice are a challenge to the implmentation of sustainable urban drainage systems at Fornebu and other northern cities. Favourable preconditions Having a brownfield site and a governance environment favorable to sustainable multi use urban landscape were key factors in the success of Fornebu. Crop rotation none Design contractual arrangement Arrangement type Responsibility Role Comments Name Design consultation activity Activity stage Key issues Name Comments Design land use change Land use change type Discontinuous urban fabric Design authority Authority type Role Responsibility Name Comments Other Initiation of the measure Statsbygg Statsbygg is the Norwegian Directorate of Public Construction and Property Other Implementation Statsbygg Other Financing Statsbygg Other Determination of design details of the measure City of Oslo Other Determination of design details of the measure Municipality of Baerun Lessons, risks, implications... Key lessons Success was dependent on communication between different levels of government and a clear vision for a sustainable, multi-use urban environment Success factor(s) Success factor type Success factor role Comments Financing possibilities Attitude of decision makers Attitude of relevant stakeholders Financing Financing type Comments National funds Local funds Barrier Barrier type Barrier role Comments Lacking coordination between authorities Driver Driver type Driver role Comments Organisation committed to it main driver Financing share Financing share type Share Comments Policy, general governance and design targets Policy target Target purpose Runoff control Peak-flow reduction Pollutants Removal Oher Societal Benefits Increase Water Storage Groundwater Recharge Improved Biodiversity Policy pressure Pressure directive Relevant pressure Policy area Policy area type Policy area focus Name Comments Policy impact Impact directive Relevant impact Policy wider plan Wider plan type Wider plan focus Name Comments Policy requirement directive Requirement directive Specification Socio-economic Direct benefits information The Fornebu brownfield redevelopment has clear direct benefits as it provides space for living, employment and recreation in a crowded urban area. The specific benefits of the NWRM in Fornebu are harder to quaknitfy as they cannot really be considered in themselves but must be seen as part of the complete redevelopment picture. Ancillary benefits information Key ancillary benefits include more living space and a sustainable multi use urban environment supporting recreation, residential and industrial land use. Costs investment information Total investment cost is not known Costs land acquisition information No land acquisition costs as land was already owned by Norwegian government Costs operation maintenance unknown Costs total information Total cost is not known Ecosystem improved biodiversity 1 Information on Ecosystem improved biodiversity more aquatic habitat and greenspace Biophysical impacts Information on retained water The total retained volume of water is hard to assess as the Fornebu plan consists of multiple NWRM and Green Infrastrucutre measures Increased water storage 230 Increased water storage unit m3/ha Information on runoff reduction Large qualitiative reductions in runoff peaks could be expected Information on Peak flow rate reduction Large qualitative reductions in peak flow could be expected when compared to the old Fornebu airport Ecosystem erosion control 0 Water quality overall improvements Positive impact-WQ improvement Information on Water quality overall improvements based on mdeolling results and design criteria Water quality Improvements Phosphorus (P) 60 Water quality Improvements (P) unit % reduction pf pollutant Water quality Improvements Nitrogen (N) 40 Wq Improvements n unit % reduction pf pollutant Water quality Improvements Total Suspended Solid (TSS) 80 Water quality Improvements (TSS) unit % reduction pf pollutant Water quality Improvements Copper (Cu) 65 Water quality Improvements (Cu) unit % reduction pf pollutant Water quality Improvements Zinc (Zn) 45 Water quality Improvements (Zn) unit % reduction pf pollutant Soil quality overall soil improvements Positive impact-SQ improvement Information on Soil quality overall soil improvements improvements related mainly to brownfield cleanup and removal of 200000m3 contaminated soil Information on Soil quality overall soil pollution brownfield improvement included removal of contaminated soil, PAH, oil and deicing fluids were all problems Full Context Pathway(aka Context) Default view Area(aka Level or Site) ALL