Green Streets and Water Creating liveable sustainable streets through new design and adaptation An exploration of SUDS and landscape issues
Illman Young Landscape Design A landscape and environmental practice specialising in: Masterplanning and site design Landscape appraisals and environmental assessments Project planning through to site inspection Our ambition: To create innovative, practical and sustainable landscapes Our practice
SUDS Research Illman Young in partnership with the University of Gloucestershire Completed 2 year research project Research into the design of SUDS that are functional, attractive and ecological Investigation of existing schemes within the UK and abroad Development of Good Practice Guidelines and SUDS Training SUDS Pilot projects Ongoing relationship with university
Green Streets and Water Green Mission Statement Management of water in streets Making streets more user friendly Climate change Reduction of surface water in existing sewers Increasing sewers not sustainable Introduction
What is the problem? Increased development creates extensive hard surfaces Sealing of ground prevents rain water from percolating into the soil Up to 80% of total rainfall turns into runoff within developed sites Larger amounts of water travel faster over hard surfaces Localised flooding Runoff traditionally collected in pipes Directed as quickly as possible into the nearest watercourse Problems of flooding and pollution Traditional drainage
What is the problem? Urban runoff effects in Gloucestershire, July 2007
What is the problem? Known flooded properties in Gloucestershire, July 2007
The problem Studies undertaken by Welsh Water compared increases of impermeable surfaces within typical housing developments in Cardiff: 20% increase in impermeable surfaces from1984-2009 through building of extensions, paving over front gardens, etc. 35% increase predicted by 1934 if urban creep continues as at present. Increase in impermeable surfaces
The problem Studies showed that if we continue as at present runoff (and potential flooding) will increase by approximately 32% by 2031. If flows from future development are controlled, flows will increase by approximately 28% by 2031. Therefore we must reduce both existing and future development runoff to just maintain present. Increase in impermeable surfaces
SUDS Legislation Surface run-off increasingly causes flooding 80,000 homes or more are currently at risk 270+ million of insured damage each year June 2007 floods 2/3 properties flooded by drainage systems Traditional systems have limited capacity Sewer surcharging and pollution incidents Promote SUDS as an alternative Surface Water Management Plans Consultation to resolve ownership/adoption Defra : Future Water
SUDS Legislation Acknowledges that SUDS are essential for reducing future flood risk Runoff should be managed in sustainable manner to mimic flows prior to development Design for events exceeding design capacity RPBs and LPAs should promote SUDS Incorporate SUDS into RSS and LDF Promote SUDS to achieve wider benefits such as water quality, biodiversity and amenity Planning Policy Statement (PPS25)
SUDS Legislation Modernise and consolidate existing legislation Reflect recommendations from Pitt Review and Future Water Likely measures include: LPAs to take responsibility for local flood risk management LPAs to adopt SUDS on highways and in public realm Removal of automatic right to connect New pricing policy by water companies Proposed Floods and Water Bill 2009
Surface Water Management Plans Guidance on implementing SWMPs for LPAs. Based on Pilot Studies and recommendations from the Pitt Review and Future Water. Importance of SUDS to manage increases in flood risk. SUDS to provide water quality and amenity benefits. SWMPs provide a framework and set of standards. Image: Defra Catchment Planning
How does it work in nature? Hydrological Cycle
How do SUDS work? Inspiration from nature
What makes them different? Conventional drainage systems Quantity Sustainable drainage systems Quantity Amenity/ Biodiversity Quality Amenity/ Biodiversity Quality SUDS Triangle
The Management Train Evapotranspiration Conveyance Source Control Site Control Regional Control Infiltration or recharge Drainage techniques used in series
Benefits of SUDS in Streets? Protect urban areas from flooding Protect watercourses from pollution Provide source control Recharge groundwater Provide green corridors Beautiful landscape features Tree Planting Traffic Calming Improvement of micro climate Photo: Welsh Water
Water Management based Masterplans Interdisciplinary approach SUDS integrated into landscape Buildings located appropriately Sufficient space provided
North East Cardiff The Site
North East Cardiff Original masterplan
North East Cardiff Catchment Plan
North East Cardiff Conceptual SUDS Strategy
North East Cardiff Typical road sections
North East Cardiff Plan: Barton Willmore Integrated masterplan
Cribbs Causeway, Bristol The site
Cribbs Causeway, Bristol Hydrology of catchment
Cribbs Causeway, Bristol Natural flow of water
Cribbs Causeway, Bristol Run-off from hard surfaces
Cribbs Causeway, Bristol SUDS Strategies
Cribbs Causeway, Bristol Typical Major Road
Cribbs Causeway, Bristol Typical Residential Street
Cribbs Causeway, Bristol Typical Mews
Cribbs Causeway, Bristol open channels swales along road/source control Detention basin with permanent pond Site control feature open canal Conveyance to regional control feature Detailed studies
New Street Designs Photo: wsud Large swales along main roads
New Designs Photo: Dreiseitl Photo: Dunnett Large swales along main roads
New Street Designs Photo: La Citta Vita Urban Wetlands along residential street
New Street Designs Channels and rills within Mews
New Designs Photo: Dreiseitl Open water features within Mews
New Designs Ditches kept within new development
Retrofitted Streets ZONES 2 3 2 9 4 8 5 7 7 1 1 : The Gateway 2 : The Liveable Street 3 : The Civic Space 4 : The Neighbourhood Node 5 : The Community Garden 6 : The Health Garden 7 : The Suds System 8 : The Play Spaces 9 : The Green Network 9 1 6 BRE Submission
BRE Submission 1 : Kinetic Ramp with Soakaway 2 : Planted Channel Partial Infiltration 3: Planted Swale Partial Infiltration 4 : Rain Water Planters 5: Water Cascade Suds and Ornamental Planted Water Feature 6 : Sunken Area Attenuation of Larger Flood Events 7 : Discharge Point 8 : Full Infiltration With Rocks and Planting Integrated with Play 9 : Shallow Channel with Rocks and Planting 10 : Dished Channel 11 : Permeable Paving 12 : Water Recycling System 13 : Flood Flow Routes SUDS Strategy
BRE Submission Planted Channel - Partial Infiltration Planted Swale Partial Infiltration Typical Sections
Retrofitted SUDS schemes Images: Portland Bureau of Environmental Services Green Street Project in Portland
Retrofitted SUDS schemes Photo: City of Vancouver Photo: Seattle Public Utilities Photo: Seattle Public Utilities Retrofitted Swales
Retrofitted SUDS schemes Filter drains along streets
Retrofitted SUDS schemes Portland Bureau of Environmental Services Nigel Dunnett Portland Bureau of Environmental Services Stormwater Planters
Retrofitted SUDS schemes Photo: WSUD Photo: WSUD Portland Bureau of Environmental Services Kerb Extensions
Retrofitted SUDS schemes Open channels and canals
Larger Control features Photo: Dreiseitl Detention basin with wetland
What are the perceived challenges? LACK OF KNOWLEDGE of the influence of the background geography of catchments of the best designed examples of the water quality impacts of the benefits of a fully sustainable approach to water management of unfamiliar methods of construction about retrofitting SUDS FEAR of health and safety issues of adoption issues of maintenance costs of long-term management INAPPROPRIATE REGULATION Building regulations By government departments
Opportunities Use water as a resource Allow water back into the city Create visible routes for water Deal with flooding locally Ensure clean water environment Provide habitat and Enhance biodiversity Use SUDS as a design element Create beautiful landscape features
Let s celebrate water Photo: Portland Bureau of Environmental Services in our streets!