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Landscape Institute Inspiring great places Water Sensitive Urban Design in the UK – Ideas for built environment practitioners

Authors of this engagement document: Celeste Morgan (lead author), AECOM Cristian Bevington, AECOM David Levin, AECOM Peter Robinson, AECOM Paul Davis, Arup Justin Abbott, Arup Paul Simkins, Arup

Designed by: Saurabh Vaidya (illustrations), AECOM This document is an output from CIRIA’s project on Water Sensitive Urban Kelly Sharman (graphic design), AECOM Design in the UK – a scoping study (CIRIA project RP976) and developed with support from CIWEM, the ICE, the Landscape Institute, RTPI and the CIRIA project managers: Urban Design Group . Louise Clarke This document provides an overview that sets out the drivers, benefits and Paul Shaffer vision for Water Sensitive Urban Design (WSUD) in the UK and is based on findings from a collaborative project that included extensive consultation Project steering group chair: and a literature review to understand the role of WSUD in the UK. There Richard Ashley, University of Sheffield is a more detailed scoping study available from www.ciria.org (CIRIA publication C724). The project outputs have been developed by AECOM and Project funders: Arup under contract to CIRIA with support from a project steering group ACO and funding from those organisations listed and on the back cover. Defra Dwr Cymru Welsh Water Publication C723 Environment Agency ©CIRIA 2013 Engain RP976 Formpave ISBN 978-0-86017-726-5 Glasgow City Council Halcrow Published by CIRIA, Classic House, 174-180 Old Street, London EC1V 9BP Hydro International JBA and EWater

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Contents

Support of local food productionGreater security Reduction of water supply Cost savings andImprovement efficiencies Community Knowledge sharing between disciplines local Delivery Knowledge efficiencies 03 | water, People and places Support Reduction engagement engageKnowledgement Deliverysharing Improved 04 Why Change? green | Knowledge water Improvement 05 | Introducing Water Sensitive Urban Design of ecosystemCommunity sharing local

Improvement efficiencieswaterhealth 07 | What could a water sensitive house look like? Support Pricing of water related to its quality, source wellbeing and security Community Knowledge water Improved Delivery wellbeing Reduction 08 | What could a water sensitive block of flats look like? sharing local Reduction Community green Delivery engagement 09| What could a water sensitive existing neighbourhood look like? Delivery sharing wellbeingSupport Community Deliverywater in water of green management 10 | What could a water sensitive COMMERCIAL AREA look like? local infrastructurelocal Improvement green Reduction 11 | What could a water sensitive New Development look like? engagement water SupportCreation water of more Community 12 | WHAT COULD A WATER SENSITIVE CITY LOOK LIKE? sharing KnowledgeDelivery Reduction engagement Improvement Knowledge efficiencies 13 | why we want water sensitive urban design Reduction green of flood risk efficiencies Knowledge local 15 | benefits of water sensitive urban design Reduction local efficienciesImprovementSupport attractive Delivery places 16 | what next? Community green Economic growth Reduction of carbon and and employment Improvementenergy associated with water management Delivery Reduction water Improvement Improvement of water green qualityKnowledge in watercourses water Reduction SuppwellbeingoReductionrt of Improved health urban heat and wellbeing island effect

02 water, People and places ? F l o WATER DEFINES OUR OUR PLACES CONTAIN MANY o d PLACES TYPES OF WATER E n W v a Our cities, towns and villages all have a long and Vitality: The support and sustenance Raini water intimate relationship with water and were historically for a growing population. r e located around a water source, watercourse or o r coastline as the focus point for life and trade. In Identity: The river, pond, lake or coastline n modern times, not only do we depend on clean water that has become central to the identity of our cities and towns. m supply for our daily needs, but we also depend on Surface water runoff water to grow our food and produce resources, to Activity: A provider of recreation n transport our goods and waste, beautify our urban and well-being for all. D t areas and provide fun and recreation. Water is often Greywater Wastewater central to the identity of a place. Yet the relationship Health: The supporter of essential i l ecosystems and food supplies. n between the places we live and the water resources k W we depend on is often not prioritised in the design Irr i gation water and evolution of those places. Water shortages, Landscape: A desirable landscape feature that communities love to be near. n t flooding and watercourse pollution are all signs g e of stress where developed areas have a troubled r interaction with the natural water cycle and where, W conversely, water has become a risk or a nuisance a rather than an asset or an opportunity. t e r water sensitive urban design 03

Why Change?

Affordability Flooding Water shortages Watercourse health of water

20 million customers in the UK Flooding in parts of the UK in 2007 27% of water bodies in England do not We need to keep water bills experienced hose pipe bans in 2012 killed 13 people and cost the meet water quality standards. affordable while recognising the to limit stress on water resources. economy £3,200,000,000. This will Significant investment is being made to increasing strain on water resources. increase if left unchecked. improve the quality of the UK’s water Surface water runoff courses to meet European standards.

Re-connect Encourage people with cross-disciplinary Support liveable water working Support growth urban places

Urban places and spaces have Practitioners involved in water The population continues to grow and London loses 2.5 Hyde Parks of green become detached from water as management and in designing demand new water infrastructure. space per year as gardens are paved infrastructure has been hidden places are often not working Already water-stressed south east over. Climate change will heighten underground. closely enough. England will grow by 23% by 2035. heat stress in paved urban areas.

04 Introducing Water Sensitive Urban Design

Urban Local climate Design Sustainable and buildings Water Sensitive Urban Design is the human process of integrating water cycle comfort Local Carbon management with the built environment identity reduction through planning and urban design. Community engagement Lush Sustainable landscapes Two principles are essential to its application: water supply 1 All elements of the water cycle and their 2 Consideration of the water cycle is made Water interconnections are considered concurrently from the outset, and throughout the design features Urban to achieve an outcome that sustains a healthy and planning process. Accordingly, water and art Demand food production Rainwater natural environment while meeting human management solutions seek to meet the management + and gardening and surface greywater and needs. This includes managing: expectations and aspirations for design of water runoff wastewater successful places, such as: recycling Place Integrated recycling Productive a Water demand and supply Making water cycle landscape b Wastewater and pollution a Celebrating local character, environment management c Rainfall and runoff and community Open Surface water Wastewater Local d Watercourses and water resources b Optimising the cost-benefit of spaces runoff reduction Reduced reduction and resource infrastructure and built form and and treatment e Flooding and water pathways pollution treatment management c Improving quality of life for communities recreation + and flood flood water d Providing resource security and risk integration Local resilience in the future. Affordable infrastructure water and efficiency good service

Flood Habitat pathway creation integration and enhancement Street Complimentary and land highway use water design Urban planning sensitive Planning urban design 05 When consulting with built environment professionals about water sensitive urban design:

56% of the survey Water Sensitive Urban Design is the process. respondents believe Water Sensitive Water sensitive places are the outcome. Urban Design to be 56% rarely practised in the UK and only 1% think it is commonly practiced.

Waste Water water quality Water Surface Urban efficiency water design and management recycling 68% of survey Green (SuDS) Surface infrastructure respondents had water heard of Water Water Water 68% Sensitive Urban Planning Sensitive quality Water Urban Design Design. supply

Urban Waste design Green Flood Planning infrastructure water risk delivery management management 83% of survey respondents believe that water Flood risk management is 83% considered too late in the planning and design process for developments. WSUD can be applied at all scales...

06 What could a water sensitive house Water Reuse One simple solution could look like? be using grey water from the sink for flushing the toilet - saving money and reducing wastewater leaving the house.

URBAN FORM: Semi-detached home Front and back garden

Water context: Green roof Downstream flooding Reduces runoff from Desire for high water quality in local harbour roof, and blends their Water security concerns house with the Water metering in place neighbouring ecological Water butt Moderate soil permeability Rain garden area. Harvests runoff Cary disconnected her back from roofs and COMMUNITY CONTEXT: downpipe to help reduce provides Cary with Cary and Tim own the house runoff from the property a water source on Cary enjoys gardening and reduce neighbourhood dry days for the Water efficient fixtures Both looking to save money flooding. It now drains to a garden and for car And Appliances Both are environmentally conscious rain garden, which soaks up washing, saving Cary and Tim save 228 bathtubs Home on edge of city bordering ecological area rain so Cary’s plants thrive them £33 on the without her watering them. full of water and £119 water and water bill. energy bills every year.

water sensitive urban design 07 What could a water Green roof Reduces runoff from the roof, improves the view, sensitive increases biodiversity and provides an urban green block of flats space for residents. It also improves temperature for look like? top floor residents. Greywater recycling Greywater from flats is Gardening recycled reducing water Capturing rainfall bills and the amount sent allows Jeremy and to sewers and treated. The his neighbours to run building manager runs a a community garden communal system. URBAN FORM: and grow vegetables without connecting to Ground floor Resilience High-rise flat The ground floor should be Public spaces are dull and unused water mains. This also naturally increases designed or retrofitted to be the ecology on-site. flood resilient and with an Water context: appropriate low-risk use to Next to river with variable level mitigate any damage that High water stress area might occur if flooding does Combined sewer system at capacity happen. COMMUNITY CONTEXT: Amy and Jeremy rent a flat for themselves and their two children Tight budgets Quiet green space Communally managed flats Converting paved No good recreation space for adults or area to green space Adaptable space children provides a pleasant Landscaped areas that are space for residents, designed to be floodable during reduces runoff and heavy rain when water levels reduces the urban rise but are great for walking, heat island effect cycling and playing the rest of (where materials like the time. concrete retain heat).

08 What could a roof water sensitive Front garden existing neighbourhood Road BEFORE: IMPERMEABLE ROADWAY AND AFTER: RETROFIT PERMEABLE SURFACES AND look like? PAVED FRONT GARDENS Sustainable Drainage Systems (SUDS) Gradual increase of impermeable area as front Returning permeability and introducing additional gardens have been paved over has increased runoff treatment and storage reduces pollution surface water runoff and pressure on existing and downstream flooding as well as improving sewer infrastructure. urban ecology, amenity and property value.

URBAN FORM: Existing medium density neighbourhood Terraced and semi-detached properties Homezone creation Water context: Creative use of landscaping Surface water flooding and vegetation creates a Strained existing infrastructure safer and more pleasant environment for pedestrians COMMUNITY CONTEXT: while reducing runoff. Family area Strong architectural character Downpipe disconnection Need for street safety and Reduces pressure on sewer pedestrian priority Water system reducing flooding and Permeable surfaces Efficiency water quality problems. Allows water to infiltrate, Retrofits reducing the amount of Water and energy water entering the sewers retrofits are Treepit rain gardens and potentially increasing made at the same Introduces more and aquifer recharge. time to minimise healthier street trees that interuption to are naturally watered by homeowners runoff. Increases urban while provding the biodiversity, property best savings. values and helps local water climate. sensitive urban design 09 Rainwater supply Wastewater supply What could a BLUE-GREEN ROOF SPACE EFFICIENT SUDS Water profile Non-potable demand Water is initially stored and Integrating permeable paving water sensitive treated on a section of the and treepit rain gardens, supermarket roof before which is used to drain the COMMERCIAL draining to the underground carpark runoff into lined storage tank. underground storage. AREA look like? SUPPLY demand

URBAN FORM: Supermarket adjoined by a carpark and carwashing facility

Water context: Surface water flooding High concentrated demand for low quality WATER MASTERPLANNING water in carwash facility By examining local demands for water, the best sources COMMUNITY CONTEXT: can be matched to the best The supermarket owners would like to use. In this case, the large maximise car parking space while creating demand for non-potable an attractive environment water from the carwash can Carwash owners looking to reduce water be best met using harvested costs runoff from the supermarket Large Scale roof and carpark. Demands Rainwater Harvesting Rainwater from both the for non-potable water in the CONVENTIONAL WASTEWATER roofs and the carpark are supermarket (toilet flushing) DRAINAGE stored underground for reuse are too low to justify a dual Carwash runs during Wastewater from the supermarket by the neighbouring carwash. supply. hosepipe bans and carwash are transferred to the Runoff from the site is greatly A local non-potable source local wastewater treatment plant. reduced. of water from harvested An on-site system could have rainwater runoff means that been used to recycle wastewater water the carwash can operate from the carwash for reuse, but sensitive during a hose pipe ban. rainwater harvesting provided urban a lower cost and lower carbon design solution. 10 Water profile Rainfall

potable demand Surface water runoff: 230 megalitres/year Non-potable demand: What could Wastewater: 140 megalitres/year 300 megalitres/year Rainwater supply a water Wastewater supply sensitive New Non-potable demand Development ecycled ter r Water Cycle study wa te Completed at masterplanning stage look like? Flood avoidance as W to inform layout and design. Holsitic Location of new development strategy formulated to manage should be outside areas ed ur water supply, wastewater and of flood risk. pt ca drainage to meet Code for r te a Sustainable Homes targets. w te s a W HIgh Standard Homes URBAN FORM: WATER RECYCLING PLANT Water efficient fixtures to New mixed use urban extension maximise water efficiency. 3500 new homes Code for Sustainable Homes level 5 target

Blue-Green corridors Water context: d le Creates channels for Driest area of the UK yc c e surface runoff to collect, be Water infrastructure needs to be r R f f u treated and flow overland extended and upgraded o n n o f through the development. Downstream flooding issues u f

R c a Creates multi-functional p t u green grid to raise value COMMUNITY CONTEXT: r e Sustainable living desired d of homes and provide Mix between rural and urban living recreation and pedestrian On-site movement corridors. Water recycling Wetlands plant Provides a natural To treat environment for water either runoff capture and filtration or wastewater and potential recharge for non-potable of aquifers. use in homes.

Local Water harvesting management and storage Dedicated management body Reduces the amount of water for development to provide and manage entering watercourses, reducing 11 water services (possibly with other services). downstream flood risk. WHAT COULD Summer water park During the summer, water capture runoff for use A WATER features are filled and Reduces pressure on infrastructure plants watered using and flood risk by using water on a SENSITIVE harvested rainwater and strategic scale. runoff. Energy CITY LOOK generation Using the LIKE? wastewater treatment plants and water flow to generate energy from captured water.

URBAN FORM: Large urban area centred on river corridor City centre dominated by paved areas Significant growth targets

Water context: Lack of capacity in sewer system Serious flood risk High rainfall and low water stress

COMMUNITY CONTEXT: Pockets of deprivation EXCEEDANCE Neighbourhood parks and recreation routes space needed Sewer mining Designed to direct Intercepting wastewater in flood waters safely away sewers to treat for irrigation of from properties during new parks in summer. Removes extreme rainfall. These routes water from strained infrastructure. could be roads or blue-green corridors where flooding can be managed. Adaptable river edges Public recreation space that Urban floodplains provides access to the river while Areas designed to flood at being designed and managed to times of high water levels. accommodate flooding. water sensitive Flood resilient housing Green grid urban If an area floods, homes and Allows surface runoff to infiltrate, design public spaces are designed so that provides a habitat for wildlife and the impacts are minimal. attractive spaces for people. 12 why we want water sensitive Spatial PLANNER: WATER COMPANY: urban design ‘This should be an ‘Holistic consideration Quotes from people working and essential component of of water in the urban catchment can deliver living in our communities delivering sustainable development. Yes, it will significant benefits over help meet runoff targets traditional approaches and water efficiency to water management. targets, but it will also By taking a holistic view support great place- of water in the urban making and add value for environment we can find communities.’ integrated solutions that look for synergies over individual solutions.’

architect/URBAN DESIGNER: LOCAL AUTHORITY: HOUSE BUILDER:

‘Water isn’t given the priority ‘We don’t want to stifle ‘Cross-disciplinary working and attention it should have in growth in the future so is essential the more you can design of the built environment. we need to be smarter do upfront, the easier it is Water is being designed out about how we plan and to take it forward. If things when really we should be design development to are brought into the process designing it in. A good design grow while maintaining too late there can be serious will carefully craft in good our natural resources.’ implications so developers water management practices want to know what is needed with occasional moments up front. We are used to a of flamboyance to celebrate changing planning context, water. Water needs to be a core so our approach has to be consideration thrown into the flexible.’ mix with all the other aspects that make great places.’ water sensitive urban design 13 Ecologist: academic: Local Resident:

‘WSUD is a very practical ‘Even though there is the desire ‘It would be great to have opportunity to develop to integrate better, market more street trees and locally appropriate forces can work against that. water for my garden, responses for water Silos can be reinforced in while at the same time management that also academia - they aren’t just in saving on energy bills. deliver green infrastructure industry. All professions involved If this can be done in a and habitat. It seems we in the built environment need way that is also water all want the same result, to be educated in a little bit of efficient and beneficial to and we can deliver great everyone else’s work and also in the environment, it would solutions by bringing pressing issues like water. We make me feel good about initiatives and skills need to think about the structure the place I live.’ together.’ of an ideal team, what everyone does, and ensure education matches those teams.’

Housing association: landscape architect: Water ENGINEER:

‘Water sensitive urban design ‘It’s impossible to ‘We typically manage water could create much more separate WSUD from in different stakeholder interesting and engaging wider sustainability boxes and I don’t think we places for local people. We opportunities. Solutions are joined up. For example often work with very small need to be community we aren’t joining the dots budgets for gardens and food specific and environment on flood risk management growing projects, and often specific – design has with water resource struggle to get a water source to be central. The good management, we could be to a site, so using new ways of news for designers is that holding onto more of our capturing water is great and they are already part of flood water for reuse rather financially beneficial. People that process. You need than rushing it out to sea.’ love the idea of creating designers who are used a peaceful and natural to working with sites and landscape in urban areas understanding sites to where kids can splash through implement WSUD.’ water areas. Huge amounts can be done if you use a little bit of imagination.’

14 Support of local food productionGreater security benefits Reduction of water supply Cost savings andImprovement of water efficiencies Community Knowledge sharing between disciplines local Delivery Knowledge efficiencies sensitive Support Reduction engagement engageKnowledgement Deliverysharing urban Improved green design ImprovementKnowledge water of ecosystemCommunity sharing local

Improvement efficiencieswaterhealth Support Pricing of water related to its quality, source wellbeing and security Community Knowledge Delivery wellbeing water ReductionImproved sharing local Reduction Community green engagementDelivery Delivery sharing wellbeingSupport Community Deliverywater in water of green management local infrastructurelocal Improvement green Reduction engagement water water SupportCreation of more Community sharing KnowledgeDelivery Reduction engagement Improvement Knowledge efficiencies Reduction green of flood risk efficiencies Knowledge local Reduction local efficienciesImprovementSupport attractive Delivery places Community green Economic growth Reduction of carbon and and employment Improvementenergy associated with water management Delivery Reduction water Improvement Improvement of water green qualityKnowledge in watercourses water Reduction SuppwellbeingoReductionrt of Improved health urban heat and wellbeing island effect

15 what next?

Water Sensitive Urban Design is an opportunity to create beautiful, successful and resilient places. It is undeniable that the relationship between water and our water urban areas needs to be given a higher sensitive priority to provide integrated solutions to urban flood risk management, sustainable water use and supply and the improvement design of water quality in our treasured watercourses. This priority needs to be applied in an integrated way by the people and partners that plan and design the CONNECT COLLABORATE CREATE built environment. In doing so, we can the water cycle with other disciplines great solutions for great places bring together the skills and creativity Seek the best solution for all Seek out others built environment Plan and design the built environment of practitioners who plan and design the aspects of the water cycle by practitioners who can bring new to respond to urban form, community places we live in to bring much wider thinking about water supply, perspectives and expertise. needs and water issues. benefits to communities. wastewater, surface water runoff and flood management.

water sensitive urban design 16 Who we are Established in 1960, CIRIA is a highly regarded, industry-responsive, not for profit research and information association, which encompasses the and built environment industries. CIRIA operates across a range of market sectors and disciplines, providing a platform for collaborative projects and dissemination by enhancing industry performance, and sharing knowledge and innovation across the built environment. As an authoritative provider of good practice guidance, solutions and information, CIRIA operates as a knowledge-base for disseminating and delivering a comprehensive range of business improvement services and research products for public and private sector organisations, as well as academia. How to get involved zzCore membership zzProject funding zzSAFEGROUNDS Learning Network Allows your employees to assist with the development of Project funders influence the direction of the research and A forum for disseminating good practice guidance on the and access to good practice guidance, formal networks, gain early access to the results. management of radioactively and chemically contaminated facilitation, conferences, workshops and training. land on UK nuclear and defence sites. zzCEEQUAL zzAssociate membership CIRIA co-manages this environmental award scheme, which zzSD:SPUR Allows your employees to access CIRIA’s services. promotes environmental quality in civil engineering and The initiative was developed to establish safe, socially, Members are able to access exclusive content via the infrastructure projects economically and environmentally sustainable practices CIRIA website. arising from the decommissioning of nuclear sites. zzLocal Authority Contaminated Land Network zzCIRIA Books Club LACL helps local authorities address responsibilities under zzLANDFoRM (Local Authority Network on Drainage and Members can buy most CIRIA publications at half price and Part IIA of the Environmental Protection Act 1990. Flood Risk Management) can attend a range of CIRIA conferences at reduced rates. A platform for sharing knowledge and expertise in flood risk zzEuropean Marine Sand and Gravel Group management and sustainable drainage. zzThe CIRIA Network CIRIA provides secretariat support to EMSAGG, including A member-based community where clients and professionals management of the Group’s conferences, workshops and zzBRMF (Brownfield Risk Management Forum) meet, develop and share knowledge about specific topics website and producing its newsletter. Promoting sustainable and good practice in brownfield relevant to construction and the built environment. projects in the UK.

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17 Core and Associate members

AECOM Ltd Morgan Sindall (Infrastructure) Plc UK Ltd Mott MacDonald Group Ltd Arup Group Ltd MWH Consultants Limited National Grid UK Ltd BAA plc Network Rail Civil Engineering Ltd Northumbrian Water Limited BAM Nuttall Ltd Rail Safety and Standards Board Black & Veatch Ltd Royal Haskoning Bureau Veritas RSK Group Ltd Engineers Limited RWE Npower plc BWB Consulting Ltd Sellafield Ltd Cardiff University Severn Trent Water LLP Sir Robert McAlpine Ltd Environment Agency SKM Enviros Consulting Ltd plc Temple Group Ltd Gatwick Airport Ltd Thames Water Utilities Ltd Geotechnical Consulting Group Tube Lines Golder Associates (Europe) Ltd United Utilities Plc Limited University College London Health & Safety Executive University of Bradford Highways Agency University of Greenwich Homes and Communities Agency University of Reading HR Wallingford Ltd University of Salford Institution of Civil Engineers University of Southampton London Underground Ltd WYG Group (Nottingham Office) Loughborough University January 2013 Ministry of Justice 18 Project funders

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