Design Manual for Urban Roads and Streets

Current Members:

John Lahart Project Management

Padraig Kelly Architecture

Anne Kiernan Architecture

Sean McGrath Engineering

Derek Taylor Engineering and Planning

Jason Taylor Urban Design and Planning

Further Acknowledgements: Peer Review Group: John Devlin, John Martin, Seamus Mac Gearailt and Conor Norton

National Roads Authority, National Transport Authority and Road Safety Authority

Phil Jones Associates

Current Members:

Paul Altman, Stewart LoganDepartment of Housing, Planning and Local Government

John McCarthy, Dominic Mullaney Department of Transport, Tourism and Sport

Gerald CraddockNational Disability Authority

Hugh CreeganNational Transport Authority

Helen HughesTransport Infrastructure Ireland

Tony Reddy Tony Reddy Architecture

Past Members

Tadhg McDonnell Project Management

Eddie Conroy Architecture

Robert Curley Engineering

Paul Hogan Planning

Dominic Molony Engineering

John Stapleton Engineering

Past Members

Martin Colreavy Department of Arts, Heritage and the Gaeltacht

Aileen Doyle, John Martin, Aidan O’ConnorDepartment of the Environment, Community and Local Government

Ciarán Fallon Dublin City Council

Clare Finnegan Department of Transport, Tourism and Sport

ACKNOWLEDGMENTS

The Design Manual for Urban Roads & Streets (DMURS) has been prepared for the Department of Transport, Tourism and Sport and the Department of Housing, Planning and Local Government by a multidisciplinary project team primarily consisting of:

Overseen by a Steering Committee primarily consisting of:

MINISTER’S INTRODUCTION

Ireland’s major towns and cities are now linked by a network of high quality, well planned inter-urban roads. This achievement has resulted in a significant improvement in journey times and contributed to a welcome reduction in road fatalities and injuries as well as greater savings in fuel and lower carbon emissions.

The completion of the National Road network has delivered tangible economic, social and environmental benefits throughout Ireland. It is now timely to build on this progress by re-examining the role and function of streets within our urban areas, where vehicular traffic is most likely to interact with pedestrians and cyclists and where public transport can most effectively and efficiently be planned for and provided.

Better street design in urban areas will facilitate the implementation of policy on sustainable living by achieving a better balance between all modes of transport and road users. It will encourage more people to choose to walk, cycle or use public transport by making the experience safer and more pleasant. It will lower traffic speeds, reduce unnecessary car use and create a built environment that promotes healthy lifestyles and responds more sympathetically to the distinctive nature of individual communities and places.

Leo Varadkar, TDMinister for Transport, Tourism and Sport

Jan O’Sullivan, TDMinister of State, Department of Environment, Community and Local Government with special responsibility for Housing and Planning

Whether travelling to work, school or college or for shopping, social or leisure purposes, improved street design as envisaged in this document will enhance how we go about our business, how we interact with each other and have a positive impact on our enjoyment of the places to and through which we travel.

This Manual offers a holistic approach to the design of urban streets in cities, towns, suburbs and villages in Ireland for the first time and promotes a collaborative and consultative design process. It requires professionals of different disciplines to work together to achieve better street design. We welcome this Manual and look forward to the added value and improvements in quality of life that will be achieved through implementation of this integrated and progressive approach.

PREFACE

It is beyond doubt that the streets of our cities and towns, suburbs and villages, should be safe, attractive and comfortable for all users. As well as cars and other vehicles this encompasses pedestrians, cyclists, and those using public transport. It also includes people of all ages and abilities and is equally relevant to residents and visitors.

As Ireland follows the global trend towards increased urbanisation we must ensure our cities and towns are pleasant, safe and healthy places to live. Any form of movement within densely populated space entails risk. Perception of risk is an important part of road safety. Spaces that ‘feel’ safe for driving are often hazardous places to walk or cycle. These spaces sometimes induce a false sense of safety and a tendency to drive at inappropriate speed. Thus, well intended designers inadvertently transfer risk from motorists to more vulnerable road users.

The desire for safe, attractive and vibrant streets is reflected in a range of existing transport, planning and environmental policies and objectives. These policies and objectives address how neighbourhoods, villages and towns are created and protected. They relate not only to road safety and civil engineering, but also to town planning, urban design, architecture, landscape architecture and conservation.

More significantly, they bear directly on broad societal issues, ranging from economic development, employment, tourism and recreation, through health, crime and security and onto education, social inclusion, energy efficiency and climate change.

In other words, the design of safer, more attractive and vibrant streets, will benefit everyone by generating and sustaining communities and neighbourhoods, with wide ranging economic, social and environmental consequences.

It is significant to note that the evolution of current policy extends back more than a generation. A paper given at a ‘Streets for Living’ Conference in Dublin in 1976 stated:

‘We are expecting from our human settlements the characteristics of streets in order to humanise them, particularly in our residential areas, and yet we have set our designers the task of designing and building and indeed maintaining what are undoubtedly roads…traffic taken in isolation can be a totally destructive force in the formation of human settlements.’1

The above has remained more accurate than ever, but given the extent to which policy and legal frameworks have advanced in recent years, it is now possible to achieve change. Accordingly, this Manual does not seek to set out new policy. It gives effect to existing policy by providing guidance on how to approach the design of urban streets in a more balanced way.

1 Paper entitled The Visual and Social Problems of the Design of Residential Areas Today, Ruairi Quinn, Streets for Living Conference, Dublin 1976.

ABOUT THIS GUIDE

This Manual complements previous advice issued viz:

• Traffic Management Guidelines (2003).

• Smarter Travel (2009).

• Guidelines for Planning Authorities on Sustainable Residential Development in Urban Areas (Cities, Towns and Villages) (2009)

• National Cycle Manual (2011). • Planning Guidelines: Local Area Plans

(2013). DMURS provides guidance relating to the design of urban roads and streets. The Design Manual for Roads and Bridges (DMRB) shall not henceforth apply to urban roads and streets other than in exceptional circumstances. Where those circumstances arise, written approval shall be obtained from the relevant sanctioning authority (as set out in Section 1.3 Application of this Manual).

This document is designed to be universally accessible to all professionals associated with street design. It presents a series of principles, approaches and standards that are necessary to achieve balanced, best practice design outcomes with regard to street networks and individual streets. It does so by presenting these in a structured format, ranging from macro level to micro level considerations.

This document is also designed to respond to the principles of universal design, as outlined in documents such as ‘Building for Everyone, A Universal Design Approach’, published by the Centre for Excellence in Universal Design.

The principles, approaches and standards set out in this Manual are intended for use by suitably qualified and experienced designers who work within the built environment professions. Designers must exercise a duty of care when applying the Manual.

This Manual does not purport to account for every scenario that a designer will encounter, particularly when retrofitting existing streets. Nor can this Manual cover every technical detail. Many matters are left to the professional expertise and judgement of users, while others are covered elsewhere in relevant Irish, British or European standards, in codes of practice and guidelines, many of which are cross-referenced throughout this Manual.

CONTENTS

Chapter 2 makes the case for change and sets out the principles for a new direction that seeks to balance the needs of Place and Movement.

Chapter 1 introduces the goals of the Manual and demonstrates its context within the evolution of Government policy aimed at promoting more sustainable communities.

CHAPTER 2: RE-EXAMINING THE STREET

2.1 The Need for Change2.1.1 The Impact of the Car2.1.2 The Pedestrians Perspective

2.2 The Way Forward2.2.1 ‘Place’ as Part of the Design Equation2.2.2 User Priorities2.2.3 A Balanced Approach

CHAPTER 1: INTRODUCTION

1.1 A Different Perspective

1.2 Policy Background

1.3 Application of this Manual

CHAPTER 4: STREET DESIGN

4.1 Movement, Place and Speed4.1.1 A Balanced Approach to Speed4.1.2 Self-Regulating Streets

4.2 Streetscape4.2.1 Building Height and Street Width4.2.2 Street Trees4.2.3 Active Street Edges4.2.4 Signage and Line Marking4.2.5 Street Furniture4.2.6 Materials and Finishes4.2.7 Planting4.2.8 Historic Contexts

4.3 Pedestrian and Cyclist Environment4.3.1 Footways, Verges and Strips4.3.2 Pedestrian Crossings4.3.3 Corner Radii4.3.4 Pedestrianised and Shared Surfaces4.3.5 Cycle Facilities

4.4 Carriageway Conditions4.4.1 Carriageway Widths4.4.2 Carriageway Surfaces4.4.3 Junction Design4.4.4 Forward Visibility4.4.5 Visibility Splays4.4.6 Alignment and Curvature4.4.7 Horizontal and Vertical Deflections4.4.8 Kerbs4.4.9 On-Street Parking and Loading

Chapter 3 outlines the approaches to the design and management of street networks with the aim of creating better connected places.

CHAPTER 3: STREET NETWORKS

3.1 Integrated Street Networks

3.2 Movement and Place3.2.1 Movement Function3.2.2 Place Context

3.3 Permeability and Legibility3.3.1 Street Layouts3.3.2 Block Sizes3.3.3 Retrofitting3.3.4 Wayfinding

3.4 Management3.4.1 Vehicle Permeability3.4.2 Traffic Congestion3.4.3 Bus Services3.4.4 Relief Roads3.4.5 Noise and Air Pollution

Chapter 4 outlines the approaches and standards applicable to the design of individual streets with regard to context and the promotion of a self-regulating environment.

5. IMPLEMENTATION

5.1 The Challenge Ahead

5.2 A Plan-Led Approach5.2.1 Policy and Plans5.2.2 Development Rationale

5.3 Multidisciplinary Design Process5.3.1 Design Team5.3.2 Process

5.4 Audits5.4.1 Road Safety Audits5.4.2 Quality Audits

Chapter 5 outlines a plan-led, multidisciplinary approach that will facilitate the implementation of the Manual.

APPENDICES

GlossaryBibliographyIndex

CHAPTER 1: INTRODUCTION

The desire for safe, attractive and vibrant streets is reflected in a range of existing environmental policies and objectives.

3May 2019 (Version 1.1)

1. INTRODUCTION

1.1 A Different Perspective

This Manual seeks to address street design within urban areas (i.e. cities, towns and villages). It sets out an integrated design approach. What this means is that the design must be:

a) Influencedbythetypeofplaceinwhich the street is located, and

b) Balancetheneedsofallusers.

AfurtheraimofthisManualistoputwell-designedstreetsattheheartofsustainablecommunities. Well designed streets can createconnectedphysical,socialandtransport networks that promote real alternativestocarjourneys,namelywalking,cyclingorpublictransport.

In preparing this Manual, it was instructive to examineandlearnfromexperienceinIrelandand elsewhere. This alternative requires a shiftinthinkingawayfromrecentlyacceptedpractice approaches toward more sustainable approaches (see Figure 1.1). For example, in the UK, practice has evolved through several iterationsofstreetdesignguidanceinrecentdecades.

InmanycommunitiesthroughoutIrelandit is perceived that some or all vehicular trafficistravellingtoofastandshouldbedirected elsewhere. The impacts are seen asathreattothesafetyofthecommunityandanegativeelementthatdetractsfromtheattractivenessoftheroadorstreetandthecomfortofthoseusingit.Inresponse,itissometimespossibletoinstallatraffic-calmingramp.Sucha‘retrofit’solutionmayslowtraffic,butonlyverylocally.Itdoesn’taddressthebroaderissueofwhatelementsoftheroaddesignorstreetnetworkencourage speeding.

In order to address the overall issue, it is necessarytostartwiththedesignofthestreet environment and street network as a whole.This‘holistic’,design-ledapproachhasbeenappliedsuccessfullyintheUK,muchofEuropeandfurtherafield.Althoughtherearesomegoodindividualexamplesofstreet design in Ireland (see Figure 1.2), there isaneedforagreednationalstreetdesignstandardsspecificto‘urban’areas.

Figure 1.1: This guide will focus on shifting the emphasis of designers, as appropriate, from more conventional approaches that are concerned with the movement of traffic to more sustainable approaches concerned with multi-modal movement and streets as places.

Sustainable Approach

Physical Dimensions Social Dimensions

Mobility Accessibility

Traffic Focus

Large in Scale

People Focus

Compact Urban Form

Forecasting Traffic

Street as a Traffic Conduit

Multi-Model Travel

Street as a Place

Demand Based

Free Flowing

Management Based

Traffic Calmed

Travel Time Minimisation Travel Time Contextualisation

Segregation Greater Integration

Conventional Approach

Design Manual for Urban Roads and Streets4

Streetdesigncanbemoreeffectiveincostandefficiency,slowingtrafficspeeds,through understanding and addressing driverbehaviour.Carefulplace-makingwill protect heritage and tourism potential whilstfacilitatinggrowthandnewuses.Betterqualitypublicrealmwillpromotecivicconfidenceandcanattractstakeholderinvestment,thuscreatingjobs.Encouragingwalkingandcycling,linkedtoeasieraccessforabroadrangeofagesandabilities,willensure liveliness and interaction on streets, therebyincreasingvibrancyandimprovingcommercialandretailactivity.

The cumulative economic, social and environmentalimpactsoftransportchoicesonthedesignofthebuiltenvironmentareoftenoverlooked.Afocusonimprovedstreetdesignwillcontributetobettervalueformoney,socialinclusionandreducedcarbonemissions.

The sustainable urban neighbourhood is diverse,focusedonidentifiablecentres,andwalkable. Streets and roads should join rather than separate places and communities. The sustainable urban neighbourhood provides theprincipalbuildingblockofaviablecommunitywhetheratthescaleofvillage,townorcity.

This Manual recognises the importance ofassigninghigherprioritytopedestriansandcyclists,withoutundulycompromisingvehicle movement, in order to create secure, connectedplacesthatworkforallmembersofthecommunity.Walkingandcyclingwillimprovehealthandwell-beingandwillprovidegreateropportunitiesforinteractionwhich promote neighbourliness and communitygrowth.

ThisManualfocusesonstreetsasattractiveplaces, whether new or existing. It seeks to encourage designs appropriate to context, character and location that can be used safelyandenjoyablybythepublic.

ThisManualisprimarilyintendedforthosebuiltenvironmentprofessions(bothprivateandpubicsectors)concernedwiththedesignofroads or streets in cities, towns and villages. Itisalsorelevanttopoliticians,policymakersandcommunitygroups.Particularemphasisisplacedontheimportanceofcollaborativeworkingandco-ordinateddecision-making.

Figure 1.2: Ballina, Co. Mayo (top), Drogheda, Co. Louth (middle) and Adamstown, Co. Dublin (bottom). This Manual will build upon the many examples of streets which create positive places that serve communities in an inclusive way.


1.2 Policy Background

Nationalplanningandtransportstrategyseekstoachieveahierarchyoftowns,linkedbyefficienttransportnetworks,underpinnedbyeconomicactivityandinvestment.Italso aims to minimise overall travel demand, reduce carbon emissions and reliance on fossilfuels.Centraltothisisthealignmentofspatialplanningandtransportpolicytocontainsuburbansprawl,linkingemploymenttotransportandencouragingmodalshifttomoresustainablemodesoftravel

To support these objectives, street layoutsincities,townsandvillageswillbeinterconnected to encourage walking andcyclingandoffereasyaccesstopublic transport. Compact, denser, more interconnectedlayouts,particularlywhereservedbygoodqualitybusorrailservices,will help to consolidate cities, towns and villagesmakingthemviableforreliablepublictransport.

TheseobjectivesshouldbeunderpinnedbyLocalAreaPlans,StrategicDevelopmentZonePlanningSchemesandLandUseandTransportationStrategies.Theimportanceofretrofittingexistingstreetsandcommunitiesisalso emphasised.

Afurtheraimistoensurecompact,connected neighbourhoods based on street patternsandformsofdevelopmentthatwillmakewalkingandcycling,especiallyforlocaltrips,moreattractive.ThecontextforthepreparationofthisManualissetbythefollowingGovernmentpolicydocuments:


Traffic Management Guidelines (2003)

The Traffic Management Guidelines(TMG),jointlypublishedbytheDepartmentsoftheEnvironmentandTransportandtheDublinTransportationOffice(nowpartoftheNationalTransportAuthorityorNTA),addressawiderangeofissues,intheurbancontext,relatingto street design and parking.

In‘Balancingconflictingprioritiesandmakingtherightchoices’,itisrecognisedthattherearemanydifferentobjectives,modesandusers to be considered in managing the transportnetwork.TheTMGseektopromotemore sustainable alternatives to the private carandacknowledgetheroleofstreetsinurbanareasaslivingspacesthatservemanyfunctionsinadditiontotrafficmovement:

‘Itisonlyinthelastfewdecadesthatthecarhascometodominateeverystreet. Streets are (or ought to be) livingspaces,anintegralpartofthecommunityandthefocusofmanyactivitiesthatlinktogetherpeople’slives.Thewayinwhichstreetsaremanaged and used promotes or discouragesasenseofcommunityand makes them an attractive or unattractive place to live…This imbalancemustbereversedifurbancommunities are to revive and prosper. Plannersandengineersmusttaketheleadinthisprocess.’

Inrelationtothelayoutanddesignofresidentialandcommercialareas,theTMGfurtheracknowledgedeficienciesinthedesign process:

‘...layoutshavebeendictatedbyroadhierarchyconsiderationsbasedaround the movement and parking requirementsofmotorvehicles.Designconsiderationformotorvehicleshascome to dominate the shape and layoutofdevelopments.Thishasoftenbeentothedetrimentofotherroadusersandtherearemanyexampleswheretheroaddesignandspeedoftraffichasdiscouragedpedestrianandcyclemovementbecauseofconcernsoversafety.Ithasalsoledtothecreationofareasthataretoosimilarandlacktheirownsenseoflocalidentity.’

TheGuidelinesrecommendthatnewdevelopments should address these issues, through the development plan and developmentcontrolprocessesandtheyincludesomeusefulsuggestionsinrelationtospecificmatterssuchaspermeabilityandaccess to public transport.

Significantly,theTMGsuggestthatlocalauthorities publish guidance on how new housing and/or commercial developments are to be designed, including ‘guidance ongenerallayoutanddesignofresidential/commercialroadsandfootways/cycleways’.1 AnumberofrelevantUKdesignguidesarereferencedthat‘couldformthebasisforsuchguidance.Theywouldneedsomemodificationtoreflectlocalandnationaldifferencesinlayoutanddesignofhousing,useofmaterials,localparkingandgarageuseetc.toachieveasenseoflocalidentity.’

1 Todate,withtheexceptionofthe Adamstown Street Design Guide (2010)preparedbySouthDublinCountyCouncil,nosuchlocalguidancemanualshave been published.


Guidelines for Planning Authorities on Sustainable Residential Development in Urban Areas (Cities, Towns & Villages) (2009).

ThisguidancedocumentwaspublishedbytheDepartmentoftheEnvironmentandisaccompaniedbytheUrbanDesignManual.ItreplacedtheResidentialDensityGuidelines(1999)andfocusesonsustainableresidentialdevelopment,includingthepromotionoflayoutsthat:

• Prioritisewalking,cyclingandpublictransport, and minimise the need to use cars;

• Areeasytoaccessforallusersandtofindone’swayaround;

• Promotetheefficientuseoflandandofenergy,andminimisegreenhousegasemissions;

• Provideamixoflandusestominimisetransport demand.

Specifically,inrelationtothedesignofresidentialstreets,theGuidelinesreferencethe UK Manual for Streets (2007) and detail principlesthatshouldinfluencethelayoutanddesignofstreetsinresidentialareas.Theseprinciples include:

• Connectivityandpermeability;

• Sustainability:Priorityshouldbegiventotheneedsofwalking,cyclingandpublictransport,andtheneedforcar-bornetripsshould be minimised;

• Safety:Streets,pathsandcycleroutesshouldprovideforsafeaccessbyusersofallagesanddegreesofpersonalmobility;

• Legibility:Itshouldbeeasyforbothresidentsandvisitorstofindtheirwayinthearea; and

• SenseofPlace:Streetsshouldcontributetothecreationofattractiveandlivelymixed-use places.

TheGuidelinesalsoincluderecommendationsinrelationtostreets,‘Frontage-freestreets (such as distributor roads) are not recommended,astheycanbeunsafeforpedestrians(especiallyafterdark)andcanresultinahostileenvironment.’TheGuidelinesfurtherrecognisethat‘mostresidentialstreetscansuccessfullycombinelowtomediumtrafficmovementswithapleasantresidentialsetting,includingon-streetparkingandthedesignofsuchstreetsfromtheoutsetshouldlimittrafficspeedswithintherangeof30-50km/h,withouttheneedtoresorttotheuseofremedialmeasuressuchasspeedramps.’

TheGuidelinesalsomakerecommendationsinrelationtocul-de-sacs(theyshouldnotdominateresidentiallayouts);sharedpriority‘homezones’andpedestrianandtrafficsafety.Thereisalsoausefulseriesofurbandesigncheckliststhatincludethefollowinginrelation to street design:

• Doesthedesignofresidentialstreetsstriketherightbalancebetweenthedifferentfunctionsofthestreet,includinga‘senseofplace’.

• Will the development:

- prioritisepublictransport,cyclingandwalking,anddissuadetheuseofcars?

- ensureaccessibilityforeveryone,includingpeoplewithdisabilities?

- includemeasurestoensuresatisfactorystandardsofpersonalsafetyandtrafficsafetywithintheneighbourhood?

• Willtheplanensureacompactandeasilywalkableformofdevelopmentthatwillmakewalkingandcycling,especiallyforlocal trips, more attractive than using the car?

• Has the design sought, where possible, tocreatechildandpedestrian-friendlycar-freeareas,especiallyinhigherdensityschemes,throughthecarefullocationofaccessstreetsandparkingareas?


Smarter Travel - A Sustainable Transport FutureA New Transport Policy for Ireland 2009-2020

ThisdocumentwaspublishedbytheDepartmentofTransport.Itsetsoutfivekeygoalsasfollows:

(i) to reduce overall travel demand;

(ii) tomaximisetheefficiencyofthe transport network;

(iii) toreducerelianceonfossilfuels;

(iv) to reduce transport emissions; and

(v) toimproveaccessibilitytopublic transport.

Toachievethesegoals,keytargetsincludeobjectivesthatfuturepopulationandemploymentgrowthwillpredominantlytakeplaceinsustainablecompactforms,whichreducetheneedtotravelforemploymentand services and alternatives such as walking, cyclingandpublictransportwillbesupportedand provided to the extent that these will rise to55%oftotalcommuterjourneystowork.

Further to outlining actions to reduce travel demand, it is targeted that in Ireland around 200,000peoplewillswitchtocyclingandwalkingby2020.

Thedocumentspecificallyidentifiesthepreparationofa‘DesignManualforStreets’,‘which will outline practical design measures to support and encourage more sustainable travelpatternsinurbanareas’,askeyactionsto encourage smarter travel.

Thedocumentdetailsarangeof‘Actions’inrelationtotheintegrationoflanduseplanningandtransportpolicy.Itisrecognisedthatthiscannotbeachievedsolelyinrelationtonewdevelopmentandthesignificanceofretrofittingishighlighted:

‘We will require local authorities to prepareplanstoretrofitareastowardscreating sustainable neighbourhoods sothatwalkingandcyclingcanbethebestoptionsforlocaltrips,forexampletoreachlocalfacilitiessuchasshopsandschools’.

The document includes a vision to create a strongcyclingcultureinIrelandandensurethat all cities, towns and villages will be cycling-friendlyandthatcyclingwillbeapreferredwaytogetabout,especiallyforshort trips. There is also a commitment to creating a culture in Ireland that encourages peopletowalkasamatterofroutine.Measures to ensure this include:

• Reprioritisingtrafficsignalstofavourpedestrians,insteadofvehicles;

• Reducing waiting times and crossing distances at junctions;

• Ensuringthat30km/hzonesaredesignated in central urban areas which also continue to accommodate motorised traffic;

• Wideningfootpathswheretherearehighpedestrianflows,particularlyclosetopublic transport nodes;

• Clearingfootpathsofunnecessarystreetfurniture,e.g.rationalisationofsignagepoles etc.;

• Improvingthesurfacequalityoffootpaths;

• Providingappropriatelydesignedsafe,well-lit,direct,continuousroutes.


Planning Guidelines: Local Area Plans 2013

This guidance document and its companion guide, the Manual for Local Area Plans (2013), waspublishedbytheDepartmentoftheEnvironmentinJune 2013.

TheLAPguidelinessetouttherangeofrequirementsforthemakingofLAPs,includingtheircontent.Manyoftheserequirementsareconcerned with placemaking and the design ofstreetsandstreetnetworks,including:

‘improvingthepublicdomainbyprovidingactivefrontagetoallpublicspaces and routes, thus promoting streets which encourage pedestrian activityandaresaferbybenefitingfrompassivesurveillance’.

‘providing compact, walkable neighbourhoods incorporating a varietyofhousetypeswithmixedtenure’.

‘designing in active streets and designingoutanti-socialbehaviourthrough urban masterplanning, encouraginggoodmixtureofusesandadaptabilityofbuildings’.

‘measures to encourage local people toadopthealthier,smarterwaystotravel around their local communities, especiallywalkingandcycling’

‘pedestrians,cyclistsandusersofothermodesoftransportthatinvolvephysicalactivityaregiventhehighestpriorityintransportandmobilitystrategies,policiesandobjectives’

The Manual for Local Area Plans provides more detailed measures to achieve these goals. In relation to street design, this includes:

‘Create or enhance a distinctive hierarchyofstreets,spacesandlandscapes within an integrated structure’.

‘Ensurepriorityforpedestrians,cyclistsandpublictransport’.

‘Setoutthenatureandhierarchiesofpublictransport’.

‘Optimiseareasofhighaccessibilitytopublictransportintermsofdensityandintensityofuse’.

‘Promoteshared,safemovementroutesforallusersandavoidduplicationorseparationofmainmovementroutes’.

‘Set out the general movement functionofroutesandspaceswithintheroutehierarchy’.


1.3 Application of this Manual

The principles, approaches and standards setoutinthisManualapplytothedesignofall urban roads and streets (that is streets and roadswithaspeedlimitof60km/horless),except:

(a) Motorways.

(b) In exceptional circumstances, certain urban roads and streets with the written consentofSanctioningAuthorities.2

ThisManualcannotaccountforeveryscenario(particularlywhenretrofittingexistingstreets)thatadesignermayface,theapplicationofprinciples,approachesandstandards contained herein requires a degree offlexibility.Thisisprovidedtodesigners,withinalimitedframework,viatheuseofthefollowingterminology:

ForthepurposesofthisManual:

• ‘Shall’ or ‘must’ indicates that a particular requirementismandatory;

• ‘Should’ indicates a recommendation. Wheredesignersfailtomeetarecommendation,theymustclearlydocumentthereasonsastowhyandproposeaseriesofmitigationorcompensation measures.

• ‘May’indicatesaclarification,optionoralternativecourseofaction.

2 Sanctioning Authorities include:

(i) TransportInfrastructureIrelandinrespectofurbannational roads. TII shall consult with the NTA in respect ofsuchroadswhichliewithintheGreaterDublinArea

(ii) TheNationalTransportAuthorityinrespectofurbannon-nationalroadswithintheGreaterDublinArea.

(iii) TheDepartmentofTransport,TourismandSportinrespectofurbannon-nationalroads.

TheManualintroducesasetofprinciples,approachesandstandardsnecessarytoachieve best practice in urban roads and street design. Implementationoftheprinciplesapproaches and standards will be achieved through actions at national and local level.

At the national level:

1. TheDepartmentofTransportTourismandSport(DTTS)andtheDepartmentEnvironment,CommunityandLocalGovernment(DECLG)introducedthisManualasakeystepinimplementingthepoliciesonpromotingtheuseofmoresustainable transportation proposed in Smarter Travel (2009) and the policies on sustainable living contained in the Guidelines on Sustainable Residential Development in Urban Areas (2009).

2. DTTSandtheDepartmentofHousing,

PlanningandLocalGovernment(DHPLG,formerlyDepartmentofEnvironment,CommunityandLocalGovernment)willwork with local authorities in assisting with technicalaspectsoftheimplementationoftheManualonanon-goingbasis,learningfromexperiencewithinIrelandandinternationally.

Atcityandcountylevel:

1. Localauthoritiesshallfacilitatetheimplementationoftheprinciples,approaches and standards to road and street design set out in the Manual in carryingouttheirdevelopmentplanningfunctionsunderthePlanningCode.

2. CityandCountydevelopmentplansshallreferencethisManualinordertofacilitatetheimplementationofthepoliciesforsustainablelivingcontainedinthe Guidelines on Sustainable Residential Development in Urban Areas (2009). Local AreaPlansandalsoothernon-statutoryplansshouldalsoreferencetheprinciples,approaches and standards within this Manual, where appropriate.


3. Localauthoritiesshouldfacilitatetheadoptionofthemultidisciplinaryapproachto consultation where appropriate and shall use the relevant standards in the Manual when assessing planning applications which relate to or impact on urban roads and streets.

4. Inthecaseofapplicationsforplanningpermission and development consents to planningauthoritiesandAnBordPleanála,applicants and their agents shall:

• Utilise, as appropriate, the multidisciplinarydesignteamsadvisedin this Manual.

• Carefullyexaminetheirdevelopmentproposals which relate to or impact on urban roads and streets to ensure that theyareconsistentasfarasispracticalwith the principles, approaches and designstandardsofthisManual.

• Engagewithplanningauthoritiesatanearlystage,utilisingthearrangementsforpre-planningapplicationconsultationwithregardtoanyissuethatmayariseinrelationtotheapplicationofdesignapproachessetout in the Manual.

5.Inthecaseoflocalauthorityowndevelopmentinrelationtothedesignofurban roads, streets or networks,3 local authorities shall:

• Facilitate as appropriate the multidisciplinarydesignteamsadvisedin the Manual.

• Ensurethattheprinciples,approachesandstandardsofthisManualareapplied as appropriate.

3 IncludingdevelopmentmadeunderPart8ofthePlanningandDevelopmentRegulations,2001.

CHAPTER 2: RE-EXAMINING THE STREET

The creation of walkable, cycleable and public transport orientated communities require that designers re-examine the way streets are designed in order to meet the needs of all users.


2. RE-EXAMINING THE STREET

2.1 The Need for Change

Smarter Travel (2009)demonstratesthatiftravel trends within Ireland are not changed, congestion will increase, transport emissions will grow, economic competitiveness deteriorate,andtheoverallqualityoflifedecline. Targets are set out to be achieved by2020.1 These include:

• Thetotalshareofcarcommutingtobereducedto45%;

• Walking,cyclingandpublictransporttoachievea55%shareofjourneystowork,withcyclingcomprising10%;

• Totalkilometrestravelledbythecarfleetin2020nottoincreasesignificantlyfrom2009levels.

Table 2.1 illustrates how people within Ireland travel to work. This table serves to highlight the scaleofthechallengeahead.Irelandishighlycar dependent when compared with our Europeanneighbours.

1 RefertoChapter3- Smarter Travel (2009).

Location/Travel Mode

Vehicle 72% 55% 72% 72% 68% 76% 75% 66% 81%

On Foot 10% 14% 14% 15% 14% 14% 12% 13% 4%

Bicycle 2% 6% 2% 2% 5% 2% 1% 3% 0.5%

Bus, mini bus or coach

5% 13% 7% 4% 6% 3% 3% 8% 1%

Train,Dartor LUAS

3% 7% 0.4% 0.2% 0.4% 0.2% 3% 4% 0.5%

Table 2.1: Mode of travel to work within the State broken down by urban area (source Census 2011). Note: vehicle includes car, van, lorry or motorcycle as driver or passenger.

TherehavebeensignificantchangesthroughoutEuropeinrecognitionoftheinfluencethedesignofstreetsandstreetnetworks have on travel patterns. Smarter Travel (2009) recognises that unless streets aredesignedtobetterfacilitateandprioritisealternativemodesoftransport(tothecar),thetargets contained therein will not be met.

Section 2.1.1 below examines the relationship betweentheplaceandmovementfunctionsofastreet,providesareviewofconventionaldesign practices and sets out an alternative, more sustainable approach.

Dublincity

and suburbs

Corkcity

and suburbs

Limerickcity

and suburbs

Galw

aycityand

suburbs

Waterford

cityand

suburbs

All other urban

areas

All urban areas

All rural areas

Ireland (state)


2.1.1 The Impact of the Car

Thecarhasasignificantimpactonhowstreetnetworks and streets are designed and how people interact with them. The relationship between cars and people can be illustrated viafourdistinctmodels(seeFigure2.1):

• Thefirstmodeliswheretrafficandpeopleare segregated and the car is dominant.

• The second model is where the car and peoplearesegregatedfromeachother.

• Thethirdmodeliswheretrafficandpeoplemix, although on a more equitable basis.

• Thefourthmodeliswherethecarisexcluded altogether.

Conventional design approaches in Ireland arelargelybasedontheapplicationofthefirstandsecondmodels.Pedestrianandvehicularmovementaresegregatedfromeachotheronthebasisthatahigherqualityofservicecouldbedeliveredforeachmode.

Conventional design approaches within IrelandareheavilyinfluencedbytheUKpublication Traffic in Towns (1963)ortheBuchanan Report,asitbecamewidelyknown.UtilisingtheRadburnprinciplesofsegregation,the Buchanan Report envisaged the creation ofahighlyorderedandstructuredstreetnetworkthatseparateddifferentmodesoftravel (see Figure 2.2).

The Buchanan Report was advanced in the UKbythepublicationofRoads in Urban Areas (1966).TheDocumentproclaimedthat‘segregationshouldbethekeynoteofmodernroaddesign’and‘shouldbeappliedasfaraspracticalornecessary’.Itrecommended:

• Thesegregationofmotorvehiclesonthebasisofpurpose,destinationortype.

• Thesegregationofmotorvehiclesfromvulnerable road users (e.g. pedestrians andcyclists).

Figure 2.1: Four models of road design, adapted from Jan Gehl within Life Between Buildings (1971), illustrating the relationship between cars and people within a road or street.

3. INTEGRATION

1. CAR DOMINANCE

2. SEGREGATION

4. CAR EXCLUSION


• Theprovisionof‘distributorroads’for‘thefreeflowoftrafficatreasonablespeed’alongwhichaccessandfrontagedevelopmentwasfullyorpartiallyrestricted.

• Thecreationof‘neighbourhoodcells’thatrestrictthemovementofthroughtraffic.

• Thesegregationofmovingvehiclesfromparkedvehiclesprimarilythroughrestrictionsonon-streetparking.

These recommendations had a major influenceinIrelandasdesignersbecameincreasinglyfocusedontrafficflowandcapacity.Oneofthemostexpansiveexamplesofthisinfluencecanbeseeninthe Dublin Transportation Strategy (1971) whichsoughttoreshapeinnerDublinintoafunctionalsystemofone-waystreetsystems,ringroadsandmotorwaysinordertorelievecongestion(seeFigure2.3).Whilstsuchagrandschemewasneverrealised,manystreetswereincrementallychangedovertime(includingconversiontoone-waysystems)toincreasecapacityandreducecongestion.

Figure 2.2: Images from the highly influential Traffic in Towns which drew upon the modernist vision of a highly ordered and efficient road network where users were vertically segregated by type (image source: Traffic in Towns (1963)).

Figure 2.3: Dublin Transport Strategy (1971). Although the scale of vision was never realised many aspects such as one-way traffic systems were implemented.


Theinfluenceof Traffic in Towns (1963)isparticularlyevidentinthedesignofnewresidentialareasdevelopedfromthe1960s(see Figure 2.4):

• Throughtrafficischannelledalongaseriesofdistributorroadsthataredesignedwithminimalinterruptiontotheflowoftraffic(i.e.frontagefree,restrictedpointsofaccess, no parking).

• Access to the neighbourhood cell, and movementwithinit,ishighlyrestricted.Thisisenforcedbydendriticstreetnetworksthatconsistofalargeproportionofcul-de-sacs.

Figure 2.4: Example of a residential community designed according to the keynote principles of segregated street networks. 1) Distributor roads are designed to facilitate free flowing traffic and provide access to 2) neighbourhood cells. Movement through the cell enforced via a dendritic street layout of 3) cul-de-sacs that spread out like the branches of a tree (base image source: Google Maps).

1

2

3

1

2

3

Somesegregatedstreetnetworksmayhavebenefitswithregardto:

• Separatingslowerandfastermodesoftransport.

• Thewidespreadapplicationofcul-de-sacsmaybepopularbecauseoftheirperceivedsafetyandrelativelytrafficfreeenvironment(ifshortinlength).

• Largecarfreeareasmayshelterpedestriansandcyclistsfromtraffic.

However, segregated design solutions (particularlywherethecarisdominant)havetendedtofailasplaces,increasecardependencyandreducepedestriansandcyclistactivity.

Thefollowingreviewofconventionaldesignoutcomeshasaparticularfocusonthepedestrian environment as well as the street as aplace.Manyofthescenariosdepictedarealsoofrelevancetocyclists,withmanysimilarissues highlighted throughout the National Cycle Manual (2011).


2.1.2 The Pedestrian Perspective

Connectivity

Acoreobjectiveofasegregatedapproachtostreetdesignisthecreationofahighlyfunctionaltrafficnetwork.Thisapproachhasleftmanycommunitiesdisconnectedandhasplacedsignificantlimitationsonsustainableformsoftransportation.Theconnectivity(andlegibility)problemswhicharisefromdendriticstreetlayoutsareillustratedinFigure2.5,wherewalking distances are increased, route choice ishighlylimitedandusershavetonavigatea complicated street network. Research has shown,thatalackofconnectivityisoneofthekeyfactorsthatdiscouragepeoplefromwalking.2

Thehighlysegregateddesignofdistributorroads also presents a major barrier that creates severance between adjoining communities(seeFigure2.6).Thisoccursbecausephysicalrestrictionsinaccessareenforcedbycontinuouswallsandfencesputin place to prevent pedestrian access. Where accessisproposed,safetyconcernsareoftenraisedbecauseofthefastmoving/freeflowingnatureoftheseroads,evenwheretheremaybemajorbenefitsintermsofaccesstoservices(see Figure 2.7).

2 RefertoUnderstanding Walking and Cycling (2011).

Figure 2.5: A typical example of a residential area constructed in accordance with the principles of segregation. Walking and cycling permeability is restricted to the point that the two neighbouring houses shown back to back are up to 4km walking distance apart.

Figure 2.6: Distributor Road which creates severance between communities. The road is designed to minimise any disruption to vehicle movement by restricting the number of junctions and pedestrian access (through the use of walls and fences). The road is also frontage free, eliminating the need for driveway access to individual properties.


Connectivityandlegibilityissuesalsooccurata more localised scale where the movement oftrafficisgivenpriorityoverthatofpedestrians.Pedestriansoftenhavetowalklong distances to designated crossing points. Largerjunctionscanalsobedifficulttonavigateandsignificantlydelayjourneytimes.Manylargejunctionscorralpedestrianmovement(andinsomecasescyclists)awayfromdesirelines,usingguardrails,increasingtheamountoftimeittakestocrossasusersnavigateanumberofindividuallysignalisedcrossings(seeFigure2.8).

Figure 2.8: Examples of a junctions designed to minimise vehicle delays which significantly increase crossing times for pedestrians. Pedestrian desire lines (represented by the yellow line) are diverted through a series of separate crossings (represented by the red line). The top example can take pedestrians as long as 5 minutes to navigate.

Figure 2.7: Example of a ‘neighbourhood cell’ located within a ‘distributor road’ network. A long fence separates the Cell from the Distributor Road. A number of openings in the fence were initially planned to provide access to bus stops. These were removed at the request of residents due to safety concerns, significantly increasing walking distances to bus stops (base image source: www.bing.com/maps).

530m increase in walking distance to bus stops

380m increase in walking distance to bus stops


Comfort

Pedestriansaresometimesmarginalisedalongthe street edges so that greater space can be providedwithinthestreetreservetofacilitatevehiclemovement.Thisoccursinanumberofways:

• Narrowfootpathssqueezepedestrianstogetheranddonotleavesufficientroomforpeopletopass.

• Footpaths become cluttered with poles and guardrails that obstruct and constrain pedestrian movement and create visual clutter.

• Footpaths are lined with blank walls and fencesthatrestrictpassivesurveillanceandmakepedestriansfeelisolatedandvulnerable.

These elements can combine to obstruct vulnerableusersandattimesitisnecessaryforthemmoveontooutontocyclepaths/lanesand/orvehicularcarriagewaysinordertoprogressalongthestreet(seeFigures2.9-2.11).Alackofon-streetparkingfacilitiescanalsocontributetotheobstructionoffootpathsandcyclepaths/lanes.Wheredemandforon-streetparkingexistsandisnotcateredfor,driversroutinelykerbmountandparkonfootpathsandcyclelanes(seeFigure2.12).

Figure 2.11: Pedestrians have been marginalised along the street edge and have their path obstructed in order to provide additional width to the vehicular carriageway and space for signage.

Figure 2.9: Footpath widths are inadequate, forcing pedestrians on to the carriageway, however, the width of the vehicular lane is in excess of what is generally required.

Figure 2.10: Guardrails can create a hazard for cyclists, reduce footpath widths and give rise to feelings of constraint and restriction to pedestrians.


Figure 2.13: Example of a street that is hostile to pedestrians and cyclists (especially after dark). The unwillingness of people to interact with this type of environment will serve to undermine the viability of public transport services.

AsrecognisedbytheGuidelines for Sustainable Residential Development in Urban Areas (2009),thedesignofroadsoftenresultsinanenvironmentthatishostileforpedestrians(especiallyafterdark).3 Blank walls and fencesrestrictsurveillanceandmovement.Ifpedestriansfeelisolatedwithinastreetbecauseofitscharacteristics,theyareunlikelytouseit,areunlikelytoavailoftheserviceswithinitandconsequentlywillbecomemorecardependent(seeFigure2.13).Researchhasshownthatalackofactivityandsurveillanceonstreetsisoneofthekeyfactorsthatdiscouragepeoplefromwalking.4

Safety

ManyoftheexamplesinFigures2.5to2.13aredesignedtoeliminaterisk,promotefree-flowingconditionsfortrafficandmakestreetssafer.Bylimitingelementssuchasjunctionsandon-streetcarparking,thenumberofpotentialvehiculartrafficconflicts/stoppagesis reduced. Clearer sightlines and wide carriagewaysalsoallowforgreaterdriverreaction time/error correction. Whilst this approach is sensible on isolated roads, within urban areas it can be counter productive as itmaytransferrisktomorevulnerableusers.Researchhasfoundthat:5

• The speed at which drivers travel isprincipallyinfluencedbythecharacteristicsofthestreetenvironment(see Figure 2.14).

3 RefertoSection3.18oftheGuidelines for Sustainable Residential Development in Urban Areas (2009).

4 RefertoUnderstanding Cycling and Walking (2011). 5 RefertoDesigns for Life: Learning from Best Practice

Streetscape Design (2007).

GO FASTER!! SHOW CAUTION!!

Figure 2.14. The elimination of access and frontage along roads (top) was introduced to reduce risk, but it serves to encourage speeding.

Figure 2.12: If on-street parking is not provided, particularly for visitors, it can lead to poor parking behaviour from drivers who kerb mount and park on footpaths/cycle lanes.


Figure 2.16: Measures which divert and/or delay pedestrians may reduce safety as pedestrians walk/cross in locations which vehicles may not anticipate.

• Ifthedesignofastreetcreatestheperceptionthatitissafetotravelathigherspeedsdriverswilldoso,evenifthisconflictswiththepostedspeedlimit.

Byeliminatingriskandpromotingfree-flowingconditions,driversfeelmoreinclinedtodriveathigherspeeds.Furthermoreifspeedlimitsare perceived as not being appropriate to the environment, it can undermine the speed limitsystemasawhole.6 The extent to which speeding in urban areas is a problem has beenidentifiedinsuccessivesurveyscarriedoutbytheRoadSafetyAuthority,with3outof5driversonurbanstreetsdrivinginexcessofthe posted speed limit.7

The Buchanan Report concluded that pedestriansandvehicleswere‘fundamentallyincompatible’andthatsegregationwouldleadtoasaferroadenvironmentforallusers.However,theenvisagedsegregationofthemotorvehicleandpedestrianisnotfeasiblein an urban environment. It is inevitable that pedestrians and vehicles will interact inurbanenvironments.Bycreatinglarger,free-flowingroadswhichprioritisevehiclemovement, where this interaction occurs it is likelytohappenatamuchhigherspeed,thusincreasingtheseverityofanaccident(seeFigure2.15).

Pedestrianshavelittletolerancefordelayandstudieshavefoundthatsignificantnumbersofpedestrianswillnotcomplywiththedetour/delaycreatedbydiversions,suchasthoseenforcedbyguardrails.8Pedestrianstendtofollowdesirelines(i.e.taketheshortestroute),evenifthisconflictswiththelocationofformalcrossings and pedestrian control measures (seeFigure2.16).Theuseofguardrailsmaybe counter productive as:9

• Itmayincreasevehiclespeedsandaggressive driver behaviour.

6 RefertoCircular RST 02/2011 Guidelines for the Setting of Special Speed Limits (2010).

7 Refertothe RSA Free Speed Survey (2008),(2009)and(2011).

8 RefertotheUKParliamentInquiryintoWalking in Towns and Cities presentedtotheEuropeanTransportConference(2011).

9 Thereareseveralpublicationsthatfurtherdiscusstheuseofguardrails,includingSection4.4ofthe National Cycle Manual (2011);UKDepartmentforTransportLocal Transport Note 2/09 Pedestrian Guardrails (2008);Guidance on the Assessment of Pedestrian Guardrail (2012)andSection12.4oftheManual for Streets 2 (2010).

Figure 2.15: Large freer flowing roads and junctions may result in pedestrians taking greater risks in front of faster moving traffic.


• Createafalsesenseofsafetyforbothdriversandpedestrians(guardrailswillonlystopvehiclestravellingatverylowspeeds).

• Blockintervisibilitybetweendriversandchildren.

• Resultinpedestrians/cyclistsbeingtrappedonthecarriagewayorfoundinlocationsthatarenotanticipatedbydrivers.

• Reducethewidthandcapacityoffootwaysandcrossings.

• Createacollisionhazardforcyclistswherebuiltincloseproximitytocyclelanes.10

Updesigning

Manyoftheissueshighlightedabovehavebeenexacerbatedbyaprocessof‘updesigning’,whereroadsaredesignedtostandardsinexcessoftheirmovementfunction.Thisoftenoccursdueto:

• TheinappropriateapplicationoftheNational Roads Authority Design Manual for Roads and Bridges(NRADMRB)onstreets and roads in urban areas.11

• Cateringfortheeaseofmovementof

largevehicles,whichonlyoccasionallyfrequentaroad/street.

• Enablinggreatercapacityandvehicleflowbasedonexcessivedemandforecastsand/or the assumption that private vehicle usage will increase unabated.

Thecontinuedassumptionofgrowthinprivatevehicleusageisnotsustainableandiscontraryto the targets contained within Smarter Travel (2009). Updesigning also places a significantfinancialburden(bothcapitalandmaintenance) on local authorities (see Figure 2.17). These outcomes represent poor value formoneyandasimpler,moreintegratedapproach can achieve advantages in terms ofsustainability,placemakingandtrafficmovement. 10 RefertoSection4.4.1.3ofthe National Cycle Manual

(2011).11 TheNRADMRBwasprimarilyintendedforuseon

roadsofnational/regionalimportance.Suchroadsgenerallycarrysignificantvolumesoftrafficathigherspeedsoverlongerdistances.NRATD9oftheNRADMRBhasbeensupersededbytheTIIpublicationDN-GEO-03031RuralRoadLinkDesign(2017).

Figure 2.17: Examples of updesigning which provide little cost benefit. From top to bottom, large splayed junction, complex junctions, ramps on wide carriageways, noise walls and repetitive signage.

1

2

3 4 5 6


2.2 The Way Forward

Governmentpolicies(refertoSection1.2PolicyBackground)requireashiftawayfromconventional design solutions toward those whichprioritisesustainablemodesoftransport,safeguardvulnerableusersandpromoteasenseofplace.Theapproachrequiredtoachievetheseoutcomeswillbeprincipallybasedtheapplicationofamoreintegratedmodelofstreetdesign,wherereal and perceived barriers to movement are removed to promote more equitable interaction betweenusersinasafeandtrafficcalmedenvironment.

Integrated approaches incorporate elements ofurbandesignandlandscapingthatinstinctivelyalterbehaviour,thusreducingthenecessityformoreconventionalmeasures(suchasphysicalbarriersandtheroadgeometry)alonetomanagebehaviour.Theattractionofthisapproachisthatitcreatesanewdynamicanda‘win-win’scenariowhere:

• Street networks are simpler in structure (morelegible)withhigherlevelsofconnectivity(morepermeable)thusreducing travels distances.

• Higherqualitystreetenvironmentsattractpedestriansandcyclists,promotingtheuseofmoresustainableformsoftransport.

• Self-regulatingstreetsmanagedriverbehaviourandcalmtraffic,promotingsaferstreets.

• Streets and junctions are more compact, providingbettervalueformoney.

There are those measures associated with segregationthatwillremainakeycomponentofstreetdesign.Thekeytobestpracticestreet design is to promote the street as a placethatappropriatelybalancesthelevelofsegregationandintegrationthatoccurwithinit(seeFigure2.18).Sections2.2.1-2.2.3outlinethedefiningfactorsforachievingbestpracticestreetdesign,includingfourdesignprinciplesfundamentaltotheimplementationofamoresustainableapproach. Figure 2.18: Examples of busy streets and

junctions with a high place value where the degree of segregation decreases/integration increases (from top to bottom) utilising a variety of design techniques that increase pedestrian/cyclist mobility and slow vehicles.

Ashford Ring Road, Ashford, UK

Exhibition Road, London (UK)

O’Connell Street, Dublin

Dorset Street, Dublin


2.2.1 ‘Place’ as Part of the Design Equation

Designersmustbroadenthescopeofissuesthat are considered throughout the design process.Whilstthemovementoftrafficisstillakeyissue,thereareseveralothers,includingthe‘senseofplace’,whichareofcoresignificancetothecreationofsafeandmoreintegrated street designs (see Figure 2.19).12

Theelementsofplacecanbedifficulttodefineastheyoftenrelatetothe‘feel’ofa particular area. More tangible elements ofplacecanbemeasuredandrelatetoconnectivity,thequalityofthebuiltenvironment, how buildings and spaces interactwitheachotherandthelevelsofpedestrianactivitythatoccur. These tangible orquantifiableelementsofastreethighlightfourinterlinkedcharacteristicsthatinfluencethesenseofplacewithinastreet(seeFigure2.20):

Connectivity

Thecreationofvibrantandactiveplacesrequirespedestrianactivity.Thisinturnrequires walkable street networks that canbeeasilynavigatedandarewellconnected.13

12 ReferalsotoSection2.2.1oftheUKManual for Streets (2007).

13 ReferalsototheSection01ofthe Urban Design Manual (2009),whichnotesthatsuccessfulplacestend to be those that are the most well connected.

Figure 2.19: The most fundamental aspect of the creation of a sustainable street network is that designers clearly recognise that streets have both a place and movement function, so that streets are connected, enclosed, fronted onto and promote pedestrian and cyclist activity

Poor integration of place and movement function

Better integration of place and movement function

Enclosure

Asenseofenclosurespatiallydefinesstreets and creates a more intimate and supervised environment. A sense ofenclosureisachievedbyorientatingbuildings toward the street and placing themalongitsedge.Theuseofstreettreescanalsoenhancethefeelingofenclosure.

Active Edge

Anactivefrontageenlivenstheedgeofthestreetcreatingamoreinterestingand engaging environment. An active frontageisachievedwithfrequententrances and openings that ensure the street is overlooked and generate pedestrianactivityaspeoplecomeandgofrombuildings.


ENCLOSURE

ACTIVE EDGE

PEDESTRIAN FACILITIES/ACTIVITY

Figure 2.20: The key characteristics of the street that influence its sense of place. A safe, attractive and comfortable pedestrian environment requires all of these elements.

CONNECTIVITY

KEY CHARACTERISTICS OF PLACE BASED STREET DESIGN

Pedestrian Activity/Facilities

Thesenseofintimacy,interestandoverlookingthatiscreatedbyastreetthatisenclosedandlinedwithactivefrontagesenhancesapedestrian’sfeelingofsecurityandwell-being.Goodpedestrianfacilities(suchaswidefootpathsandwelldesignedcrossings) also make walking a more convenient and pleasurable experience thatwillfurtherencouragepedestrianactivity.

Thesefourcharacteristicsrepresentthebasicmeasures that should be established in order tocreatepeoplefriendlystreetsthatfacilitatemore sustainable neighbourhoods.


2.2.2 User Priorities

To encourage more sustainable travel patternsandsaferstreets,designersmustplacepedestriansatthetopoftheuserhierarchy(seeFigure2.21).Walkingisthemostsustainableformoftransport.Furthermore,alljourneysbeginandendonfoot.Byprioritisingdesignforpedestriansfirst,thenumberofshortjourneystakenbycarcanbereducedandpublic transport made more accessible. The needformorewalkablecommunitiesisalsoanissueofsocialequityasitisthepoorestandmostvulnerableinsociety,includingchildren,theelderlyandthedisabledforwhomcartravelislessofanoption.ResearchfromtheUK has shown that it is these groups who are disproportionatelyaffectedbythethreatofaccident,communityseveranceandthelossofsocialcohesion.14

Designingforcyclistsmustalsobegivenahighpriority.Tripsbybicyclehavethepotentialto replace motor vehicles as an alternative meansoftransportforshorttomediumrangetrips (and in some cases longer range trips). Cyclingalsopromotesahealthylifestyle.Advances have been made in this regard with thepublicationoftheNational Cycle Manual (2011).

WithinIrelanditisthebusthatprimarilycatersformediumtolongrangejourneysforthosewhodon’tdrivethoughnecessityorconvenience.AsnotedbySmarter Travel (2009),commuterswillonlybegintoconsiderashiftfromcartobustransportwhentheadvantagesofthebusaregreaterthanthoseofthecar.Themovementofbusesshouldbeprioritised over other motorised vehicles.

Placingprivatemotorvehiclesatthebottomoftheuserhierarchyshouldnotbeinterpretedasananti-carstance.Peoplewillalwaysbeattractedtocarswheretheyareaconvenientandflexibleoptionandformanyusersitiscurrentlytheironlyviableoptionformediumtolongerdistancejourneys.Thekeyissueisoneofbalance,andtheneedsofthecarshouldnolongertakepriorityovertheneedsofotherusersorthevalueofplace.

14 ReferalsotoUK Fairness in Transport: Finding an alternative to car dependency (2011).

Figure 2.21: User hierarchy that promotes and prioritises sustainable forms of transportation

1. PEDESTRIANS

2. CYCLISTS

3. PUBLIC TRANSPORT

4. PRIVATE MOTOR VEHICLES

CONSIDER FIRST

CONSIDER LAST


2.2.3 A Balanced Approach (Key Design Principles)

Toguideamoreplace-based/integratedapproach to road and street design, designers musthaveregardtothefourcoreprinciplespresented below:

MULTI-FUNCTIONAL STREETSCONNECTED NETWORKS

Design Principle 1:

To support the creation of integrated street networks which promote higher levels of permeability and legibility for all users, and in particular more sustainable forms of transport.

Chapter 3 ofthisManualisconcernedwiththecreationandmanagementofpermeableandlegible street networks.

Design Principle 2:

The promotion of multi-functional, place- based streets that balance the needs of all users within a self-regulating environment.

Chapter 4ofthisManualisconcernedwiththecreationofself-regulatingstreetsthatcaterforthevariousplaceandmovementfunctionsofa street.


PEDESTRIAN FOCUS MULTIDISCIPLINARY APPROACH

Design Principle 3:

The quality of the street is measured by the quality of the pedestrian environment.

Chapter 4ofthisManualalsoprovidesdesignstandardsforthecreationofasafe,comfortableandattractivepedestrianenvironment.

Design Principle 4:

Greater communication and co-operation between design professionals through the promotion of a plan-led, multidisciplinary approach to design.

Chapter 5ofthisManualisconcernedwiththeimplementationofamoreintegratedapproach to street design.

CHAPTER 3: STREET NETWORKS

Street Networks should be designed to maximise connectivity between destinations to promote higher levels of permeability and legibility for all users, in particular more sustainable forms of transport. This will allow people to move from place to place in a direct manner with greater route choice.


3.0 STREET NETWORKS

3.1 Integrated Street Networks

Sustainable neighbourhoods are areas whereanefficientuseofland,highqualityurbandesignandeffectiveintegrationintheprovisionofphysicalandsocialinfrastructuresuch as public transport, schools, amenities andotherfacilitiescombinetocreateplacespeople want to live in.

Additionalfeaturesofsustainableneighbourhoods include:

• Compactandenergyefficientdevelopment;

• Prioritisingsustainablemodesoftransport;

• Provisionofagoodrangeofamenitiesandserviceswithineasyandsafewalkingdistanceofhomes.

TheimplementationoftheGuidelines for Sustainable Residential Development in Urban Areas (2009) and Smarter Travel (2009) strategysupportanintegratedurbanstructurewherelandusesarespatiallyorganisedaround strategic connections and nodes. Strategicconnectionsaretheprimaryroutesthatconnectplaces.Nodesformwherethese routes converge and intersect. Within Ireland there is a long established pattern ofdevelopmentevolvingatnodes(suchascross roads and river crossings) as these tend to be the most connected places. It is this connectivitythatallowsthecities,townsandvillagestogrowandthrive(seeFigure3.1).

Theintegrationoflanduseandtransportationencouragetheconsolidationofdevelopmentalong strategic connections and around nodes(includingcity,townandvillagecentres). The strategic connections are also themajorroutesforpublictransport,andthenodestheirprimarydestinationorinterchangehub.Thismaximisesaccessibilitytoservicesandpromotestheuseofmoresustainableformsoftransportation,thusreducingcardependency.

Centres form the ‘hub’ of sustainable urban development through the formation of connected compact communities.

Positioning centres away from strategic routes deprives them of life and passing trade.

The answer is to create pedestrian and public transport orientated centres at the convergence of strategic links.

Figure 3.1: The creation of connected centres forms the backbone of integrated land use and transportation development. Base images from the UK Urban Design Compendium (2000) and UK Urban Design Taskforce.


Figure3.2illustratesanabstractmodelofan integrated land use and transportation settlement structure at a metropolitan scale, withanindicativestreethierarchy.Thissettlement pattern has universal application and can be adapted according to the scale ofasettlement.Itmayalsobeadaptedaccordingtoaccessibilitybypublictransport.Forexample,asvehiculartraffic(andinparticularthroughtraffic)convergesoncity,townandvillagecentres,itmaybedivertedaroundthecorearea,allowingmoreefficientservicebypublictransportroutes.

Thisstructureshouldbesupportedbyapermeable and legible street network that offersroutechoiceandflexibilityformanagingmovement within it. These approaches are discussed in the ensuing sections with regard tothedesignandmanagementofstreetnetworks.

Figure 3.2: At a larger scale land use and transport integration occurs where more intensively developed areas are spatially organised around strategic links and centres/nodes.

CITY CENTRE

TOWN CENTRE

VILLAGE CENTRE

NEIGHBOURHOOD

Transit Orientated Centre

Traditional Centre


3.2 Movement and Place

3.2.1 Movement Function

Themovementfunctionofastreetisgenerallydescribedusingaclassificationsystem,suchasastreethierarchy.Thisguidereferstostreethierarchyasfollows(seeFigure3.3):

• Arterial Streets• Link Streets • Local Streets

Table3.1illustrateshowstreet/roadhierarchiescontained within other relevant documents arecross-referencedwiththeabove.

Thenatureofthisstreethierarchyiswellunderstood.Ingeneral,greaterlevelsofconnectivityarerequiredbetweensignificantdestinations,particularlythosegeneratingorattractinglargevolumesoftraffic.

Notes Note1:LargerRegional/DistrictDistributorsmayfallintothecategoryofArterialwheretheyarethemainlinksbetweenmajorcentres(i.e.towns)orhaveanorbitalfunction.

Note2:LocalDistributorsmayfallintothecategoryofLocalstreetwheretheyarerelativelyshortinlengthandsimplylinkaneighbourhoodtothebroaderstreetnetwork.

DMURS Description Roads Act/DN-GEO-03031

Traffic Management Guidelines

National Cycle Manual

Arterial National PrimaryDistributorRoads

Distributor

Link Regional(see note 1)

DistrictDistributorLocal Collector(see Notes 1 and 2)

Local Collector

Local Local Access Access

Table 3.1: Terminology used within this Manual compared with other key publications.

DesignersmustconsidertheFunctionofastreet/street network. In general, as the movementfunctionincreasesthestreet,designers:

• Shouldoptimisethemovementofpublictransport.

• Shouldcaterforgreaternumbersofpedestriansandcyclists.

• Mayneedtocaterforhighervolumesoftraffic.

This approach should have regard to settlement size. For example an Arterial Street throughacitymayhavetocaterformuchlargervolumesoftrafficthanthatinavillage.


LINK STREETS

LOCAL STREETSThese are the streets that provide access within communities and to Arterial and Link streets.

These provide the links to Arterial streets, or between Centres, Neighbourhoods, and/or Suburbs.

HIGHER

LOWER

Figure 3.3: FUNCTION AND THE IMPORTANCE OF MOVEMENT

These are the major routes via which major centres/nodes areconnected.Theymayalso include orbital or cross metropolitan routes within cites and larger towns.

ARTERIAL STREETS


3.2.2 Place Context

Oneofthecriticismsoftheclassificationledapproachisthatthesamesetofstandardsareappliedalongtheentireroute,regardlessofContext. Urban roads and streets can traverse manyareaswithverydifferentcharacteristics,such as industrial areas, residential areas, mixeduseneighbourhoodsandcity,townandvillagecentres(seeFigure3.4).Thisclearlyrequiresdifferentdesignsolutionswithineachofthesedifferentcontexts.

TheIrishurbanlandscapecontainsanarrayofplacesthathavetheirownuniquesetofcharacteristics. Where there are collective similaritiesbetweenthecharacteristicsofplacetheycanbedefinedasaparticularContext.Forthepurposesofthisguide,Contextisclassifiedas:

• Centre;• Neighbourhood;• Suburb; and• BusinessPark/IndustrialEstate;

In general, place status will be elevated where densitiesandlanduseintensityisgreater,resultinginhigheractivitylevels(inparticularpedestrianactivity).

DesignersmustconsidertheContextofastreet/street network. In general, as the place valueofastreetincreases:

Figure 3.4: A street or road may pass through a number of different contexts along its route. As context changes, the design of streets and roads will need to change accordingly.

RURAL FRINGE

INDUSTRIAL ESTATE

TOWN CENTRE

SUBURBVILLAGE CENTRE

NEIGHBOURHOOD

NEIGHBOURHOOD

CITY CENTRESUBURB

TOWN CENTRE

• Greaterlevelsofconnectivitywillberequiredasaccessibilitydemandswillbehigher.

• Higherqualitydesignsolutionsshouldbeimplemented that highlight and promote theimportanceofplace.

• Higherlevelsofpedestrianmovementshouldbecateredforandpromotedtosupport vibrant and sustainable places.

• Higherlevelsofintegrationbetweenuserswillberequiredtocalmtrafficandincreaseeaseofmovementformorevulnerable users.

Figure3.5summarisestherelationshipbetweenplace status and context.

InmostcircumstancesthecharacteristicsofaplaceenabletheclassificationofitsContext tobereadilyidentifiable.Thereareplaceswhere context will be more ambiguous. In such cases designers should undertake aprocessofanalysiswhichidentifiesthecharacteristicsofaplace.1

1 Furtherguidancetoassistdesignersinidentifyingcontext will be published as downloadable content toaccompanythisManual.


CENTRES

Centresincludeareasthatarethefocusofeconomicandculturalactivity.Manycities,townsandvillagesaredefinedbytheimageofstreets within their Centres.Placestatusisatitshighest.LargerCityandTowncentresmayoccupyanumberofblockswhilstsmallerVillagecentresmayonlyoccupyasinglestreet.Pedestrianactivityis high as this is where most people are travelling to and once there, willmostlikelytravelonfoot.PedestrianactivityishighestinCentre streetsthatcontainaconcentrationofretailandcommercialfrontagesthatdirectlyopenontothestreet.

HIGHER

LOWER

Figure 3.5: CONTEXT AND THE PLACE VALUE OF STREETS

NOTE:1. ThisreferstoexistingShopping Centresdevelopedtoservicelowerdensityareas.Thesegenerallydonotdisplaythecharacteristicsassociatedwithhighlyvaluedplacesduetotheirinwardlookingnatureandfocusonvehiclemovement(includingextensiveareasofsurfaceparking).Theirimportanceasdestinations gives them a high place value that needs to be better responded to should these centres undergosignificantredevelopment.

NEIGHBOURHOODS

Neighbourhoodsincludenewandexistingareaswhichareintensivelydevelopedwithmediumtohigherdensityhousingand/orcontainabroadmixofuses.Theseareasgenerallyincludeolderareasthatrepresentthefirststagesofurbanexpansionsandmorerecentlydeveloped compact communities located towards the peripheries ofcitiesandtowns(i.e.thoseinexcessof35dwellingsperha).Pedestrianactivityrangesfromhighertomoremoderatelevels.Thehighestlevelsofpedestrianactivityoccuralongmajorstreetswhichconnect destinations, where public transport services run. Such streetsmayalsocontaindispersedretailandcommercialfrontages.

SUBURBS

Suburbspredominantlyconsistofexistinglowerdensityhousingdevelopedoverexpansiveareas.TheplacestatusofstreetsishardertodefinewithinSuburbs.Manyoftheseareasareattractivelivingplaceswhicharehighlyvaluedbyresidentsfortheirgreenqualitiesandsenseoftranquillity.However,manyareasarecriticisedfortheir‘placelessness’,duetoalackofconnectivityandahighfrequencyofstreetsand‘distributorroads’thataredevoidofdevelopment.Manyofthesecharacteristicscontributetolowerlevelsofpedestrianactivity.

BUSINESS PARKS/INDUSTRIAL ESTATES

BusinessParks/IndustrialEstatesareareasthatareprimarilyfocusedon(andoftenpurposebuiltfor)providingareasofcommercialandindustrialactivityoutsideofCentres. Streets within these areas generallyhavealowplacestatusasbuildingshavelittlestreetpresenceandtheyarelargelydevoidofpedestrianactivity.Manyoftheseareasareinastateoftransitiontowardmoreintensivecommercial and residential uses replacing older industrial ones. As thistransitionoccurs,thestatusoftheseplaceswillrise.PlacestatusinexistingcampusstyleBusiness Parks also tends to be higher and pedestrianscanbehighlyactiveintheseareasduringbusinesshours.


CITYCENTRE TOWNCENTRE VILLAGECENTRE SHOPPINGCENTRE 1

MIXEDUSECORE MEDIUM/HIGHERDENSITYEARLYRESIDENTIAL 2

LOWDENSITYRESIDENTIAL3

BUSINESSPARK3INDUSTRIALESTATE

NOTE:2. Someareasmayhavedensitiesbelow35dwellingsperhectarewheresitesarelongandnarrow.Fromastreetdesignperspectivetheyarecompactneighbourhoodsduetotheirnarrowfrontages(i.e.finegrain)andproximityofdwellingstothestreet/continuityofthebuiltform(i.e.strongsenseofenclosure).

NOTE:3. Theexampleslistedaboveareillustrativeofexistingcontexts.Futuredevelopmentorretrofitschemesinanyofthecontextsindicatedabovemustbesubjecttonationalpolicyonsustainabledevelopmentassetoutinrelevantpolicydocumentsandtotheprinciples,approachesandstandardscontainedwithinthisManual.

Cork Bray,Co.Wicklow Killiney,Co.DublinBlanchardstown,

Co.Dublin

Knocknacarra,Galway

Limerick Donnybrook,Dublin Adamstown,Co.Dublin

CityWest,Co.DublinPouladuff,Cork

birds eye images from www.bing.com/maps/


Transition Areas

There are also those Contexts where designers shouldprovideatransitionfromthoseroadsbuilttoNRADMRB(historic)orDN-GEO-03031RuralRoadLinkDesign(2017)ledstandardstothoseroadsandstreetsdescribedbythisManual.Theseinclude(andasfurtherdetailedinSection3.3.4Wayfinding):

• In Business Parks/Industrial Estates undergoingaperiodoftransitiontowardmoreintensiveformsofcommercialandresidential development, designers should caterforincreasedlevelsofpedestrianactivity(seeFigure3.6).

• In the Rural Fringe when moving between rural areas and cities, towns and villages (seeFigure3.7).

Managing transitions within Business Parks/Industrial Estates presentsaseriesofchallenges to designers. As development withintheseareasintensifies,designersareencouraged to move toward standards that arebettersuitedtodenselypopulatedurbanareas (i.e. Centres and/or Neighbourhoods). However,theimplementationofstandardswhich seek to slow vehicular movement andincreasepedestrianmobility(suchasnarrowercarriagewaysortightercornerradii),maybemoredifficulttoimplementduetothemanoeuvrabilityrequirementsoflargervehicles. Under such circumstances designers mayconsideradditionalmitigationmeasures(asfurtherdetailedinChapters4and5).

ManyRural Fringe areas act as transitional Gateways between the rural and more urban/suburbanformsofdevelopment.TheseareasmaybetreatedasaTransition Zone(seeSection3.3.4Wayfinding).Insuchcircumstances, designers should implement a seriesofmeasuresaimedathighlightingthistransition and slowing drivers. Further advice in this regard is also contained throughout Chapters4and5andwithinAdvice Note 1: Transition Zones and Gateways.

Figure 3.6: Sandyford Industrial Estate, Co. Dublin, is undergoing a process of significant change from an industrial estate to a mixed use area of centre/urban qualities. The new crossing in the foreground in one example of how designers are responding to its rising place value and the needs of pedestrian users.

Source: Google Street View

Figure 3.7: Example of a road that goes through a period of transition between a rural area (top) to that of a town/urbanised area (bottom) (image source: Google Street View).

Source: Google Street View

RURAL

RURAL FRINGE

TOWN


3.3 Permeability and Legibility

3.3.1 Street Layouts

The movement towards more integrated and sustainableformsofdevelopmentwillresultinashiftawayfromdendriticstreetlayoutstohighlyconnectednetworkswhichmaximisepermeability,particularlyforpedestriansandcyclists.Whendesigningnewstreetnetworksdesigners should implement solutions that supportthedevelopmentofsustainablecommunities. In general, such networks should:

• bebasedonlayoutswhereallstreetsleadtootherstreets,limitingtheuseofcul-de-sacs that provide no through access.

• maximisethenumberofwalkable/cycleableroutesbetweendestinations.

Maximising the connections within a site will allow the street network to also evolve over timetomeetlocalaccessibilityneeds.Thiswilllimittheuseofcul-de-sacsthatdonotallowthroughaccessibilityforallusers.Thesestreetsshouldbelimitedtoareaswheremid-blockpenetrationisdesirable(seeSection3.3.2BlockSizes).Figure3.8illustratesthreenetworktypologiesthatcanbeadaptedtotheneedsofplace.

Street networks that are orthogonal (see Figure 3.8a)innaturearethemosteffectiveintermsofpermeability(andlegibility).WithintheIrishcontextorthogonalorgridlayoutsareoftenfoundwithintheCentres and Neighbourhoods developedbetweentheGeorgianandEdwardianperiods(e.g.LimerickCityCentre).MorerecentsuccessfulexamplesincludeDublinDocklandsandBelmayne,Co.Dublin.

Street networks that are curvilinear (see Figure3.8b)mayalsobehighlyeffective.WithintheIrishcontext,thesetypesofgridsareoftenfoundwithinSuburbs developed fromthe1920sonwards(e.g.MarinoandCabra,Dublin).Morerecentlydesignershavesuccessfullyusedsimilargeometricpatternsinhigherdensitydevelopmentstodrawpeopletoward spaces, highlighting Focal Points (seeSection3.3.4Wayfinding)andcreatingattractive curvilinear streetscapes. More recentsuccessfulexamplesincludeClongriffin,Co.Dublin.

Figure 3.8: Permeable street layouts may be formed via a number of different configurations including examples of the more rigid orthogonal, curvilinear and/or organic.

a) ORTHOGONAL LAYOUT BELMAYNE

b) CURVILINEAR LAYOUTCLONGRIFFIN

c) ORGANIC LAYOUTPOUNDBURY


Street networks that are organic (see Figure 3.8c)haveusuallydevelopedovertimeinahaphazardmanner,butcanbehighlyconnected. As noted in the Urban Design Manual (2009)themoreorganiclayoutofsomesmallvillagescanbeverydifferentfromorthogonalgrids,butperformasimilarfunction.ThesetypesoflayoutscanbefoundwithinmanyMedievalorEarlyModernCentres(suchasLusk,Co.Dublin).Organiclayoutsintroduceplacebenefitsbyintroducingvarietyandintrigue.Anexamplewheredesigners have recreated these qualities within arecentlydevelopedareacanbefoundinPoundbury,Dorchester,intheUK.

Thecreationofapermeablenetworkisamulti-layeredprocess.Theprocessshouldbeginwithasiteanalysisthatidentifiesanyconstraintstothedevelopmentofaparticularnetwork(suchasenvironmentallysensitiveareas,topography,existingstructureetc).The process then should move into a design phase. This should outline:

• Pointsofaccess.

• The major destinations (such as Centres and nodes).

• The main strategic connections between destinations.

Thisprocesswillidentifythebasicframeworkfortheapplicationofamoredetailedstreethierarchy.Figure3.9outlineshowthisprocesscanevolveinfoursimplifiedstagesofdesign.This process should also be expanded to take accountof:

• Thelikelynumberoftripsgeneratedbyeachdestination.Thismayresultinadditional Link Streets that are designed to caterforlargervolumesoftraffic(andinparticular buses).

• Movementprioritisationmeasuresforbuses,particularlyalongArterial and Link streets and within Centres (see Section 3.4.3-BusServices).

• Thecreationofacyclenetwork.2

2 Chapter3oftheNational Cycle Manual (2011) outlinesa7stepprocessforNetworkPlanning.

• Possiblerestrictionsonthemovementofprivatevehicles(seeSection3.4.1VehicularPermeability).

DesignersmayrefertoAppendix1oftheUrban Design Manual (2009) which provides severalexamplesofananalysisprocessand the subsequent design outcomes. This includesanumberofextensionstoexistingareas. Understanding the historical context ofaplacewillgiveagreaterappreciationofthewayitevolvedandthestreetpatternsthatexist.Thisisparticularlyimportantforextensionsto existing towns and villages and should help avoidtheimpositionofincongruousstreetlayouts.


Figure 3.9: Illustrations of the creation of a structured and permeable grid network as a multi-layered process.

1. CONNECTION OPPORTUNITIES

Thesiteanalysisshouldidentifytheconnection opportunities (1) within a site including the major destinations (such as Centres and nodes) within it and access fromthesurroundingarea.

2. MAIN STRATEGIC LINKS

Theconnectionoptionsformthebasisforthe main Strategic links (2) into and through thesite.Theserouteswillformtheprinciplecorridorsforthemovementofpedestrians,cyclists,publictransportandvehicleswithin andthroughthesite.Theyshouldbeasdirect and as continuous as is possible withintheconstraintsofanysite.

3. ACCESS AND CIRCULATION

Further links and connections will be neededtoallowforpermeabilitywithinanetwork.Thecreationofroutesfor(3)accessandcirculationensureallpartsofthesiteareaccessiblefromanumberofdifferentdirections.

4. DETAILED DESIGN

As the process moves into (4) detailed design, designers will need to address furtherstructuralissues,includingblocklayouts,mobilitylevelsfordifferentusersandthestreethierarchy.

ARTERIAL LINK LOCAL


3.3.2 Block Sizes

Designersmustalsohaveregardtosizeofblockswithinastreetnetworkandhowtheyimpactonpermeability.Smaller,morecompactblocksshouldbefocusedaroundCentrestooptimiseconnectivity.LargerblocksizesmayoccurawayfromCentres, through lessintensivelydevelopedareas(seeFigure3.10).Withregardtoblockdimensions:3

• Ablockdimensionof60-80misoptimalforpedestrianmovementandwillsustainavarietyofbuildingtypes.Thisrangeofdimensionsshouldbeconsideredforusewithinintensivelydevelopedareas,suchasCentres,tomaximiseaccessibility.

• Larger blocks within Centres and Business Parks/Industrial Estates mayberequiredtocaterforlargercommercialorcivicdevelopments.Insuchcasesmid-blockpedestrian links should be provided.

• Ablockdimensionofupto100mwillenableareasonablelevelofpermeabilityforpedestriansandmayalsobeusedinNeighbourhoods and Suburbs.

Withinadevelopmenttheremaybesectionsofasitewhereaccessibilityrequirementsareloworwherethesiteconstraintsmaynotfacilitateamorepermeableblockpattern.Wherethisoccursdesignersmayneedtoapplylargerblockdimensions.However,alleffortsshouldbemadetoensurethemaximum block dimension does not exceed 120m. On larger and/or irregular blocks shortcul-de-sacsmayalsobeusedformid-block penetration to serve a small number ofdwellingsandtoenablemorecompact/efficientformsofdevelopment(seeFigure3.11).

3 DesignersmayalsorefertoSection3.7.2oftheUK Urban Design Compendium (2000)forfurtherguidanceonblocksizesandpermeability.

Figure 3.10: Optimal block dimensions in varying contexts that will promote a walkable neighbourhood.

60m

80m

OPTIMAL BLOCK SIZE

100m

60m

LARGER BLOCK

Figure 3.11: An example of a short cul-de-sac which is used to penetrate an irregular/larger block and serves a small number of dwellings.

120m

LARGE/IRREGULAR BLOCK

Private Parking Court


3.3.3 Retrofitting

Smarter Travel (2009) recognises that sustainable travel can be supported through retrofittingandrequiresthatlocalauthoritiesprepareplanstoretrofitareasinordertocreate more sustainable neighbourhoods.4 Theretrospectiveapplicationofapermeablenetworktoincreaseconnectivitylevelswithinmore segregated street patterns can be problematic.Thedendriticnatureofsomeofthesestreetpatternsoftenmeansthatconnectionopportunitiesareverylimited.

Well placed links can lead to substantial benefitsforthelocalcommunityintermsofreducingwalkingdistancestoessentialservices.Researchhasfoundthatincreasedlocalmovementisalsobeneficialtosecurityasitcanincreaselevelsofpassivesurveillance.5 Designersshouldseektoengagecloselywithlocalcommunitiestohighlightsuchbenefits.

4 RefertoAction4ofSmarter Travel (2009).5 Referto An Evidence Based Approach to Crime and

Urban Design (2009).

Figure3.12illustratestworecentlyconstructedpedestrianandcyclistconnectionsmadeinDublin.Bothexamplessignificantlyreducedwalking times to public transport (top) and local shops (bottom). The bottom example includedconsultationsessionsandasurveyofresidentspriortotheformalplanningprocess.Thissurveyindicatedthat86%ofthelocalcommunity(locatedwithina10minutewalkingcatchment)supportedthelink.Postconstructionmonitoringhasalsofoundupto500peopleadayusingthelink.6

Therearealsoanumberofprocessesanddesignprinciplesthatmayalsoassistingaininggreatercommunitysupport:

• Focusontheprovisionofpedestrian/cyclistonlylinks.

6 Source:SouthDublinCountyCouncil.

Figure 3.12: An example of two local permeability projects in Dublin which have significantly improved local access to the LUAS (top) and local shops (bottom) for pedestrians and cyclists. These links formalised routes that were used by locals which previously involved walking across unlit fields, muddy patches and/or climbing over/through fences.

BEFORE

BEFORE AFTER

AFTER


• Ratherthanseekingtoretrofitafullypermeable network (i.e. maximising allconnections),focusonkeydesirelines where the maximum gain can be achievedthroughtheminimumamountofintervention.

• Ensureanyplanclearlyhighlightsreductionsinjourneytimes,walkingdistancesetc.(seeFigure3.13).

• Identifypotentialreductionsinprivatevehicleuseorincreasesincyclingandwalking.

• Ensurelinksareshort,overlooked,haveclear sight lines and are well lit to mitigate anti-socialbehaviour.Longerlinksshouldbe limited to those which go through areas ofopenspace.

• Implementapackageoflandscapeimprovementsthatwilldirectlyaddtotheattractivenessofanarea.

Figure 3.13: Connectivity study undertaken for the Tallaght Town Centre LAP identified how a short link intervention through an area of open space (achieved by providing a path, crossing and partial removal of a fence) could significantly increase the number of households within the 400m walking catchment to the LUAS station (base map source:www.bing.com/maps).

LUASCurrent 5 minute walking catchment

Potential 5 minute walking catchment

• Implement parking management plans (suchaspayanddisplay/controlledparkingpermits)tomitigateanypossibleinfluxofvehiclesseekingto‘parkandride’on neighbouring streets.

• Wherepossible,focusonformalisingrouteswhicharecurrentlyusedbymoreablepedestrians but due to barriers are not suitableforusebythemobilityImpairedand disabled.


3.3.4 Wayfinding

Wayfinding,orlegibility,relatestohowpeoplecanfindtheirwayaroundanarea.Forpedestriansandcycliststhisisofparticularimportanceastheyaremorelikelytomovethroughanareaiftherouteisclear.Therearemanytoolsthatdesignerscanusetoprovideaseriesofdesigncuesbywhichpeoplecanorientate themselves. For example, changes inbuildingheightandform,materialsandfinishesandlandscapefeatures.Froma broader perspective designers should ensurethatjourneysthroughthenetworkarerelativelystraightforward.Ingeneral:

• Themoretheorthogonalstreetlayoutthemore legible it will be (as well as being the most connected).

• The network should be structured to draw people towards Focal Points such as Landmarks, Gateways and other civic buildings and spaces.

Figures3.14and3.15illustratehowlegibilitycanbeachievedwithstreetnetworksbydrawingpeopletowardkeydestinationsorFocal Points.

Figure 3.14: Poundbury, Dorchester, UK. The network of interconnecting streets directs people toward a central location, whilst also allowing for route choice (base map source: Google Earth).

Figure 3.15: The Newcastle LAP (South Dublin County Council) illustrates how movement within the village is structured by connecting major Focal Points, which are also used to slow/discourage through traffic.

FocalPoint

Connection


Figure 3.17: Example of a Gateway from Adamstown, Co. Dublin, where changes to the built form and landscaping treatments add to the sense of enclosure and create a formal entry point.

ToIncreaseeffectivenessthestreetsaroundFocal Points require a more individualised design response that highlights their high placevalue.Thesearefurtherdiscussedbelowinrelationtotheirimplicationsforstreetdesign.

Landmarks and civic buildings and spaces

Landmarksarefeaturesthatstandoutfromtheirsurroundsandarevaluedbythebroadercommunityfortheiraestheticand/orhistoricqualities.Examplesincludeatallorhistoricbuilding, archaeological site or landscape feature.Civicbuildingsandspacesgenerallyincludelocalfacilitiessuchasareasofopenspaceandbuildingsofcivicimportance.Areasofopenspaceincludeparks,squaresorplazas.Buildingsofcivicimportanceincludeawiderangeofplacessuchasschools,churches, hospitals and other institutions.

Designersshouldhighlightthese Focal Points by(seeFigure3.16):

• Ensuringthatpedestrianfacilitiesareadequatetocaterforlargenumberofvisitors.

• Trafficiscalmedusingsurfacetreatmentsandotherelementsthatfurtherhighlighttheimportanceoftheplace.

Gateways

Gatewaysareusedtodemarcateapointofarrivalfromoneplacetoanother.Theyareimportantplacemakingtoolsastheyformthe‘firstimpression’ofaplace.Gateways are alsoanimportanttraffic-calmingtoolastheycanbeusedtoinformdriversofachangeindrivingconditionsahead.CommonformsofgatewaysinIrelandoccurattheentrancestoresidential estates and on National Roads at approaches to villages.

Tocreateaneffectivegatewaythataddsvalue to place designers should:

• Useelementsofplacesuchaslandscapeandbuiltformtocreateastrongsenseofenclosure(seeFigure3.17).

• Usematerialchangesandstreetfurnitureassupplementarymeasures(seeFigure3.18).

Figure 3.16: Illustration of surface treatments in Dundalk, Co. Louth. These treatments enhance the sense of place by expanding the square into the adjacent streets and are an effective way of improving pedestrian mobility and calming traffic.


Transition Zones

A Transition Zonereferstoanareathatmaybeneededforslowingvehicleswhenenteringanurbanareafromafastermovingroad,suchasfromaruralroadintoacity,townorvillageorfromamotorwayintoanintegratedstreetnetwork(seeFigure3.19).Designersshouldemphasise Transitions Zonesby:

• Introducing measures that provide enclosure, such as large trees.

• Applyingtransitionalgeometricmeasures,suchasthenarrowingofcarriageways.

• Applyingchangestocarriagewaysurfacingmaterials.

ThelengthofaTransition Zonewilllargelybeinfluencedbytherequiredreductioninspeed.Designersshouldalsotakeintoaccounthowvisible/prominentanysubsequentGateway is. IfaGatewayishighlyvisiblefromadistance,a Transition Zone maynotbenecessaryasdriverswillinstinctivelybeinclinedtoslow.

Figure 3.19: Illustration of a Gateway and Transition Zone that reinforces a large speed reduction when entering an integrated street network.

Figure 3.18: Image from Traffic in Villages (2011) showing a various number of gateway treatments designed to enhance the character of the village and calm traffic.

GATEWAY

TRANSITION ZONE

Integrated Street Network

Motorway


3.4 Management

3.4.1 Vehicle Permeability

Integrated networks do not require the samedegreeofrestrictionstobeplacedonthemovementofvehiclesasisappliedtomore conventional/segregated networks. A networkofintegrated/self-regulatingstreetsprovidestheframeworkforhigherlevelsofaccessibilityforslowmodes(includingmotor vehicles at slow speed) and strategic continuityforcross-networkmodesatmoremoderate speeds (such as public transport) as (seeFigure3.20):

• TheslowernatureofLocal streets (i.e. 10-30km/h)willresultinthembeinglessattractivetothroughtraffic.Althoughtripsthrough Localstreetsmaybemoredirect(andthereforelegible),thetraffic-calmednatureofthesestreetsmaynotnecessarilyresultinsignificantadvantagesinoveralljourneytimes.

• ThroughtrafficwillbeattractedtoArterial/Link streets where trips are more direct and aredesignedtocaterformoremoderatespeeds(i.e.upto50km/h).

• PublictransportalongArterial/Link streets canbeprioritisedbymeasuressuchasQuality Bus Corridors and Bus Lanes (see Section3.4.3BusServices).

Thereareanumberofadvantagestomore permeable networks in regard to the managementoftrafficandvehiclespeedssuch as:

• Driversaremorelikelytomaintainlowerspeeds over shorter distances than over longer ones. As drivers are able to access individualpropertiesmoredirectlyfromAccess/Link streets (where speeds are moremoderate)theyaremorelikelytocomplywithlowerspeedlimitsonLocal streets(seeFigure3.21).

• Permeablelayoutsprovidemorefrequentjunctionswhichhaveatraffic-calmingeffectasdriversslowandshowgreaterlevelsofcaution.7

7 RefertoWhose Street is it Anyway? Redefining Residential Street Design(2006).

Figure 3.20: Examples from Adamstown, Co. Dublin. Through routes (top) are designed to cater for more moderate speeds and to prioritise public transport movement. Local streets (bottom) are slower moving, thus discouraging use by through traffic.

Figure 3.21: Drivers are more likely to comply with posted speed limits where less time is spent on streets with a low design speed (as per the bottom example)

A

B

A

B


• Increasing access to neighbourhood cells can result in the more equitable distribution oftrafficandtheimpactsofcongestionasitisnolongerconcentratedonafewselect junctions or local access streets (see Section3.4.2TrafficCongestion)andnoiseandairpollution(seeSection3.4.5NoiseandAirPollution).

• Thevalueofplacecanalsobeimprovedasslowermovingtraffichaslessimpactonthe surrounding environment (see Section 3.4.5NoiseandAirPollution).

• Frequent entrances to a neighbourhood cellcanreducethesizeofindividualjunctions and streets. This will reduce thepotentialforseverancebetweencommunities and increase pedestrian/cyclistmobilityasstreets/junctionsaremore compact and easier to navigate.

Designersmaybeconcernedthatmorepermeablestreetlayoutswillresultinahigherrateofcollisions.However,researchhasshownthatthereisnosignificantdifferenceinthecollisionriskattributabletomorepermeablestreetlayoutsinurbanareasandthatmorefrequentandlessbusyjunctionsneednotleadtohighernumbersofaccidents.8

Thedegreetowhichpermeabilityisprovidedfordifferenttransportmodescanbecategorisedintofourtypes(seeFigure3.22):

• Dendritic Networkswhichplacesignificantrestrictionsonmovementforallusers.

• Open Networkswhichallowfullpermeabilityforallusers.

• 3 way Off-Set Networks which contain a largeproportionof3wayjunctions.

• Filtered Permeability networks which allowfullpermeabilitytosomeuserswhilstplacing greater restrictions on others.

8 Referto Whose Street is it Anyway? Redefining Residential Street Design(2006)and‘Safenet’analysisManual for Streets: Evidence and research (2007).

Figure 3.22: Types of Street Network identified within Road Safety Planning: New tools for Sustainable Road Safety and Community Development (2007).

DENDRITIC NETWORK

3 WAY OFF-SET NETWORK

FILTERED PERMEABILITY NETWORK

OPEN NETWORK


DesignersshouldavoidthecreationofDendriticnetworkswhichplaceheavyrestrictionsonmovement.Theuseofcul-de-sacsthatdonotallowthroughaccessforusersshouldberestrictedthroughoutanynetwork(seeSection3.3.2BlockSizes).

Open Networksplacefewrestrictionsonthepermeabilityofusers.TheyarebestsuitedtocontextswheremaximumaccessibilityisdesirableforalluserssuchaswithinCentres. Open NetworksmayalsobedesirableinBusiness Parks/Industrial Areas to allow more efficientaccessforcommercialvehicles.

3 Way Off-Set Networks allow through movementforallmodes,however,theydiscouragefastermodesbyrequiringvehiclesto slow, stop and/or change direction repeatedlywhentravellingalongLocal streets. Such networks are suitable to all contexts, but there are limitations to their overall effectiveness.Theuseofmultiplejunctionsoff-setscanreducelegibility.Thiscandiscouragewalking/cyclingasthenetworkisdifficulttonavigate and the route unclear (as well as increasingjourneytimes).Itcanalsoresultindriverfrustration,asnotedabove.

Filtered Permeability Networks, which restrict universalpermeability,maybeappliedwhere designers are seeking to prioritise the movementofmoresustainablemodes(i.e.pedestrians,cyclistsandpublictransport)overprivate vehicles. For example bus gates and othermeasures,mayalsobeusedtoprioritisebusmovements,particularlyinCentres (see Section3.4.3BusServices).Thelimiteduseofvehicularcul-de-sacsmaybeconsideredinNeighbourhoods and Suburbs where there is a particularconcernregardingthroughtraffic.

Theuseofvehicularcul-de-sacstoenforceFiltered Permeability networks should be approached with caution. Their overuse can resultinmanyofthenegativesassociatedwithDendriticnetworksbeingreplicated.Additional design measures should be applied toensurethatpedestrianandcyclelinksarenotperceivedas‘antisocialspaces’.Linksshould maintain clear sight lines and be overlookedbydevelopment(seeFigure3.23).

Figure 3.23: Examples of vehicular cul-de-sacs in Adamstown, Co. Dublin, which allows for through pedestrian and cyclist access only and has incorporated design measures to ensure that it is safe (i.e. clear sightlines and passive surveillance).


Figure 3.24: Example from Drogheda, Co. Louth, of narrow street that was converted from a two-way system to a one way system to facilitate a series of improvements within the town centre that calm traffic, expand the pedestrian domain and strengthen the sense of place.

Withinexistingnetworks,pressureisoftenappliedfromlocalcommunitiestocreatevehicularcul-de-sacs.Designersshouldapproach such requests with caution, as street closureswilloftensimplyshifttheproblemelsewhere.

One-waystreetshavealsobeenwidelyimplemented,retrospectively,inordertofiltervehiclepermeabilityandrelievetrafficcongestion.Theuseofone-waysystemsfortrafficmanagementshouldalsobeapproachedwithcautionbydesignersasthey:

• Promotefasterspeedsasdriversarelikelytodrivefasterwhennoriskisperceivedfromoncomingtraffic.

• Willresultinlongervehicularjourneys,includingthoseforcyclistsandpublictransport.

• Canbeconfusingforuserswhentheydeflectpeopleawayfromdestinations.

• Require additional signage.

Conversiontoone-waysystemsmaybebeneficialonnarrowcarriagewayswherethe street reserve is limited in order to provide additionalspaceforpedestrians,cyclistsandother public realm improvements. Counter flowcyclelanesshouldalsobeconsideredinordertomaintainpermeabilityforcyclistsExamplesincludeCentreswheretheimplementationofaone-waysystemhasdirectplacemakingbenefitsasitallowsforadditionalfootpathwidthand/oron-streetparking(seeFigure3.24).

Thekeytonetworkdesignisbalance.Anoptimal approach to network design is to start fromthepositionofanOpen Network. This willprovideforthedevelopmentofarobustnetwork that can evolve over time to meet thechangingneedsofaplace.PartsofthenetworkmaythenberefinedbyincorporatingelementsofFiltered Permeability Networks and 3 Way-Off Set Networks according to local conditionsandwherethereareclearbenefitsintermsofprioritisingmoresustainablemodesoftransport,improvingsafetyandreducingenergyconsumption.


Figure 3.26: Extract from the Traffic Management Guidelines (2003) showing Traffic flow capacity increasing as speed reduces.

3.4.2 Traffic Congestion

Aprimaryfunctionofalltransportpolicieshasbeentoreducethewasteofresourcescausedbycongestion.Nationalandregional transport policies and plans have recognisedthatitisnotfeasibleorsustainabletoaccommodatecontinueddemandforcaruse. In contrast, sustainable modes (walking, cyclingandpublictransport)cancaterforveryhighvolumesofmovementinafarmoreefficientmanner(seeFigure3.25).Policiesandplans,therefore,promotesustainablemodesoftravelandacknowledgethat,intheabsenceofdemandmanagement,acertainlevelofcarcongestionisinevitable. Oneoftheoutcomesofamoreconnected,traffic-calmednetworkwillbereducedcardependencyandincreaseduseofmoresustainablemodesoftransport.Thisisthemostbalancedwayofaddressingtrafficcongestion.Higherlevelsofconnectivityforall users will also enable greater vehicular permeability,albeitatslowerspeeds.Thebenefitsofthisapproachinclude:

• Slowervehiclespeedsareoftenperceivedtobeacauseofcongestionbutcanleadtoincreasedtrafficcapacity(seeFigure3.26).

Figure 3.25: Illustration of the amount of space required to transport the same number of people via different modes of transport (image source: Munster Planning Office, Germany)

SPACE REQUIRED TO TRANSPORT 60 PEOPLE WITHIN A STREET

• Morefrequentminorjunctionswithfewervehiclemovementscalmtrafficandareeasierforpedestriansandcycliststonavigate.

Withinurbannetworks,delayandcongestionoverwhelminglyoccuratjunctions.Segregatednetworkschanneltraffictowardsfewerjunctionsandthiscanlocallyconcentratethenegativeimpactsoftraffic,resulting in large junctions where bottlenecks occur(seeFigure3.27).Thedesignofjunctionshastraditionallyprioritisedtheminimisationofvehicularqueuinganddelay.Asaresultpedestrianscanfacesignificantdelays.Thisisalsoevidentinthevariouscomputerprogramsusedtoanalysejunctiondesign, which have the calculation and minimisationofvehicularqueuinganddelayastheirprimaryoutputs.Designerswilloftenseek to provide junctions that operate below 90%capacityasmeasuredbytheratioofflowtocapacity(RFC).

CAR BUS BICYCLE


Smarter Travel (2009)requiresgreaterprioritytobegiventothemovementofpedestriansinordertofacilitatemoresustainabletravelpatterns.Thisincludesthereprioritisationoftrafficsignaltimings(bothnewandexisting)tofavourpedestriansandcyclistinsteadofvehicles and to reduce pedestrian crossing distances9(seeSection4.3.2PedestrianCrossingsand4.4.3JunctionDesign).

Thecreationofmorecompactjunctionsthatminimisepedestrianandcyclistwaitingtimes,will place additional pressures on junction performance.Inareaswherepedestrianactivityishigh(suchasinNeighbourhoods and Centres)junctionsmayhavetooperateatsaturationlevelsforshortperiods(i.e.above93%duringpeakperiods).Wherejunctions operate at or near saturation levels andtheyarefrequentedbybusservices,prioritymeasuresshouldensureservicesarenotundulydelayed(seeSection3.4.3BusServices).Wherelongerperiodsofsaturationoccur,pedestriancycletimesmaybeextended.Thisshouldbedoneinpreferencetotheimplementationofstaged/staggeredcrossings(seeSection4.3.2PedestrianCrossings).

9 Refer to Action 16 of Smarter Travel (2009).

Figure 3.27: Highly segregated ‘cell and distributor’ networks channel faster moving traffic to large junctions where bottlenecks may occur (left). More permeable networks result in more frequent minor junctions with fewer vehicle movements (right) which calm traffic and are easier for pedestrians and cyclists to navigate.


3.4.3 Bus Services

Streetnetworksunderpintheefficiencyandsustainabilityofpublic-transportand,consequently,theabilitytofacilitatehigherdevelopment densities along public transport corridors in accordance with the objectives ofSmarter Travel (2009). This includes an objective that all houses within urban areas arelocatedwithin800mofabusroute/stop.10Permeablenetworkswhichmaximiseconnectivitywillassistinachievingthisobjective. Smarter Travel (2009) also requires theimplementationofbusprioritymeasures,11 such as Quality Bus Corridors and Bus Lanes. These ensure that buses can move through congestednetworkswithminimaldelays.

Designersmusthaveregardtothelocationofbusservicesasastrategicnetworkissue.Ingeneral:

• Busservicesshouldprimarilybedirectedalong Arterial and Link streets as these will be the most direct routes with between destinationswiththegreatestnumberofconnections.

• QBCs or Green Routes should be provided onstreetswhichcaterforhigherfrequencyservices12 over longer distances (see Figure 3.28).

10 ReferalsotoAction13ofSmarter Travel (2009).11 RefertoAction12ofSmarter Travel (2009).12 RefertoBus Connects (NTA)forfurtherinformationon

servicefrequency.

• Onlowerfrequencyroutes,orinlesscongested networks, bus lanes that allowbusestomovetowardsthefrontofqueuingtrafficatjunctionsmaysuffice.Thisapproachmayalsobepreferredonexisting streets where the street reserve is constrained.

Designersshouldconsultwithbusoperatorsregardingtheneedfordedicatedlanes.Under-usedorunnecessarylanes can serve onlytoincreasethewidthofcarriageways(encouraging greater vehicle speeds) and consume space that could otherwise be dedicatedtoplacemaking/traffic-calmingmeasures such as planted verges, wider footpaths,cycletracksorlanesandon-streetparking.

Designersshouldalsoconsidertheuseofbusgates(seeFigure3.29)andselectivebusdetectiontechnologythatprioritisebusestoimprovejourneytimesbyrestrictingother motorised vehicles. These should bestrategicallyplacedthroughoutanetwork, and in particular within Centres, tofilterpermeabilityandensuremorerapidmovementforbuses.

Figure 3.28: QBCs and Bus lanes should be considered on all Strategic Routes where the high frequency services occur or where their future need has been established.

Figure 3.29: Example of a ‘bus gate’ in Tallaght, Co. Dublin, which filters permeability to allow for the free passage of buses whilst excluding other vehicles.


3.4.4 Relief Roads

ThefocusofthisManualisthecreationofplace-based/sustainablestreetnetworks,which balance pedestrian and vehicle movement. However, it is recognised that there are some roads which are required to caterfortheefficientmovementoflargervolumesofmotorisedtrafficatfasterspeedsoverlongerdistances.ThesearegenerallyreferredasInner Relief Roads and Urban Relief Roads.13

Inner Relief Roads aregenerallyusedtodiverttrafficwithinanurbanarea,awayfromaCentre or Node.Thedesignoftheseroutesneedscarefulconsideration.Chapter 2 highlights the issues associated withtheprovisionofhigherspeed/highlysegregated routes though cities, towns and villages.Authoritiesinmanyurbanareashaveattemptedtoovercomeissuesofseverancebyverticallyseparatingtheseroutesintoaseriesoftunnels,cuttingsorelevatedcarriageways.Suchsolutions,however,tendtobereservedformajornationalprojectsandcanhavesignificantnegativeimpactsonplace(seeFigure3.30).

Itismorelikelythat Inner Relief Roads through urban areas will need to occur at moderate speeds(50km/h).Therouteshouldbeintegratedwithintheurbanfabricsothatasenseofplaceismaintainedandtopreventseverance between adjoining areas. There aremanyexamplesinIrelandofstreetsthatcarrysignificantvolumesofthroughtrafficatmoderate speeds and retain a high place value/levelsofconnectivity(seeFigure3.31).Successfulsolutionstendtobedesignedas boulevards with well planted medians andvergesthatprovideabufferbetweentheheavily-traffickedcarriagewayandthe surrounding pedestrian environment. Boulevardsmayalsobedesignedasa‘multiway’boulevardwithacentralcarriagewayforthroughtrafficandaccesscarriagewaysattheside(seeSection3.4.5NoiseandAirPollution).

13 SeeDN-GEO-03031RuralRoadLinkDesign(2017).

Figure 3.31: Dorset Street, Dublin, an example of a street that carries large volumes of traffic and where recent improvements have ensured it maintains an important place function.

Figure 3.30: Examples of major urban roads that move large volumes of traffic via vertical segregation. These require significant investment in infrastructure. As illustrated in the middle and bottom examples they can have negative impacts in terms of place and/or connectivity (image sources: Google Street View).

Gran Via Les Corts Catalanes, Barcelona

Dublin Port Tunnel

M4 London


Urban Relief RoadsaregenerallyroutedaroundurbanareasandarecommonlyreferredtoasBy-Passes or Outer Ring Roads. Designersmayusetheseroutestodirectlongerdistancetraffic,andinparticularHeavyGoodsVehicles(HGVs),awayfromcities,townsandvillagesprovidedtheyareclearlyseparatedfromtheurbanfabric(seeFigure3.32).Urbandevelopmentshouldnotextendtotheedgeoftheserouteswithoutfullintegrationintothesurroundingstreetnetwork. This is a strategic issue that should beresolvedviaaCountyDevelopmentPlan/LocalAreaPlan(seeFigure3.33)andmayalso require close consultation with TII, where theroadispartofthenationalroadnetwork.14 Inthecaseofamotorwayornationalgradeseparateddualcarriagewaythefutureintegrationoftheroadwouldnotbeanoption.

14 RefertoSpatial Planning and National Roads: Guidelines for Planning Authorities (2012).

Figure 3.32 Outer Relief Roads can be used to direct long distance traffic away from cities, towns and villages

Figure 3.33: As urban expands toward an Urban Relief Road (top) a strategic decision will need to be made as to either maintain segregation and ‘leapfrog’ leaving a green belt (middle), or moderate speed, retrofit and integrate route (bottom).

A

B


Speed Reduction dB (A) Reduction

from70-60km/h 1.8

from60-50km/h 2.1

from50-40km/h 1.4

Traffic Volume Reduction

dB (A) Reduction

30% 1.6

40% 2.2

50% 3.0

75% 6.0

Table 3.2: Noise reduction effects of lowering traffic speeds and volumes

3.4.5 Noise and Air Pollution

TheprimarysourceofwidespreadenvironmentalnoiseinIrelandisroadtraffic.Trafficisalsothemainsourceofairpollutantsin cities, towns and villages. Whilst air pollutants generallyhavedeclinedinrecentyears,thosepollutantsassociatedwithtraffichavenot,principallybecauseofanincreaseintrafficvolumes and congestion.15Busyorcongestedroadscancreatepollution‘hot-spots’andcanhaveasignificantnegativeimpactonadjacentstreetactivities.Pollutioncanalsoseriouslyaffecttheattractivenessofwalkingandcyclingalongaffectedroutes.

Themainfactorswhichdeterminethelevelofroadnoiseandairpollutionaretrafficvolume,speed,levelsofcongestionandtheproportionofHGVs.Manyoftheseissuesmaybesubstantiallyaddressedbydirectinglargevolumesoftraffic(andinparticularHGVs)awayfromcities,townsandvillagesvia Urban Relief Routes(seeSection3.4.4ReliefRoads)andbyreducingspeeds(seeTable3.2).Thecreationofapermeablestreetnetworkwhichpromoteswalking,cyclingandpublic transport will also lead to reductions invehiculartrafficandlessconcentrationoftrafficandconsequentlyofnoiseandairpollution.

15 RefertoAir Quality In Ireland (2009).

SPEED AND NOISE REDUCTION TRAFFIC AND NOISE REDUCTION

Itisinevitablethatsomeheavily-traffickedroutes (such as Arterial streets) will pass throughurbanareas.Whilsttrafficvolumeandnoisehaveasignificantimpactonthevalueofplace,therearemanyexamplesinIrelandofstreetsthatcarrysignificantvolumesofthroughtrafficatmoderatespeeds which retain a high place value (as perFigure3.31-DorsetStreet).Whilstsomemitigation measures can be provided through constructionmaterialsusedoncarriagewaysurfacesandwithinadjoiningbuildings,mostintegratedorplace-basedsolutionsshouldinvolve(seeFigure3.34):

• Applyboulevardtypologieswithwellplanted medians and verges that reduce pollution16andprovideabufferbetweentheheavily-traffickedcarriagewayandthesurrounding pedestrian environment.

• Considertheuseofmultiplecarriagewaysthatseparatethroughtrafficfromaccesstrafficandparking.

16 Referalsoto Effectiveness of Green Infrastructure for Improvement of Air Quality in Urban Street Canyons (2012).


Figure 3.34: Examples of Urban Boulevard street typologies which mitigate the impacts of noise through place based design solutions.

ThroughCarriageway Access carriageway

Access carriageway

MainCarriageway

Median MedianMedianParking/Verge

Parking/Verge

MedianParking/Verge

At a broader level, land uses should be distributed in a manner that takes into accountsensitivitytotrafficnoise:

• Commercial or retail uses should be used to shield more sensitive receptors (i.e. residential uses). Such an approach complementstheprincipleofintegratedstreetdesignasitfocusescommercial/retail uses on Arterial and Link streets where publictransportservicesarelikelytobelocated.

• Where residential uses are provided on theupperfloorsofbuildings,aspectsoftheupperfloorsmaybeorientatedsothattheyareperpendicular(i.e.atrightangles)totheroadway.Thiswillensureadegreeofoverlooking,whilstdeflectingtheimpactsofpollution(seeFigure3.35).

Figure 3.35: Example of a development adjacent to a busy Arterial Street where residential development is provided over a commercial podium at street level.

Parking/Verge

CHAPTER 4 - STREET DESIGN

A more integrated approach to street design can create a ‘win-win’ scenario, where designers can enhance the value of place whilst calming traffic and improving pedestrian and cyclist comfort. To achieve this outcome, designers need to consider the multi-functional role of the street and apply a package of ‘self-regulating’ design measures.


4.0 Street Design

4.1 Movement, Place and Speed

4.1.1 A Balanced Approach to Speed

Balancing the priorities Context and Function createsashiftingdynamicinstreetdesign.The UK Manual for Streets (2007) illustrates this relationship as a simple graph depicting some wellknownscenarios(seeFigure4.1).Keytothesuccessfulimplementationofresponsivedesignsolutionsistheissueofspeed,particularlysowithregardtopedestrianandcyclistsafety,comfortandconvenience(seeFigure4.2).Expectationsofappropriatespeedwillvarygreatlyfrompersontopersonandthere is little relevant research on this subject. Intuitivelyonewouldexpectmotorists’toleranceoflow-speedjourneystoincreaseinintensivelydevelopedareas(i.e.fromtheCentres, to Neighbourhoods to Suburbs) and accordingtojourneytype(i.e.fromLocal to Link and to Arterial Streets.

Designermustbalancespeedmanagement,thevaluesofplaceandreasonableexpectationsofappropriatespeedaccordingto Context and Function.1 In this regard:

• Within cites, towns and villages in Ireland a defaultspeedlimitof50km/hisapplied.

• Speedlimitsinexcessof50km/hshouldnotbe applied on streets where pedestrians are active due to their impact on place andpedestriansafety.

• Lowerspeedlimitsof30km/harearequirementofSmarter Travel (2009) within the central urban areas, where appropriate.2

• Wherepedestriansandcyclistsarepresentin larger numbers, such as in Centres, lower speedlimitsshouldbeapplied(30-40km/h).

• Where vehicle movement priorities are low, such as on Local streets, lower speed limitsshouldbeapplied(30km/h).

1 Further guidance in regard to special speed limits isavailablefromSection9oftheRoad Traffic Act - Guidelines for the Application of Special Speed Limits (2011).

2 RefertoAction16of Smarter Travel (2009).

Figure 4.2: Illustration from the Road Safety Authority showing the impact of vehicle speeds on pedestrian fatalities. This is of primary consideration when considering appropriate speeds and levels of pedestrian activity.

Figure 4.1: Illustration from the Manual for Streets 2 (2010) depicting the relationship between place and movement in regard to some well know scenarios.


• LocalAuthoritiesmayintroduceadvisoryspeedlimitsof10-20km/whereitisproposed that vehicles, pedestrians and cyclistssharethemaincarriageway.

Designspeedisthemaximumspeedatwhichitisenvisaged/intendedthatthemajorityofvehicles will travel under normal conditions. In this regard:

• In most cases the posted or intended speed limit should be aligned with the design speed.

• In some circumstances, such as where advisoryspeedslimitsareposted,thedesignspeedmaybelowerthanthelegalspeed limit.

• Thedesignspeedofaroadorstreetmustnotbe‘updesigned’sothatitishigherthan the posted speed limit.

Table 4.1 illustrates the broader application ofdesignspeedsaccordingtoContext and Function.Designersshouldrefertothistablewhen setting speed limits and designing urban streets and urban roads to align speed limits and design speeds.

Table 4.1: Design speed selection matrix indicating the links between place, movement and speed that need to be taken into account in order to achieve effective and balanced design solutions.

ARTERIAL 30-40KM/H 40-50KM/H 40-50KM/H 50-60KM/H 60-80KM/H

LINK 30KM/H 30-50KM/H 30-50KM/H 50-60KM/H 60-80KM/H

LOCAL 10-30KM/H 10-30KM/H 10-30KM/H 30-50KM/H 60KM/H

CENTRE N’HOOD SUBURBAN BUSINESS/ INDUSTRIAL

RURAL FRINGE

CONTEXT

PEDESTRIAN PRIORITY VEHICLE PRIORITY

FUN

CTIO

NWhenapplyingtheselimitsdesignersmustalsoconsiderhoweffectivelytheycanbeimplemented,astheintroductionofmoremoderateand/orlowerspeedlimitsoutofcontext and/or without associated speed reductionmeasuresmaynotsucceed.


Figures 4.3: Illustration of the links between place, movement and speed that need to be taken into account in order to achieve effective self-regulating street environments.

CONTEXT

FUNCTION SPEED

DESIGN RESPONSE

ARTERIAL 30-40KM/H 40-50KM/H 40-50KM/H 50-60KM/H 60-80KM/H

LINK 30KM/H 30-50KM/H 30-50KM/H 50-60KM/H 60-80KM/H

LOCAL 10-30KM/H 10-30KM/H 10-30KM/H 30-50KM/H 60KM/H

CENTRE NEIGHBOUR-HOOD

SUBURBAN BUSINESS/ INDUSTRIAL

RURAL FRINGE

PEDESTRIAN PRIORITY VEHICLE PRIORITY

4.1.2 Self-Regulating Streets

An appropriate design response can successfullybalancethefunctionalneedsofdifferentusers,enhancethesenseofplaceand manage speed in a manner that does notrelyonextensiveregulatorycontrolsandphysicallyintrusivemeasuresforenforcement.In short, place can be used to manage movement.Suchenvironmentsarereferredtoasbeingself-regulating.Withinthisself-regulating street environment the design responseiscloselyalignedwiththedesignspeed(seeFigure4.3).

Within Ireland, the Dublin Traffic Initiative: Environmental Traffic Planning (1995)was,perhaps,thefirststrategicdocumentinIreland to recognise the link between the street environment and driver behaviour. Itcitedtheuseofnarrowstreetsandon-streetparkingastraffic-calmingtools.TheAdamstown Street Design Guide (2010) draws upon research undertaken in regard to the UK Manual for Streets (2007) to advance this approach.Itcitedacombinationofplace-basedpsychologicalmeasuresandintegratedthemwithmoretraditionalphysicalmeasuresinordertocreateaself-regulatingstreetenvironment (see Figure 4.4).3

3 ReferalsotoSection2.2‘SafeStreets’oftheAdamstown Street Design Guide (2010).

Thereisnosetformulaofhowapackageofpsychologicalandphysicalmeasuresshouldbe applied. The design team must take into account that:

• Physicalandpsychologicalmeasuresaremosteffectivewhenusedincombination.4

• Themorefrequentlyandintenselyphysicalandpsychologicalmeasuresareapplied,the lower the operating speed.

AnalysisoftheRoadSafetyAuthorityFree Speed Survey2008,2009and2011,inclusive showed that where there are fewpsychologicalandphysicalmeasures,averagedriversregularlyexceededthepostedspeedlimit.Converselywherethesemeasuresaremorefrequentlyand/ormoreintenselyapplied,driverspeedswerelowerand compliance with the posted speed limit wasgreater(seeFigure4.5).

4 RefertoPsychological Traffic Calming (2005).


Figure 4.4: Extract from the Adamstown Street Design Guide. Illustration of the psychological and physical, or ‘hard’ and ‘soft’, measures that influence driver speeds and may be used to enhance place and manage movement.

Close Proximity of Buildings (left)

Continuous Street Wall (right)

Active Ground Floor Uses (left)

Pedestrian Activity (right)

Frequent Crossing Points and Junctions (left)

Horizontal and Vertical Deflections (right)

Narrow Carriageways (left)

Minimising signage and road markings (right)

Reduced Visibility Splays (left)

On-Street Parking (right)

Tighter Corner Radii (left)

Shared Surfaces (right)


Figure 4.5: Road Safety Authority Free Speed Survey and Street Characteristics

The Road Safety Authority periodically undertakes free speed surveys throughout urban and rural Ireland. In 2008, 2009 and 2011 the speeds of some 9,500 vehicles along 23 streets within metropolitan Dublin were recorded.

An analysis of the characteristics of the street environment at each of the 23 locations was carried out for the preparation of this Manual. This survey recorded the frequency and intensity of psychological and physical design measures that influence driver behaviour, such as those illustrated in Figure 4.4.

The survey results demonstrated that the individual effectiveness of these measures varied. For example, as would be generally expected, the presence of deflections (such as ramps) had a strong influence on reducing speed. Results also showed that other ‘softer’ measures, such as a sense of enclosure, surveillance and activity created by a continuous line of development fronting directly onto the street, have a strong influence on lowering speed.

Overall, the results demonstrated a strong trend whereby as the frequency and strength of the psychological and physical design measures increased, the lower the operating speed and the greater the level of compliance with the posted speed limit (see graphs A and B ). This trend was generally consistent for all road types including those which did not have ramps.

Figure 4.2 illustrates that an increase in vehicle speeds from 50 km/h to 60 km/h nearly doubles the chance of a pedestrian fatality, should they be struck by a vehicle. Graph C is particularly significant in this regard as it illustrates that where there are limited psychological and physical design measures on streets with a speed limit of 50 km/h most drivers will exceed the speed limit by 10 km/h or more. Conversely where the frequency and strength of these measures are high full, or near full, compliance with the speed limit occurred. In many cases the average operating speed dropped below 40 km/h.

LOWER MODERATE HIGHER

70 Km/h

30 Km/h

50 Km/h

Frequency and Intensity ofPsychological Conditions and Physical Constraints

A. AVERAGE OPERATING SPEED


100%

60%


B. % OF DRIVERS EXCEEDING SPEED LIMIT

80%

40%

20%

C. % OF DRIVERS EXCEEDING SPEED LIMIT BY 10 KM/H OR MORE

(50 km/h streets only)


100%

60%


80%

40%

20%


Inretrofitscenarios,designersmustcarefullyconsiderthecharacteristicsoftheexistingstreetenvironmentpriortoimplementingself-regulating measures as:

• The measures contained within this Manual should not be implemented in isolation as theymaynotfullyaddressissuesrelatedtoinappropriate driver behaviour on existing streets.

• Designersshouldcarryoutadetailedanalysistoestablishthelevelsofintervention and design measures required inanygivenscenario(seeFigure4.6).

Figure 4.6: Examples from Youghal, Co. Cork (left), and Dorset Street, Dublin City (right), of retrofitted design responses that are appropriate according to Context and Function. The narrow, enclosed and lightly trafficked nature of the street within Youghal is highly suited to a shared carriageway. The heavily trafficked nature of Dorset Street makes it highly suited to a Boulevard type configuration.

AFTER

BEFORE

AFTER

BEFORE

Forexample,inmanyolderCentres and Neighbourhoods, measures such as connectivity,enclosure,activestreetedgesandpedestrianactivityaregenerallystrong.In these circumstances the design measures containedwithinthisManualmaybereadilyapplicable.Theapplicationofaholisticsolutionmaybemorechallengingwithinamoreconventionalorhighlysegregatedroadenvironments. Under such circumstances a widerpackageofmeasuresmayneedtobeimplemented.

ThisManualcannotaccountforeveryscenario that a designer will encounter. In addition to those examples contained in the ensuing sections, to assist designers in the processofretrofittingitisintendedthataseriesof‘bestpractice’casestudieswillbemadeavailable as downloadable content.


Figure 4.7: Measurements that indicate the sense of enclosure by way of building height to street width ratio and the percentage of the street wall that is solid.

BUILDING HEIGHT TO STREET WIDTH RATIO

CONTINUITY OF THE STREET WALL

1

1

Ratioof1:1-Verystrongsenseofenclosure (street trees optional)

2Ratioof1:2-Strongsenseofenclosure(supplementarystreettreesdesirable)

1

75%+solid-strongsenseofenclosure(street trees optional)

75%solid-moderatesenseofenclosure(supplementarystreettreesrequired)

3Ratioof1:3-Moderatesenseofenclosure

(supplementarystreettreesrequired)

1

4.2 Streetscape

4.2.1 Building Height and Street Width

Senseofenclosureisgenerallymeasuredasaratiowheretheheightofabuilding(measuredfromfrontbuildinglinetofrontbuildingline)ismeasuredagainstthewidthofastreet.Consideration needs to be given as to how consistentlythisratioappliesalongthelengthofthestreetthroughthecreationofastreetwall.Thestreetwallreferstohowcontinuousthesenseofenclosureisalongthestreet.

Enclosingstreetswithbuildingshelpstodefinethem as urban places, creates a greater sense ofintimacy5 and promotes them as pedestrian friendlyspacesthatareoverlooked.Thissenseofintimacyhasbeenfoundtohaveatraffic-calmingeffectasdriversbecomemoreawareoftheirsurroundings.

Designersshouldseektopromote/maintainasenseofenclosureonallstreetswithincities,towns and villages (see Figure 4.7). In this regard.

• Astrongsenseofenclosureshouldbepromoted in large Centres. The most effectivewayofachievingthisiswitha building height to street width ratio greater than 1:2 and street wall that ispredominantlysolid(allowingforintermittentgapsonly).

• Agoodsenseofenclosurecanalsobeachieved with a building height to street widthratioof1:3andastreetwallthatis75%solid,providedacontinuouslineofstreet trees are planted along the street. Thisapproachmaybemoredesirablein smaller Centres or Neighbourhoods where maintaining a more human scale is desirable.

• Astrongsenseofenclosuremaybedifficulttoachievewherethetotalstreetwidthexceeds30mwide,suchasonBoulevards. In such circumstances design teamsshouldemphasisethesenseofenclosurewiththeplantingofcontinuousrowsoflargecloselyplantedstreettrees.

5 RefertoSection07ofthe Urban Design Manual (2010).


• Within established areas creating a strongsenseofenclosuremayresultinbuildingheightsthatwouldconflictwiththoseofthesurroundingarea.Insuchcircumstancesdesignersmayemphasiseenclosure though other design measures, suchastheplantingofstreettrees.

• Theplantingofstreettreesshouldalsobeconsideredasaretrospectivetrafficcalming measure in existing contexts wherelevelsofenclosurearetraditionallyweaker, such as in Suburban areas.

• Theplantingofstreettreesmayalsobedesirable within Transition Zones (see Sections3.4.1Wayfindingand3.4.4ReliefRoads),inadvanceofGateways and within Rural Fringe areas as an advance warningtodriversofchangingconditionsahead.

The measures illustrated in Figure 4.7 should not bestrictlyviewedasquantifiable.Forexamplea moderate building height to street width ratio,inadditiontoamoderatecontinuityofstreet wall, does not equate to a strong sense ofenclosure.Rathertheyshouldbeviewedascomplementary,i.e.astrongsenseofenclosure is created where both elements are strong.

The relationship between building height andstreetwidthisalsokeytocreatingastrongurbanstructure,byincreasingbuildingheights in proportion to street widths. This will alsopromotegreaterlevelsofsustainabilityandlegibilitybyplacingmoreintensivedevelopment along wider/busier streets, such as Arterial and Links streets, to support public transport routes and highlight their importance asconnectingroutes,respectively(seeFigure4.8).

Additionalbuildingheightmayalsobeusedatjunctionstocreatea‘bookend’effect(seeFigure 4.9). This approach will assist in slowing vehiclesastheyapproachjunctionsandwillimprovelegibilitybyhighlightingconnectingroutes throughout the network.

Figure 4.8: Plan illustrating how taller buildings (purple) are placed along busier routes (and around major spaces) to enclose streets and reinforce the structure of the area.

Figure 4.9: Reinforcing junctions with additional building height will assist in slowing vehicles as they approach junctions and will improve legibility by highlighting connecting routes throughout the network.


4.2.2 Street Trees

Streettreesareanintegralpartofstreetdesignastheycontributetothesenseofenclosure,actasabuffertotrafficnoise/pollutionandenhanceplace.Atraffic-calmingeffectcanalsobeachieved,wheretrees are planted in continuous rows and their canopies overhang, at least in part, the vehicularcarriageway.Streettreescanalsobeusedtoenhancelegibilitybyhighlightingtheimportanceofconnectingroutesanddistinguishingoneareafromanotherthroughvariations in size and species selection.

Theplantingoftreesshouldbeconsideredasanintegralpartofstreetdesign.Ingeneral,thesizeofthespeciesselectedshouldbeproportionatetothewidthofthestreetreserve. For example (see Figure 4.10):

• Largerspecies,withacanopyspreadgreaterthan6mwillbebestsuitedtowiderstreets, such as Arterial and Link streets.

• Smallerspecieswithacanopyspreadof2-6mwillbebestsuitedtonarrowerstreetssuch as Local streets.

Designersmayseektovarythisapproachinkeepingwiththecharacteristicsofaplace.For example:

• Sparseplantingmaybemoreappropriatein a Centre, enhancing its urban qualities.

• Smallerspeciesmaybemoreappropriatewhere buildings are located in close proximitytothestreetedgecarriageway(i.e.totakeaccountofovershadowing,growth restrictions).

• LargerspeciesmaybedesirablewithinSuburbs, to enhance the greener character associated with these places.

To be effective, trees should be planted atintervals of 14-20m. This may be extendedperiodicallytofacilitatetheinstallationofotherstreet facilities, such as lighting. Designersshouldalsoconsidertheimpactofrootgrowth.Tree roots may need to be contained withinindividual tree pits, continuous soil planting strips or using other methods to restrict growth under pavements/toward services.

TREE SIZE AND STREET RESERVE

SmallStreetReserve-SmallerSpecies

13-15m

2-3m

2-3m

17-21m

2-3m

4-6m

ModerateStreetReserve-SmallerSpecies

19-23m

4-6m

3-5m

22-25m

4-6m

3-5m

30m+

6-10m

4-6m

26-30m

6-10m

4-6m

LargeStreetReserve-LargerSpecies

Figure 4.10: General guide to the canopy width and clearance height for street trees.


4.2.3 Active Street Edges

Active street edges provide passive surveillanceofthestreetenvironmentandpromotepedestrianactivity.Thisshouldbeaprincipleaimofthedesignteam.Increasedpedestrianactivityalsohasatraffic-calmingeffectasitcausespeopletodrivemorecautiously.6

Designersshouldseektopromoteactivestreetedges on all streets within cities, towns and villages.Themosteffectivewaytopromotepedestrianactivityistoplacebuildingsincloseproximityofthestreet(seeSection4.2.1Building Height and Street Width) with a high frequencyofentrancesandotheropenings.In this regard (see Figure 4.11):

• TomaximiseactivityinCentres the street edge should be lined with development thatpromotesahighlevelofactivityandanimation such as retail, commercial or other appropriate uses. To maximise theeffectivenessoftheseuses,setbacksshouldbeminimised(forexample0-3m)andahighfrequencyofentrancesprovided(forexampleevery5-10metres).

• Wherelargerretail/commercialfloorplatesareproposedatgroundfloorlevelanactivestreetedgemaybeachievedbycreatingmultipleentrancesand/orwrapping them with smaller perimeter units thatfrontontothestreet(seeFigure4.12).

• Arterial and Linkstreetsthroughintensivelydeveloped Neighbourhoodsmayalsosustainretail/commercialactivity,particularlyoncornerlocations.

• Higherlevelsofprivacyaredesirablewhereresidentialdwellingsinterfacewithstreets.Thismaybeprovidedviaasmallsetback(forexample1-3metres)whichincorporatesplantedstripthatdefinespublicandprivatespace(seeFigure4.13).

• Residential development will also promote on-streetactivitywhereindividualdwellings(includinggroundfloorapartments)are‘owndoor’accessed(seeFigure 4.14).

6 RefertoSection2.2.5oftheUK Manual for Streets (2007).

Figure 4.11: Measures that indicate active and animated street interfaces.

FRONTAGE TYPE AND FREQUENCY OF ACCESS

0-3msetbackstrong street presence

SETBACK TO THE PEDESTRIAN FOOTWAY

4-6msetback more moderate street presence

Higherfrequencyretail/commercial-highlevelofactivityandanimation

5-10m

Moderatefrequencyretail/commercial-moremoderatelevelofactivityandanimation

11-16m

Owndoorresidential-moremoderatelevelofactivityandanimation

5-8m


Figure 4.12: Illustration of how a larger retail/commercial unit can be accommodated within a block whilst promoting an active street edge that is also overlooked from the upper levels.

Larger Floorplate

Smaller units‘wrapped’

around perimeter

Development‘Cap’

Figure 4.13: Privacy strip to the front of residential development. The strip provides a buffer and clearly define the private domain from the public.

Figure 4.14: A fine grain residential environment where all ground floor dwellings are directly accessible from the street via ‘own door’ entrances. Note, in this instance access to upper floors is provided via internal lobby areas.

• Greaterflexibilityinregardtosetbacksmaybeneededinexistingareaswheretheyaredefinedbyanexistingpatternofbuilding lines

• Theinclusionofin-curtilageparkingwithinfrontgardens(i.e.tothefrontofthebuildingline)mayresultinlargebuildingsetbacksthatsubstantiallyreducethesenseofenclosure.Inadditiontotheabove, designers should avoid a scenario whereparkingdominatestheinterfacebetweenthebuildingandthefootway(seeSection4.4.9On-StreetParkingandLoading).

Inadditiontotheabove,furtheradvicewithregardtothecreationofactivestreetedgesmayalsobetakenfromtheUrban Design Compendium.7

7 RefertoSection5.1.2BuildingLinesandSetbacksandSection5.2AnimatingtheEdge,UK Urban Design Compendium (2000).


4.2.4 Signage and Line Marking

TheprincipalsourceforguidanceonsignageandlinemarkingistheDepartmentofTransport Traffic Signs Manual (TSM) (2010), which categorises signage and road marking intofourmaincategories:

• TSM Chapters 2 and 4: Information Signs that give directions and distances to destinations or which provide other informationthatmayberelevanttoroadusers;

• TSMChapterSection5:Regulatory Signs that give instructions, prohibitions or restrictionswhichroadusersmustobeyandindicatetheexistenceofaRoadTrafficRegulationorimplementsuchaRegulation, or both.

• TSMChapterSection6:Warning Signs are used to alert the driver to a danger or potential danger on the road ahead.

• TSM Chapter Section 7: Road Markings are definedasmarkingsonthesurfaceoftheroadforthecontrol,warning,guidanceorinformationofroadusersandmayeitherbe used on their own or to supplement associated upright signage.

Regulatory Signscanbefurtherdividedintothree main groups:

• Mandatory Signs are used to indicate that a road user must take a certain action. For Example‘Stop’,‘Yield’or‘KeepLeft’.

• Restrictive Signs to indicate a limit must notbeexceeded.ForExample‘50km/hSpeedLimit’or‘WeightLimit3tonne’.

• Prohibitory Signs to indicate something whichmustnotbedone.ForExample‘NoRightTurn’or‘NoParking’.

Theimplementationofaself-regulatingstreetenvironment means that the reliance on signage or line marking to direct or instruct peopleissignificantlyreduced.Asnotedinthe Manual for Streets (2007)8,theremayalsobetraffic-calmingbenefitsofa‘lessismore’approachtoreinforcelowerdesignspeeds.Forexample,theremovalofcentrelinemarkingshasbeenfoundtoreducevehiclespeedsandthenumberofaccidents.9 With reduced signage drivers must navigate the streetenvironmentwithfullregardtotheirownbehaviourandthebehaviourofothersaroundthem.Anemphasisonthevaluesofplacealsorequiresthevisualimpactofsignagetobe considered in order to reduce visual clutter.

The TSM warns against over providing signage andlinemarking.Section1.1.10oftheTSMstates in relation to signage in general, ‘signs shouldonlybeerectedwherethereisademonstrableneed,becauseunnecessary,incorrectorinconsistentsignsdetractfromtheeffectivenessofthosethatarerequiredandtendstoleadtodisrespectforallsigns’.Thereisalsoalimittohowmanysigns/linemarkingsdrivers can absorb in a short period.

Todefinewheredesignersareallowedtoemploydiscretion,Section1.1.12oftheTSMstates that:

• ‘Shall’or‘must’indicatesthataparticularrequirementismandatory;

• ‘Should’indicatesarecommendation;and

• ‘May’indicatesapermissibleoption.

8 RefertoSection9.1.7oftheManual for Streets (2007). DesignersshouldalsonotethattheManual for Streets recommended monitoring streets where little or no signageisusedtoconfirmitseffectiveness.

9 RefertoImprovingTraffic Behaviour and Safety Through Urban Design, Civil Engineering(2005).


Figure 4.16. Kensington High Street, London, UK, where as part of upgrade works, a major decluttering exercise took place which included removing all guardrails, minimising signage and line marking. It is notable that upon completion of the works, vehicle speeds decreased and the incidence of accidents decreased by 43% (2003-2005). Left image source: Kensington and Chelsea Borough Council.

Figure 4.15: Walworth Road, Central London, UK, before (top) and after (bottom). The street carries over 20,000 vehicles per day and as part of major upgrade signage and line marking were minimised (image source: Southwark Council).

Designersshouldusethisdiscretionwithregardtotheself-regulatingcharacteristicsofstreetsandtheimpactofsigns/linemarkingonthevalueofplacewhenapplyingtheTSM.Inthisregard:

• Minimal signage is required on Local streets due to their low speed nature and lowmovementfunction.Thegenerallylightlytraffickednatureofthesestreetsmeansthattheuseofsignagecanbeminimised, and in some cases eliminated altogether.

• TherequirementsforsignageonArterial and Link streets will be higher than on Localstreets.TheuseofsignageshouldbekepttotheminimumrequirementsoftheTSM,particularlywhereplacevaluesareveryhigh,suchasintheCentre context.

Designersmayhaveconcernsaboutminimisingsignageonstreetsthatcarryhighervolumesoftraffic,buttherearemanysuccessfulexampleswheretheamountofsignageprovidedhasbeensignificantlyreduced(seeFigures4.15and4.16).


With regard to signs and line marking more generally(seeFigure4.17):

• Signage structures should be rationalised. Individualsignpolesmaybebetterutilisedand signs should be clustered together on a single pole.10

• Non-regulatory,andinparticularInformation Signs,signagemaybeembeddedwithinstreetsurfacesorincorporatedintootheritemsofstreetfurniture.

• Local authorities should undertake periodic decluttering exercises to remove unnecessaryrepetitiveandredundantsignage.11

• ThesizeofindividualsignsshouldgenerallybetotheminimumspecificationstatedintheTSMfortheparticularspeedlimit.

• TheuseofWarning signs should be limited astheyaregenerallynotrequiredinbuilt-upareaswherepotentialhazardsareclearlylegibleandvehiclestravelatlower to moderate speeds. Warning signs shouldbeinstalledonlyifanengineeringassessmentindicatesaspecificneedforimprovingroadsafetyforusersanditisclearthatthesignwillbeeffective.12

10 RefertoAction16ofSmarter Travel (2009) which requirestherationalisationofsignagepoles

11 RefertoUKDepartmentforTransportLocal Transport Note 1/08.Examplesofguidelinesareavailablefromwww.english-heritage.org.uk

12 RefertoSections6.1.17and6.1.19oftheTraffic Signs Manual (2010).

Figure 4.17: Example of the improvements to a streetscape that can be achieved where signage and line marking are substantially reduced. Note all changes have been made within the scope of the TSM.

BEFORE AFTER

• Designersshouldminimisetheduplicationofsignageand/orroadmarking.Wheresignage and road markings provide the samefunction,preferenceshouldbegiventotheprovisionofroadmarkingsonly,unlessspecificallyrequiredbytheTSM. In general, road markings are more legiblefordriversandhavelessofavisualimpact on the streetscape.

• Theuseofsignageand/orroadmarkingthat duplicate existing regulations should beavoidedandmayleadtoconfusion.Forexampletheuseofdoubleyellowlinesaroundcornerstoreinforcethestandardprohibitiononstoppingwithin5mofaroadjunctionmayleadtomisinterpretationthatloadingisgenerallypermitted.13

DesignersshouldalsonotethataRegulatory signmaynotberequiredasa‘regulation’ora‘mandatoryrequirement’.Designersmayconclude that a Regulatory sign maynotbeneededduetotheself-regulatingnatureofthe street and/or in order to reduce the overall amountofsignageused.

13 RefertoSection7.6.5oftheTraffic Signs Manual (2010).


4.2.5 Street Furniture

Streetfurnitureservesmanypurposesthatrelatetobothplaceandfunctionandincludesavarietyofcommonlyfounditemswithin a street such as public art, lighting, bollards,guardrails,seatingandcycleparking.Whilstitemssuchaspublicartmaybeofplacevalueonly,manyotheritems,ifwelldesigned,provideaplaceandfunctionvalue(seeFigure4.18).

Ingeneral,theprovisionofstreetfurnituremustbeconsideredaspartoftheoveralldesignofstreet. In this regard:

• Theplacementofstreetfurnitureshouldbeconsideredaspartofawiderstrategy,suchaspartofanintegratedlandscapeplanorseriesofstreettypologies.

• Streetfurnitureshouldbeplacedwithina designated zone, such as a verge (see Section4.3.1Footways,VergesandStrips)

• Theitemsusedshouldbechosenfroma limited palette that promotes visual cohesion (seeSection5.2.1PolicyandPlans), while contrasting with the backgroundtoassistthevisuallyimpaired.

• Thenumberofitemsusedshouldbebalancedwithotherfacilities(includingsignage and line marking) to reduce clutter.

• Existingitemsofhistoricvaluewhichpromote local character should be clearlyidentified(seeSection4.2.8HistoricContexts).

Guardrails

An integrated approach to street design will substantiallyreducetheneedforobtrusivephysicalbarrierssuchasguardrails.Forexample,thealignmentofcrossingpointswithdesirelineswilleliminatetheneedforguardrails to redirect pedestrians (see Section 4.3.2PedestrianCrossings)

In this regard:

• Guardrailsshouldnotbeusedasatoolfordirecting and/or shepherding pedestrians.

Figure 4.18: An example from Drogheda, Co. Louth, where well placed street furniture has a functional role that also provides a major contribution to the streetscape and value of place.


Figure 4.19: Items such a bicycle racks, seating and/or bollards are less intrusive elements that can be used to guide pedestrians toward crossing points and reduce illegal kerb mounting.

• Guardrailsshouldonlybyinstalledwherethereisaprovenordemonstratablesafetybenefit,forexamplewherepeoplemayinadvertentlystepontothecarriageway(e.g. at a school entrance).14

Wherethepotentialneedforguardrailsisidentified(suchasviaaRoadSafetyAudit),designers should review their design as this needmayhighlightinadequaciesinthedesign(suchasthefailuretotakeproperaccountofpedestriandesirelines).Designersshouldalsoconsidertheuseofstreetfurniturethatmayguidepedestrianmovementandalsocontributestothesenseofplaceandprovide amenities (see Figure 4.19).

Authoritiesshouldremoveunnecessaryguardrailsonexistingstreets.Theremovalofindividualsectionsofguardrailsshouldbethesubjectofarigorousandwelldocumentedassessment process. Further guidance in regardtotheremovalofguardrailsmaybeobtainedfrom,UKGuidance on the Assessment of Pedestrian Guardrail (2012 update)andUKDepartmentforTransportLocal Transport Note 2/09 (see Figure 4.20). The National Cycle Manual (2011) also recommendstheremovalofguardrailasitposesasafetyrisktocyclists.15 Once guardrails have been removed monitoring should be undertaken to ensure the works have had the desiredeffect.

Designersmayhavesomeconcernsinregardtotheremovalofguardrailsonbusystreetsduetotheirperceptionaseffective‘crash’barriers.However,guardrailsareonlyeffectiveatstoppingvehiclesatverylowspeedsandthereforemayprovideafalsesenseofsecurityresulting in pedestrians and vehicles both payinglessattention.16

14 RefertoUKDepartmentforTransportLocal Transport Note 2/09: Pedestrian Guardrailing,forfurtherguidance.

15 RefertoSections1.1.4,4.4.1.2-4.4.1.4and4.4.4ofthe National Cycle Manual (2011).

16 RefertoUK Guidance on the Assessment of Pedestrian Guardrail (2012).

Figure 4.20: Before and after images near Kings Cross station, London, extracted from the TfL document Assessment of Pedestrian Guardrails. TfL have undertaken a wide program of guardrail removal throughout the streets of London.


Lighting

Goodqualitylightingpromotesasaferenvironmentbyensuringinter-visibilitybetweenusers.Poorlyilluminatedcarriagewaysandcyclelanescanalsomakeitdifficultforuserstoidentifypotentialhazards.Thequalityoflightingwillalsohaveamajorimpactonperceptionsofsecurity.Iflightinglevelsarenotsufficient,aplacemaynotbeperceivedassafe,particularlyforpedestriansandcyclists.Thismaydiscouragepeoplefromwalkingandcycling,particularlyinthewintermonthswhendaysareshorter,andunderminetheviabilityofpublictransport.

ThestandardsusedforlightingwithinIrelandaregenerallytakenfromBritish Standard Code of Practice for the Design of Road Lighting (BS5489).Whilstthesedocumentsshouldbereferredtoinregardtotechnicaldetails,thereare broader design considerations in regard totypeoflightingusedandthepositionanddesignoflightingcolumns.

Lighting should be designed to ensure thatboththevehicularcarriagewayandpedestrian/cyclepatharesufficientlyilluminated. On roads and streets within urban areas white light sources should be used, such as metal halide, white SON, Cosmopolis and LEDs.Whereorange(SOX)orsofterhoney(SON)colouredlightsarecurrentlyused,theyshouldbereplacedwithwhitelightaspartofanyupgrade(seeFigure4.21).

Withregardtotheheightoflightingcolumns:

• Heightsshouldbesensitivetothescaleofthe adjacent built environment.

• Incity,townandvillagestreets,alanternmountingheightinexcessof8metresisunlikelytoberequired.

• On Localstreets,andinareasofheritagesignificance,mountingheightsshouldbenogreaterthan6metres.

• Wherehighernumbersofpedestriansareactive, such as in Centres, consideration should be given to supplementing the trafficroutelightinginstallationwithalowerintensitypedestrianlightinglanternsmounted at a lower height on the same columns (see Figure 4.22). Figure 4.21: Examples of differing types of lighting

and their effectiveness in terms of safety and placemaking.

POOR(Orange SOX)

BETTER(White SON)

BEST(Metal Halide)


Lightinginstallationsshouldbegenerallylocatedwithinaverge(seeSection4.3.1Footways,VergesandStrips)and/orwithinbuild-outsthatseparatebaysofon-streetparking(seeSection4.4.9On-streetParkingand Loading). Where no verge is available, lightingshouldbelocatedatthebackoffootways,tominimiseanydisruptiontopedestrian movement provided:

• Theyarepositioned,wherepossibletocoincidewithpropertypartylinestoavoidobstructing entrances or windows.

• Theyarenotlocatedincloseproximitytopropertieswheretheymaycompromisesecurity.

On narrow streets or streets with narrow footways,considerationshouldbegiventousingwall-mountedlanterns

Lanterns should be selected and positioned so as to avoid creating obtrusive light spill on windows,particularlyinthecaseofupstairsresidential properties. Internal or external baffleplatescanbefittedtolanternstominimise nuisance light spill. Lights should alsobepositionedawayfromtrees,whichintimemaygrowtoenvelopthelanternsorcast shadows which will render the lighting less effective.

To reduce street clutter designers should consider combining lighting with other installations (see Section 4.2.4 Signage and LineMarkingandasperFigure4.22).Trafficsignal heads, small signs, bus stop signs etc. can be mounted on lighting columns with a degreeofco-operationandco-ordinationbetween the relevant authorities and service providers. CCTV columns, which need to be more rigid than lighting columns, can also accommodatelightingandotherfunctions.Ancillarylightingequipment,suchaselectricalsupplypillars,shouldalsobelocatedwitha view to minimising their impact on the streetscape, while not creating an obstruction or hazard to pedestrians. Metering cabinets inparticular,whichmaybeupto1.5metreshigh, should be located against walls, as unobtrusivelyaspossible,whilebearinginmindthattheymustbeaccessibleformaintenanceand meter reading.

Figure 4.22: Example of a light installation that is designed with both the pedestrian and the vehicle in mind and also incorporates signals for a pedestrian crossing (image source: Camden Streetscape Manual).


4.2.6 Materials and Finishes

Theuseofmaterialsandfinishesisoneofthemostdefiningelementsofastreet,particularlywhereitisusedtodefinethelevelsofsegregation and integration within a street. Thematerialpalettecandefinespace,calmtrafficandimprovelegibility,reducingtheneedforbarriers,signageandlinemarkinginfavouroftextureandcolour.Materialscanbeusedtoenhancethevalueofplaceandproducemoreattractiveandcost-effectivestreets.

Whenchoosingsurfacematerials,designersshould:

• Userobustsurfaces(suchasnaturalstone,concrete block paving or imprinted asphalt)extensivelythroughoutCentres and around Focal Points to highlight the importanceofplace,calmtrafficandalertdriversofhigherlevelsofpedestrianactivity(seeFigure4.23).

• Userobustsurfacesand/orchangesincolour around Gateways and Transitional Zonestoalertdriversofchangingdrivingconditions(seeSection3.3.4Wayfinding).

• Chooseitemsfromalimitedpalettetopromotevisualcohesion(seeSection5.2.1PolicyandPlans).

Figure 4.23: O’Connell Street, Dublin. The high place status, intensity of activity and low design speed (30 Km/h) is highlighted by high quality and robust materials, such as granite paving.

• Applyahierarchicalapproachtotheapplicationofmaterials.Alteringthepaletteaccordingtothestreethierarchyand/orimportanceofplacewillassistinwayfinding.

• Useofcontrastingmaterialsandtexturestoinformpedestriansofchangestothefunctionofspace(i.e.todemarcateverges,footway,strips,cyclepathsanddriveways)andinparticulartoguidethevisuallyimpaired(seeSection4.3.4PedestrianisedandSharedSurfaces).

Thelayoutandcolouroftactilepavingusedtoassistthevisuallyimpairedinnavigatingthepedestrian environment should ensure that a consistent logic is applied. This includes thecumulativeimpactoftactileswithothermaterial choices. For example, the use ofstrongredoryellowtactilepavingmaynot be appropriate to avoid visual clutter associatedwithtoomanysurfacetypesor colours. In such instances an approach whichbalancestheneedforvisualcontrast(toaidthevisuallyimpaired)whilstpromotingvisualcohesionispreferable(seeFigure4.24).FurtherguidanceontheuseoftactilepavingmayalsobetakenfromSection13.3oftheTraffic Management Guidelines(2003)andthe UK Guidance on the use of Tactile Paving Surfaces (2005).


HIGHER DENSITY

HIGHER ACTIVITY

HIGH

ER

AMENITYHIGHER DENSITY

HIGHER ACTIVITY

HIGH

ER

AMENITY

HIGHER

HIGHEST

HIGHHIGH

HIGH

HIGHER HIGHER

STANDARD STANDARD

Figure 4.25: Diagram illustrating a hierarchical and cost-effective approach to the specification of materials on streets.

Designersmayhaveconcernsinregardtothe initial costs associated with using higher specificationmaterialsandtheirongoingmaintenance.Theuseofhigherqualitymaterialshaswideeconomicbenefits.Forexample, in relation to shopping streets, research in the UK has shown that streets finishedwithbetterqualitymaterialsresultinbetter market prices, better rents and better retail sales.17 Capital costs should also be measuredagainstsavingsthatresultfromareductionintheneedforbarriers,signage,line marking and longer term costs related todurabilityandmaintenance.FurtherguidancemaybeobtainedfromAdvice Note 2 - Materials and Specifications and the Natural Stone Surfacing - Good Practice Guide (SCOTS Guide) (2004) .

Thequalityofmaterialsmayalsobeselectedtoensurethatmorerobustandhigherqualitymaterialsareusedwheretheyaremostneededandappreciated.Figure4.25fromthe Adamstown Street Design Guide (2010) providesanoverviewofhowthestandardofmaterialsmaybeappliedwithregardtoamenity,densityandactivity.WhenappliedsystematicallyitdirectsthedesignerstousethehighestspecificationsofmaterialsintheCentres and along streets which are the most active, such as Arterial and Link streets. It will alsodirecttheuseofhigherspecificationmaterialstothevicinityofFocal Points. Goodresultsmayalsobeachievedonlowerbudgets, provided material selection has the desiredeffectofsupportingothermeasuresaimedatcalmingtrafficanddefiningplace(seeFigure4.26).

17 RefertoPaved with Gold (2007).

Figure 4.24: Example form Drogheda, Co. Louth, of red tactile paving at a zebra crossing which has been toned down to balance the degree of contrast with higher specification materials.

Figure 4.26: Fade Street, Dublin City Centre. To reduce the overall cost of work in remodelling the street, lower budget materials such as HRA with coloured aggregate chips and epoxy resin bound surfaces were used on the carriageway and footpath, respectively.


4.2.7 Planting

Plantingisgenerallylocatedinareassuchasmedians,verges,build-outsandprivacystrips.Landscapingistraditionallyusedtoaddvalueto places though visual enhancement. There aremanyapproachesthatcanbetakenwithregardtoplanting,forexample:

• Within Centres agreateremphasismaybeplacedonusing‘harder’landscapeelementsthatdefinethemasurban,allowgreaterfreedomofmovementandareabletowithstandhigherlevelofpedestriantraffic(seeFigure4.27).

• In Neighbourhoods and Suburbs a greater emphasismaybeplacedontheuseofplantedmaterialstopromote‘softer’landscapeelementsandagreener‘living’character(seeFigure4.28).

Otherkeyconsiderationsincludetheongoingmaintenanceandsizeofstreettrees/plantingatmaturity.Qualityandmaintenanceshould be viewed in a similar regard to the applicationofmaterialsandfinishes(asperFigure 4.27) with a hierarchical approach that promotestheuseofhigherqualityplantingwithin Centres and along streets which are the most active, such as Arterial and Link Streets, and around Focal Points.

Figure 4.27: Example from Dundalk of an area with higher activity, the use of planted materials will be more sparsely and selectively applied in favour of more robust and durable materials.

Figure 4.28: Example of a residential character, a rich palette of planted materials will enhance green qualities.


Designersshouldalsoconsiderthesizeoftrees,shrubsandotherlandscapeelementsatfullmaturity.Ingeneraldesignersshouldavoidplanting that will grow to obstruct movement and surveillance. There are exceptions to this,forexampleovergrownmedianscanhelpreinforcenarrowercarriagewaysandtallshrubsmaydeflectsightlinesreducingforwardvisibility. Streets also support an important drainage functionwithinbuilt-upareas.TheshifttowardsustainableformsofdevelopmenthasseentheemergenceofSustainableUrbanDrainage(SUDs)systems.SUDsconsistofarangeofmeasuresthatemulateanaturaldrainage process to reduce the concentration ofpollutantsandreducetherateandvolumeofurbanrun-offintonaturalwatersystems(and thus the pollutants it carries). The incorporationofSUDselementsintothefabricofthestreetitselfcanalsoservetoincreaselegibilityandaddvaluetoplace(seeFigure4.29). Further advise with regard to the use ofSUDsmaybefoundintheGreater Dublin Strategic Drainage Study (2005).

Figure 4.29: Examples of Sustainable Urban Drainage incorporated into a street in the form of a small ‘swale’ (top) and larger linear basin (bottom). These treatments not only assist in containing urban surface water run-off but also contribute to the sense of place by adding a unique feature.


4.2.8 Historic Contexts

Additional design considerations must betakenintoaccountinareasofhistoricsignificancethatarehighlysensitivetointerventions.Historicfeatureshelpreinforceanareascharacter/placevalueandmayalsoplayaroleinmanagingspeeds(seeFigure4.30).Themostappropriatecourseofactionshouldbetominimiseanylevelofinterventiontoexistinghistoricalfeatures. Elementsofstreetfurnitureassociatedwiththehistoricuseofthestreetshouldbeidentifiedand protected, where appropriate (see Figure 4.31).Significanthistoricfeaturesmayalsoincludethestreetsurfaceitself(asperFigure4.30)18andanyfeaturessetintoitsuchascoalhole covers, weighbridges, pavement lights, cellar doors etc.

An‘assessmentofsignificance’shouldbeprepared when dealing with interventions within historic core areas. This is seen as addressing/acknowledging essential elements ofthehistoricurbanenvironmentwhichmayhave architectural, historical and technical significance.Forexamplewhendealingwithanestablishedstreetlayoutandassociatedmaterials a distinction is drawn between three levelsofsignificance:

1. Undisturbedareasofexistinghistoricstreets, which have the highest value andbearwitnesstotheskillofhistoriccraftsman;

2. Areas where streets have been altered orreconfiguredusingtheoriginaldesign/material;

3. Reinstatedstreetareasre-usingsalvagedmaterialfromotherplaces.

Themechanismfortheprotectionofhistoricareasisbasedonstatutoryprotection.Ifanarea lies within an Architectural Conservation Area(ACA)orformspartofthesettingofaprotectedstructure(oranumberofprotectedstructures), development policies will be set outintherelevantCounty/CityDevelopmentPlan,aswellasactiveplanningcontrol.19

18 Refer to Paving: the Conservation of Historic Ground Surfaces.Forthcomingin2013.DepartmentofArts,HeritageandtheGaeltacht.’

19 ReferalsototheArchitectural Heritage Protection Guidelines for Planning Authorities (2011).

Figure 4.30: The stone sett paved carriageways of Temple Bar, Dublin, are of historical significance, enhance the areas value as a cultural corner and calm traffic by creating a sense of shared space.

Figure 4.31: An example of a historic water fountain in Newcastle, Co. Dublin. Such features are integral of local identity and should be retained.


Figure 4.32: Illustration of the area generally thought of as the footpath. This area should be viewed and designed as three areas of activity.

Strip Footway Verge

Figure 4.33: Example from Castlebar, Co. Mayo, where the verge acts a designated space for street furniture, lighting facilities and planting of trees, keeping the footway clear of obstacles.

4.3 Pedestrian and Cyclist Environment

4.3.1 Footways, Verges and Strips

Astrongsenseofenclosureandactivestreetedgescontributetoapedestrians/cyclistssenseofsecurityandcomfortbycreatingstreets that are overlooked, animated and shelteredfrominclementweatherconditions.Studieshavefoundthatprovidingwiderandbetterqualitywalkingfacilitiescanleadto an increase in walking.20 Well designed footpathsarefreeofobstaclesandwideenough to allow pedestrians to pass each otherincomfort.Forthispurposethefootpathisdividedintothreeareas(seeFigure4.32):

• Footway:thisisthemainareaalongwhichpeople walk.

• Verges:Theseprovideabufferbetweenpedestriansandthevehiclecarriagewayandprovidespaceforstreetfurnitureandstreettreesaswellasoverflowspaceforpedestrianmovement(seeFigure4.33).

• Strips:Thesespaces,provideddirectlytothefrontofabuilding,maybeoccupiedbyactivitiesgenerallyassociatedwithretail/commercial uses such as stalls oroutdoorseating.Stripsmaybeincorporatedintotheprivatespaceofadwelling(asperFigure4.13).

20 RefertoSection5.1oftheUK Manual for Streets 2 (2010).

Footways

Minimumfootwaywidthsarebasedonthespaceneededfortwowheelchairstopasseachother(1.8m).Indenselypopulatedareas and along busier streets, additional width must be provided to allow people to pass each other in larger groups. In this regard:

• ThewidthoffootwaysshouldincreasefromSuburbs (loweractivity),toNeighbourhood (moderateactivity)andtoCentres (higher activity)andasdevelopmentdensitiesincrease.

• ThewidthoffootwaysshouldincreaseaccordingtofunctionfromLocal (lower activity),Link (moderateactivity),toArterial streets (moderate to higher activity)asconnectivitylevelsincrease.

• Thefootwayshouldbemaintainedataconsistent width between junctions and should not be narrowed to accommodate turning vehicles.

Figure4.34illustratesthespaceneededforpedestrianstocomfortablypasseachotherwithreferencetotheanticipatedlevelsofactivitywithinastreet.Thesestandardsshouldbeusedtoformulatetheminimumfootwaywidths.


Figure 4.34: Diagram showing the amount of space needed for pedestrians to pass each other with regard to pedestrian activity levels.

PEDESTRIAN ACTIVITY AND FOOTWAY WIDTH

Minimumspacefortwopeopletopasscomfortably.Areasoflowpedestrianactivity

1.8m

Desirablespacefortwopeopletopasscomfortably.Areasoflowtomoderatepedestrian

activity

2.5m

Minimumspaceforsmallgroupstopasscomfortably.Areasofmoderatetohigh

pedestrianactivity

3.0m

Minimumspaceforlargergroupstopasscomfortably.Areasofhighpedestrianactivity

4.0m

Inareasofparticularlyhighpedestrianactivity,such as shopping streets or close to major nodes (such as a train station) more complex modellingmaybeneededtodeterminefootwaywidths.InsuchcasesdesignersmayrefertotheUKPedestrian Comfort Guidance for London(2010)forfurtherguidanceinregardtofootpathwidthsbasedonthevolumeofpedestriansperhour(providedthesedonotfallbelowthethresholdsinFigure4.34).Thisguidancemayalsobeofparticularassistanceinassessingpedestriancomfortlevelsonexistingfootways.

Inaretrofitsituationincreasingfootpathwidthsshouldbeapriorityfordesignersandwhereappropriate,accommodatedbynarrowingvehicularcarriageways(seeSection4.4.1CarriagewayWidths).Increasesinwidthshouldalsobeconsideredaspartofapackageoffacilities,includingtheprovisionofcyclelane/tracks,on-streetparkingandotherstreetfacilities(includingstreettrees).

Designersshouldalsoensurethatthedesignofvehiclecrossoversclearlyindicatethatpedestriansandcyclistshavepriorityovervehicles. There should be no change in level tothepedestrianfootwayandnouseofasphalt(whichwouldincorrectlyindicatevehicularpriorityacrossafootpath).Largeorbusydriveways(i.e.accesstolargecarparks)may,however,bedemarcatedbyachangeinsurfacematerials,suchascontrastingpaving and/or coloured concrete (see Figure 4.35).DesignersshouldalsorefertoSection5.4-EntrancesandDrivewaysoftheNational Cycle Manual (2011)forfurtherdesignguidancewherecycletracksarepresent.

Verges

Theneedandsizeofthevergewilllargelybedependentonthefunctionofthestreetandthepresenceofon-streetparking.Ingeneral:

• On Arterial and Link streetswithnoon-streetparkingavergeof1.5-2mshouldbeprovidedasabufferandtofacilitatetheplantingoflargestreettreesanditemsofstreetfurniture.


• Thereisnominimumrequirementforverges on LocalStreets,butdesignersmayneedtoprovidespacetopreventanyencroachmentofstreetfurnitureintothefootway.

• Whereon-streetparkingisprovided,averge(andchangeinkerbline)maybeneeded on approaches to junctions to enforcethevisibilitysplays(seeSection4.4.5VisibilitySplays).Insuchcasesthewidthofthevergewillgenerallycorrespondtothewidthofcarparkingspaces.

• Avergeshouldbeprovidedwherecycletracks are located adjacent to parking spaces(seeSection4.3.5CycleFacilities)

• Averge(minimumof0.3m)shouldbeprovidedinareasofperpendicularparkingwherevehiclesmayoverhangthefootway(seeFigure4.36)

Figure 4.36: An example where a narrow verge is provided to ensure that vehicle overhangs do not intrude on the footway.

Figure 4.35: Example from Dublin where pedestrian priority across driveways is indicated by maintaining footway levels and surface treatments.

Strips

Stripsmaybeprovidedasadesignatedzonethatfurtheranimatesthestreetand,inthecaseofaresidentialproperty,provideabufferbetweenthefootwayandtheprivateresidence.

Withregardtoareasofcommercialactivity:

• Where outdoor seating is provided the minimumwidthofastripshouldbe1.2m.

• Outdoorseatingmayalsobeprovidedwithinavergearea,wherethefootwayrunsbetweentheshopfrontandseatingarea.

• There is no recommended maximum size ofastrip,butthedesignteamshouldconsidertheimpactoflargersetbacksonthesenseofenclosureofthestreetifalarge area is proposed.

• Adesignatedstripmayalsobeconsideredwithin Centres on shopping streets to provideadditionalspaceforwindowshopping.

ForresidentialareasdesignersshouldrefertoSection4.2.3ActiveStreetEdges,withregardtothewidthofprivacystrips.


4.3.2 Pedestrian Crossings

Crossingsareoneofthemostimportantaspectsofstreetdesignasitisatthislocationthat most interactions between pedestrians, cyclistsandmotorvehiclesoccur.Welldesignedandfrequentlyprovidedcrossingsarecriticaltothebalancingofmovementpriorities.Thedesignofcrossings,andthefrequencyatwhichtheyareprovided,willhaveasignificantimpactonpedestrian/cyclistmobilityandcomfortandtheflowofvehiculartraffic.

Crossing Selection

Crossingsarereferredtoascontrolled,such as zebra or signalised crossings or uncontrolled.21 Uncontrolled crossings include lessformaltypessuchascourtesycrossingsand/orthoseidentifiedbyadropkerb.Atjunctionlocationsthetypeofcrossingusedwillgenerallybedeterminedinconjunctionwiththeformofjunctioncontrolthatisusedtomanagetraffic(seeSection4.4.3JunctionDesign).Moregenerally,designersshouldbeguidedbypedestriandemands,safetyandvehicleflows.Inthisregard:

• In general, signalised crossings should be providedonbusyArterial and Link streets and/orwherecyclistsarelikelytocross.

21 RefertoSection12.3-12.4oftheTraffic Management Guidelines(2003).

• Zebra crossings provide pedestrian priorityandmaybeusedwhereformalcrossingfacilitiesaredesirable,howeverafullysignalisedcrossingisnotneeded.ExamplesmayincludeonArterial and Link streets within lower speed environments, such as Centres(seeFigure4.37) and/orwherebothlevelsofpedestrianandvehicularactivityaremoremoderate.22

• Courtesycrossings,whicharegenerallydefinedbyachangeinmaterialand/orverticaldeflection(seeSection4.4.7HorizontalandVerticalDeflections),allowpedestrianstoinformallyassertadegreeofpriorityoverdrivers.Theymaybeused in lower speed environments where formalcrossingfacilitiesarenotrequiredtoassistinmakingsuchenvironmentsselfregulating,seeFigure4.38.

• Localstreets,duetotheirlightly-trafficked/low-speednature,generallydonotrequiretheprovisionofcontrolledcrossings.Theprovisionofdropkerbswillgenerallysuffice.Howeverzebracrossingsorcourtesycrossingshouldbeconsideredwhere pedestrian demands are higher such as around Focal Points.

22 RefertoSection12.3oftheTraffic Management Guidelines (2003).

Figure 4.38: Example of an informal ‘courtesy’ crossing in Westport, Co. Mayo. Drivers stop and wait for pedestrians to cross as a courtesy.

Figure 4.37: Example of a Zebra crossing within the town centre of Dundalk, Co. Louth. Zebra crossings promote greater levels of pedestrian priority as drivers must give way to pedestrians once they have commenced the crossing.


Figure 4.39: Example of a wide streets with a crossing that allows pedestrians to cross in a direct manner and in a single movement. The median acts as a refuge island for those users who cannot cross the street in a reasonable time.

Crossing Design and Waiting Times

Smarter Travel (2009) requires that pedestrian movement at signalised crossings be given prioritybytimingtrafficsignalstofavourpedestriansinsteadofvehiclesbyreducingpedestrian waiting times and crossing distances at junctions.23 To achieve this objective, designers should:

• Optimise pedestrian movement, with pedestriancycletimesofnomorethan90secondsattrafficsignals.

• Allow pedestrians to cross the street in a single,directmovement(seeFigure4.39).Staggered/staged crossings should not be used where pedestrians are active, such as in Centres, Neighbourhoods and Suburbs (except where stated below).

• Where staggered/staged crossings currentlyexisttheyshouldberemovedaspartofanymajorupgradeworks.Thisshould include realignment works to slow vehicle movements, such as reduced cornerradiiand/orcarriagewaynarrowing(seeFigure4.40andSection4.3.3CornerRadii)

23 RefertoAction16of Smarter Travel (2009).

Crossing Locations

Thelocationandfrequencyofcrossingsshouldalignwithkeydesirelinesandbeprovidedat regular intervals. Within larger areas this mayneedtobeaddressedviaaspatialanalysisandsupportingplan(seealsoSection5.2.1PlansandPolicies).Methodsthatrelyonabsolutefigures,suchasthesystemofwarrants,shouldnotbeused.Moregenerally,designers should:

• Providepedestriancrossingfacilitiesatjunctionsandoneacharmofthejunction.

• Minimise corner radii so that crossing points are located closer to corners on pedestriandesirelines(seeSection4.3.3Corner Radii).

• Provideregularmidblockcrossingsinareasofhigherpedestrianactivity,suchas Centres, where the distance between junctions is greater than 120m.

• Locatemid-blockcrossingsatstrategiclocationswherepedestriansarelikelytocross, such as adjacent to bus stops and Focal Points,ortocoincidewithtraffic-calming measures on longer straights (see Section 4.4.7 Horizontal and Vertical Deflections).


Designersmayhaveconcernsregardingtheomissionofstaggered/stagedcrossingsonwidestreets(i.e.withfourormorelanesandamedian)onthegroundsofsafetyandtrafficflow.Withregardtosafetytheseconcernsmaybeovercomeby:

• Ensuringenoughgreentimeisprovidedforpedestrians to cross in a single movement.

• Removingflashingamberlightsphaseswherevehiclesmaymoveforwardnotrealising pedestrians are still on the median orfarsideofthecrossing.

• Providingbuild-outs,wherepossible,toreduce the crossing distance.

• Providingarefugeisland(minimumof2m)forthosewhoareunabletomakeitallthewayacrossinareasonabletime.UndersuchcircumstancesaPushButtonUnit(PBU)andtherequiredsignalsmustbeprovidedwithintherefuge.

Safetyconcernsregardingpedestriancrossings should also be viewed in the contextofpedestrianbehaviour.Researchhasfoundthatpedestriansarelesslikelytocomplywiththedetour/delaycreatedbystaggeredcrossings,leadingtounsafecrossing behaviour.24Itwillgenerallybemoredesirable,fromasafetypointofview,toprovide a direct single phase crossing.

24 RefertoPedestrian Crossing Behaviour at Signalised Crossings(2008).

Withregardtotrafficflowonwidestreetsamoreflexibleapproachmaybetakenwheretrafficmodellingconfirmsthatjunctionswouldbecomeoverlysaturatedforlongperiodsifdesigned with single phase/direct pedestrian crossings. A judgement will need to be made astheremaybecircumstanceswhereitisacceptable to saturate junctions in order to prioritise/promote more sustainable travel patterns(seeSection3.4.2TrafficCongestion)Inthesecircumstancesdesignersmayalsoconsider:

• A straight ahead two stage crossing within lower speed environments where themedianissufficientlywidetoclearlydistinguisheacharmofthecrossing.

• Increasepedestriancycletimesupto120secondsforshortorintermittentperiods(i.e.whensaturationislikelytooccur).

• Implement more conventional staggered crossingswherethebalanceofplaceandmovement is weighted toward vehicle movement such as on Arterial streets in Suburban areas or morebroadlyinIndustrial Estates and the Rural Fringe. Whereapplied,thewidthofthecentralareaforpedestriancirculationshouldbeaminimumof2m.

Figure 4.40: Example from Kensington High Street, London, of a left hand turning slip point was removed and replaced with a safer single phase crossing which also slowed vehicle turning movements (image source: Hamilton Baillie).

BEFORE AFTER


WhendeterminingthewidthofcrossingsdesignersshouldrefertoSection7.16oftheTraffic Signs Manual (2010) which contains maximumandminimumdesignspecificationsforpedestriancrossings.Inthisregard(seeFigure 4.41):25

• Within Centres and on Arterial streets, all crossingsshouldgenerallybeaminimumof4mwide.

• Theminimumwidthofallotherpedestriancrossings should be 2m.

• TheminimumwidthforToucancrossingsshould be 4m.

• Indeterminingtheoptimalwidthofapedestriancrossing,designersmayrefertoFigure4.34toensurethatpedestriansareabletopasseachotherincomfort.

• Oncrossingswhereveryhighnumbersofpedestriansand/orcyclistscross,awidthinexcessofthoseabovemayberequired,toamaximumof10m.

ItisalsoanobjectiveofSmarter Travel (2009) that level grade crossings (i.e. those that arealignedwiththeheightoffootways)beprovidedforpedestriansacrossjunctions.26 ThesearehighlyrecommendedinareaswherepedestrianflowsarehighsuchasinCentres.Theyarealsoaneffectivemeasureforcalmingtrafficandenforcinglowerspeeds(See Section 4.4.7 Horizontal and Vertical Deflections).

25 RefertoSection7.16oftheTraffic Signs Manual (2010) which contains maximum and minimum design speci-ficationsforpedestriancrossings.

26 RefertoAction16ofSmarter Travel (2009).

Figure 4.41: Standard crossing widths to be used in most circumstances across the main carriageway of Access or Link streets and across side junctions with Local streets.

Min 4.0m

Min 2-3m


4.3.3 Corner Radii

Reducingcornerradiiwillsignificantlyimprovepedestrianandcyclistsafetyatjunctionsbylowering the speed at which vehicles can turncornersandbyincreasinginter-visibilitybetween users (see Figure 4.42). Reduced cornerradiialsoassistinthecreationofmorecompact junctions that also align crossing points with desire lines and reduce crossing distances. Cornerradiusisoftendeterminedbysweptpathanalysis.Whilstsweptpathanalysisshould be taken into account, designers needtobecautiousastheanalysismayoverestimatetheamountofspaceneededand/or the speed at which the corner is taken. Furthermore,suchanalysisalsotendstocaterforthelargevehicleswhichmayonlyaccountforrelativelyfewmovements.

Figure 4.42: Illustration of the benefits of reduced corner radii on pedestrian and cyclist safety (images based on Figures 6.3 and 6.15 of the UK Manual for Streets (2007)).

Fastermovingvehicleatedgeof/outsideofpedestriansperipheralvision.

Slower moving vehicle within pedestrians peripheral vision. Reduced crossing distance.

Vehicleandcyclistspeedismorecompatible.

Increaseddangerfromfastermovingvehiclecuttingacrosscyclist.

LARGER CORNER RADII REDUCED CORNER RADII

Designersmustbalancethesizeofcornerradiiwithuserneeds,pedestriansafetyandthepromotionofloweroperatingspeeds.Inthisregarddesignersmustconsiderthefrequencywithwhichlargervehiclesaretobefacilitatedasfollows(seeFigure4.43):

• In general, on junctions between Arterial and/or Link streets a maximum corner radii of6mshouldbeapplied.6mwillgenerallyallow larger vehicles, such as buses and rigidbodytrucks,toturncornerswithoutcrossingthecentrelineoftheintersectingroad.27

27 RefertoSections6.9,9.3and10.4ofthe Traffic Management Guidelines (2003).


• WhereturningmovementsoccurfromanArterial or Link street into a Local street cornerradiimaybereducedto4.5m.

• Where design speeds are low and movementsbylargervehiclesareinfrequent,suchasonLocal streets, a maximumcornerradiiof1-3mshouldbeapplied.

• In circumstances where there are regular turningmovementsbyarticulatedvehicles,thecornerradiimaybeincreasedto9m(i.e. such as in Industrial Estates).

Designersmayhaveconcernsregardinglargervehiclescrossingthecentrelineoftheintersecting street or road. Such manoeuvres are acceptable when turning into/or between LocalorlightlytraffickedLink streets as keepingvehiclespeedslowisofhigherpriority.Wheredesignersfinditdifficulttoapplytheradiireferredtoabove,ortofurtherreducecornerradiiwherepedestrianactivityishigh(suchaswithincentres)designersmayalso:

• Increasethecarriagewaywidthat junctions to provide additional manoeuvrabilitywithoutsignallingtodrivers that the corner can be taken at greater speeds (see Figure 4.44).

X

X+

Figure 4.44: Illustration of how tighter corner radii can be applied to a junction, with additional manoeuvrability for larger vehicles provided by widening the street entrance.

Figure 4.43: Approaches minimising corner radii according to level of service by larger vehicles.

Few larger vehicles

1-3m

Frequent larger vehicles

9m

Occasional larger vehicles

4.5-6m

CORNER RADII


• Applysetbackvehicularstoplinesatsignalised junctions to allow turning vehiclestocrossthecentrelineoftheintersectingstreetwithoutconflictingwithoncomingmovements(seeFigure4.45andSection4.4.2oftheNational Cycle Manual (2011)).

• Designersshouldalsoconsidertheuseofsetback stop lines on Arterial and Links streetswithincentrestofurtherreducecorner radii.

• Keepingcornersclearofobstacles(orremoving obstacles such as guardrails) to allowemergencyvehicleoverrun.

Figure 4.45: Setback stop lines allow for additional vehicular manoeuvrability for larger vehicles at signalised junctions without the need for larger corner radii.


4.3.4 Pedestrianised and Shared Surfaces Pedestrianisedandsharedsurfacesareaneffectivewayofpromotingplaceandprovidingpedestriansandcyclistswithamoreenjoyableexperience,particularlyinareasofhistoricsignificance.Thesestreetsoperateaslinear‘squares’orcorridorsofpublicopenspace.

Pedestrianisedstreetsfullysegregatepedestriansandcyclistsfrommotorvehicularmovement(althoughemergencyaccessispossibleandlimitedaccessmayalsobeprovidedforservicevehicles).Theyaregenerallyonlyappropriateinareaswherehigherlevelsofactivitycanbesustainedthroughoutthedayandintotheeveningperiod,astheremovalofvehiculartrafficwillreducesurveillancelevels.Theyarebestsuited to the Centresaroundareasofretail,commercialandculturalactivity(seeFigure4.46).

Sharedsurfacestreetsandjunctionsareintegratedspaceswherepedestrians,cyclistsandvehiclessharethemaincarriageway.Thismayincludestreetswheretheentirestreet reserve is shared (see Figure 4.47) or wheredesignatedsectionsmayprovideforpedestriansand/orcyclistsuseonlywithasharedsurfacecarriagewayalongpartofthestreet(seeFigure4.48).Sharedsurfacestreetsmayalsoperiodicallytransferfrompedestrianonlyspacestosharedspacesatdifferenttimesoftheday(asperFigure4.47).

Sharedsurfacestreetsandjunctionsareparticularlyeffectiveatcalmingtraffic.Researchhasfoundthatsharedcarriagewaysperformwellintermsofsafetyandthereisalso evidence to suggest that well designed schemes in appropriate settings can bring benefitsintermsofvisualamenity,economicperformanceandperceptionsofpersonalsafety.28

Sharedsurfacestreetsandjunctionsarehighlydesirable where:

• Movement priorities are low and there is a high place value in promoting more livable streets (i.e. homezones), such as on Local streets within Neighbourhood and Suburbs.

28 RefertoUKDepartmentforTransportShared Space Project Stage 1: Appraisal of Shared Space (2009).

Figure 4.46: Fully pedestrianised street within a Centre. Activity is sustained by a mix of retail, commercial and cultural activities.

Figure 4.48: Exhibition Road, London, an example where distinct zones that delineate pedestrian only space from shared space have been created (image source architects).

Pedestrian Only Zone

Shared Zone

Figure 4.47: Street in Waterford City Centre which changes from a pedestrianised space to a shared surface area at different times of the day.


• Pedestrianactivitiesarehighandvehiclemovementsareonlyrequiredforlower-levelaccessorcirculatorypurposes.Thisinclude streets within Centres where a sharedsurfacemaybepreferableoverfullpedestrianisationtoensuresufficientactivityoccursduringthedaytimeandtheevening period.

Theapplicationofsharedsurfacesmayalsobedesirableonawidevarietyofstreetsandjunctions.TheimplementationofsharedsurfacesintheUKandinternationallyhasevolvedfromlightly-traffickedareastoincludeheavily-traffickedstreetsandjunctions(asperFigure4.48andFigure4.49).Wheredesignersconsidertheuseofsharedsurfacesonmoreheavily-traffickedroutesthelocationmustbethesubjectofarigorousanalysisthatassessesthesuitabilityofastreetforsuchpurposes.

Thekeyconditionforthedesignofanysharedsurfaceisthatdrivers,uponenteringthestreet,recognisethattheyareinasharedspaceandreactbydrivingveryslowly(i.e.20km/horless). To ensure this, designers should:

• Useavarietyofmaterialsandfinishesthatindicatethatthecarriagewayisanextensionofthepedestriandomain(suchaspaving:seeSection4.2.6-Materialsand Finishes).

Figure 4.49: Shared surface junction in Ashford, Kent, UK, carries significant amounts of traffic and challenged conventions regarding traffic volumes along shared surfaces. An informal zebra crossing has also been marked adjacent to the junction to provide a place for less confident pedestrians to cross.

• Avoidraisedkerblines.Anykerblineshouldbefullyembeddedwithinthestreetsurface(seeSection4.4.8Kerbs).

• Minimisethewidthofthevehicularcarriagewayand/orcornerradii(seeSections4.3.3CornerRadiiand4.4.1CarriagewayWidths).

Sharedsurfacestreetscanbeveryintimidatingforimpairedusers.Visually-impairedusersinparticularusuallyrelyonkerblinestonavigatestreets. To assist navigation and movement throughsharedspaces,designersshouldapplydesign measures such as:

• Sectionsoftactilepavingthatdirectmovement along the street or across spaces(seeFigure4.50).

• Thecreationofdistinctzonesthatdelineatepedestrianonlyspacefromsharedspace(asperFigure4.48).

• Flush kerbs, drainage lines and/or sections oftactilepavingtoassistguidedogsandindicatemovementfromapedestrianonlyspacetoasharedcarriageway(seeSection4.4.8Kerbs).


Figure 4.51: Examples from Adamstown, Co. Dublin, where a verge is provided as refuge that pedestrians can hop on and hop off as cars slowly pass.

• Vergesthatactasrefugezonesallowingpedestrianstosteponandoffthecarriagewaytoletcarspass(seeFigure4.51).

Figure 4.50: Examples from Cork city of the use of tactile paving that assist the visually impaired by guiding movement across a shared space.


Figure 4.52: Extract from the National Cycle Manual (2011) which illustrates the appropriate use of integrated or segregated cycle facilities according to the volume and speed of traffic.

4.3.5 Cycle Facilities

This Manual and the National Cycle Manual (2011)(NCM)promotecyclingasasustainableformoftransportandseektorebalancedesignprioritiestopromoteasaferandmorecomfortableenvironmentforcyclists.Toachieve these goals, the NCM recognises the importanceofslowingvehiculartrafficwithincites, towns and villages, and advocates manyofthemeasurescontainedwithinthis Manual, such as narrower vehicular carriagewaysandtightercornerradii.

TheprinciplesourceforguidanceonthedesignofcyclefacilitiesistheNCMpublishedbytheNationalTransportAuthority.TheNCMprovides designers with a comprehensive set ofdesignmeasuresaimedatachievinganoverallqualityofservicethatisappropriatetouser needs.

Figure4.52,fromtheNCM,providesanoverviewoftheintegrationandsegregationofcycletrafficwithinthecarriagewaybasedonvehiclespeedsandtrafficvolumes.Forexample:

• Onlightly-trafficked/low-speedstreets,designersaregenerallydirectedtocreateShared Streetswherecyclistsandmotorvehiclessharethecarriageway

• On busier/moderate speed streets, designersaregenerallydirectedtoapplyseparatecyclelanes/cycletracks.

Designersmustalsohaveregardtothemeasures contained within this Manual when applyingtheNCM.Forexample:

• Tominimisethewidthofvehicularcarriagewaysfromkerbtokerb,preferenceshouldbegiventotheimplementationofRaised Cycle Lanes or Raised Cycle Tracks over those design solutionswherecyclistsandvehiclesareatgrade.


Figure 4.53: Example of a narrow verge between a cycle track and on-street parking. This verge provides a buffer that protects cyclists from opening doors.

0.75-1.0m

• CyclefacilitiesonmoststreetswithinCentres, Neighbourhoods and Suburbs willneedtobeintegratedwithon-streetparking.Pages138-139and149oftheNCM illustrate how this can be achieved withCycleLanes.Figures4.53and4.54illustratethiswithregardtoaCycleTrack.

• Toreduceclutter,theuseofhatching,

bollards and signage associated with cyclefacilitiesshouldbeminimisedwithinareas with a higher place value such as Centres, Neighbourhoods and Suburbs. Asimilarlogicmaybeappliedinrespectoftherequirementsforsignageandline marking within the NCM as with the applicationoftheTraffic Signs Manual (2010),referSection4.2.4SignageandLineMarking.

TheNCMalsomakesseveralreferencestothe Traffic Management Guidelines(2003).Asthe Traffic Management Guidelines precede thisManualmanyofthesereferencesmaynolongerberelevantanddesignersshouldreferto the corresponding principles, methods and standards contained within this Manual.29

29 ForcomparisonbetweentheroadclassificationsystemusedwithintheNational Cycle Manual (2011) and Traffic Management Guidelines (2003) designers shouldrefertoTable3.1.

Figure 4.54: Extract from page 86 of the National Cycle Manual illustrating how to re-establish from an Off Road Cycle Track to Cycle Lane on approach to a junction. This design can be adapted to cater for on-street parking by placing spaces within the green area or verge between the vehicular carriageway and Cycle Track.


4.4 Carriageway Conditions

4.4.1 Carriageway Widths ResearchfromtheUKhasfoundthatnarrowcarriagewaysareoneofthemosteffectivedesignmeasuresthatcalmtraffic.30 The width ofthevehicularcarriagewayismeasuredfromkerbtokerborfromtheoutsidelineofaCycleLaneorfromtheedgesofparkingspaces(wherethelatterfacilitiesareprovided).

Designersshouldminimisethewidthofthecarriagewaybyincorporatingonlyasmanylanesasneededtocaterforprojectedvehicleflowsandbyreducingthesizeofindividuallanes to meet predominant user needs (see Figure4.55).Inthisregard: • In new designs the standard lane width

on Arterial and Link Streets should lie in the rangeof2.75mto3.5m.Withinthisrangethepreferredvaluesare3.0mand3.25m.The selected values within the overall rangewilldependonthefollowing:

- thefunctionandcontextofthestreet- thenumberoflargevehiclesusingthe street- accessrequirementsandfrequencyof accesses- theoverallnumberoflanes- theneedforlanewidthreductionsat pinch points

• ThestandardcarriagewaywidthonLocal streetsshouldbebetween5-5.5m(i.e.withlanewidthsof2.5-2.75m).

• Where additional space on Local streets is needed to accommodate additional manoeuvrabilityforvehiclesentering/leaving perpendicular parking spaces, this should be provided within the parking bayandnotonthevehiclecarriageway(seeSection4.4.9On-StreetParkingandLoading).

• ThetotalcarriagewaywidthonLocal streetswhereasharedsurfaceisprovidedshouldnotexceed4.8m.

30 RefertoFigure7.16ofUK Manual for Streets (2007).

Onheavily-traffickedArterial and Link streets withmultiplelanes(seeSection3.4.5NoiseandAirPollution)inurbanareasdesignersshould consider the street as Boulevard with a median that is no less than 2m wide to provide areasofpedestrianrefugeandallowfortheplantingoflargetrees.

Whencarryingoutupgrades,ortraffic-calmingworksonexistingstreets,thefirstpriorityofauthoritiesshouldbetonarrowexistingcarriagewayswheretheyexceedthosestandardslistedabove.Thiswillnotonlycalmtraffic,butwillfreeupadditionalspacewithinthestreetreservetowidenfootpaths,insertcyclelane/tracks,providebuslanes,streettreesandon-streetparking(allofwhichwillfurthercontributetotrafficcalming).


FIGURE 4.55: CARRIAGEWAY WIDTHS(note: Illustrations do not include cycle facilities)

Carriagewaywidthsforheavily-traffickedArterial and Link streetsinboulevardconfiguration.Maincarriagewaysuitableformoderatedesignspeeds.Includes access lanes with a lower design speed.

6-6.5m 6-6.5m6-6.5m 6-6.5m2.75-3m 2.75-3mStandardcarriagewaywidthsformulti lane Arterial and Link streets in boulevardconfiguration,includingbus lanes.

Standardlane/carriagewaywidthsformultilaneArterial and Link streets, includingbuslanes.Rangeforlowtomoderate design speeds.

5.5-6.5m3-3.25m 3-3.25m

CarriagewaywidthforLocal streetswithasharedsurfacecarriageway.

StandardcarriagewaywidthforLocal streets

CarriagewaywidthforArterial and Linkstreetsfrequentlyusedbylargervehicles.

6.5-7m 5-5.5m 4.8m

StandardcarriagewaywidthsforArterial and Link streets. Rangeforlowtomoderatedesign speeds.

5.5-6.5m


4.4.2 Carriageway Surfaces

Thematerial,textureandcolourofthecarriagewayareimportanttoolsforinformingdriversofdrivingconditions.Researchhasfoundthattheuseofrobustsurfacematerials (such as block paving) can reduce vehiclespeedsby4-7km/halone.31 The useofpaving,imprintedorloosermaterials(combinedwithnokerbing,seeSection4.4.8Kerbs)isoneoftheclearestwaysofreinforcingalow-speedenvironmentandofsignallingtoallusersthatathemaincarriagewayistobeshared(seeFigure4.56).Theuseofsuchsurfacesalsoaddsvaluetoplace,particularlyin historic settings.

Withregardofsurfacetypes:

• Theuseofstandardmaterials,suchasmacadam/asphaltshouldgenerallybeconfinedtostreetswithmoderatedesignspeeds(i.e.40-60km/h).

• Wherelowdesignspeeds(i.e.30km/h) are desirable changes in the colour or textureofthecarriagewayshouldbeusedperiodically,suchasatcrossingsoratstrategic locations, such as Focal Points.

• Wheresharedcarriagewaysareproposed(i.e.10-20km/h)changesincolourandtextureshouldbeappliedtothefulllengthofthestreet.

Theuseofrobustfinishesmayalsobeused,onallstreets,forthefullcarriagewaywherelargenumbersofpedestrianscongregate.Suchtreatments should be considered in Centres (i.e. along shopping streets), in all urban areas around Focal Points and adjacent to schools, squares, parks and other areas where vulnerable pedestrians are present (see Figure 4.57).

Designersshouldalsoconsidertheuseofat-gradematerialchanges(upto25mminheight)suchasatcrossings,particularlyonstreets with more moderate speeds and where the aim is not to require large reductions inspeedbuttoalertdriversofachangeindrivingconditionsahead(seeFigure4.58).

31 RefertoSection7.2.15oftheUKManual for Streets (2007).

Figure 4.58: Examples from Tallaght, Co. Dublin of a robust surface material (including a slight vertical deflection) designed to add value to place and increase pedestrian safety by alerting/slowing vehicles on approach to the crossing.

Figure 4.57: Example from Chapelizod, Co. Dublin, where the carriageway has been paved adjacent to a square in a village centre to add value to place and calm traffic in an area of higher pedestrian activity.

Figure 4.56: Example from Adamstown, Co. Dublin of a shared surface ‘homezone’ adjacent to a school. Paving materials, combined with embedded kerbs encourage a low speed shared environment.


Figure 4.59: Left turning slips (left) generally offer little benefit in terms of junction capacity and increase the number of crossings pedestrians must navigate. They also allow vehicles to take corners at higher speeds, exposing pedestrians and cyclists to greater danger. Where a large number of turning movements occur, left turning lanes (right) with tighter corner radii should be used.

4.4.3 Junction Design

Junctiondesignislargelydeterminedbyvolumesoftraffic.AsnotedinSection3.4.2TrafficCongestion,thedesignofjunctionshastraditionallyprioritisedmotorvehiclemovement.Designersmusttakeamorebalanced approach to junction design in ordertomeettheobjectivesofSmarter Travel (2009) and this Manual. In general designers should:

• Providecrossingsonallarmsofajunction.

• Reducekerbradii,therebyreducingcrossingdistancesforpedestriansandslowingturningvehicles(seeSection4.3.3Corner Radii).

• Omitleftturnslips,whichgenerallyprovidelittleextraeffectivevehicularcapacitybutarehighlydisruptiveforpedestriansandcyclists.Wheredemandwarrants,theymaybereplacedwithlefttuninglaneswithtightercornerradii(seeFigure4.59).

• Omitstaggeredcrossingsinfavourofdirect/single phase crossings (see Section 4.3.2PedestrianCrossings).

• Omit deceleration lanes. These are not required in low to moderate speed zones (i.e.upto60km/h).

• Includepedestrian,cyclistandbuspassengerdelaysintheoptimisationoftrafficsignalphasingandtimings.Thiswillalmostcertainlyleadtoareductionincycletimes.

• Minimisewaitingwithpedestraincycletimesofnomorethan90secondsatsignalisedjunctions(seeSection4.3.2PedestrianCrossings).

DesignersshouldalsohaveregardtoContext and Functionwhenselectingjunctiontypes(seeFigure4.60).Junctiondesignwillalsoneed to be considered in conjunction with crossingtypesandratioofflowtocapacities(seeSections4.3.2PedestrianCrossingsand3.4.2TrafficCongestion).


Traffic Signals

Thesecanprovideawiderangeofcapacitiesdependingonthewidthsoftheapproaches,thepresenceofbuslanesonapproach,cycletimesandturningtrafficflows.Trafficsignaljunctions can include pedestrian phases and advancedstoplinesforcyclists,thusmakingthemsafer.TrafficSignalsshouldgenerallybe used at all junctions between Arterial and Linkstreets.Wherepedestrianactivityisparticularlyhigh(suchaswithinaCentre or around a Focal Point),designersmayapplyall-roundpedestrianphasecrossingswithdiagonal crossings.

Roundabouts

Thesehaveawiderangeofcapacitiesdependingonthesizeandgeometryoftheroundabout, its approaches, and turning trafficflows,butaregenerallylowerthansignalised junctions. Large roundabouts are generallynotappropriateinurbanareas.Theyrequireagreaterlandtakeandaredifficultforpedestriansandcycliststonavigate,particularlywherecontrolledcrossings/cyclefacilitiesarenotprovided,andassuch,vehicleshavecontinuousrightofway.

Theuseoflargeroundabouts(i.e.thosewithradiigreaterthan7.5m)shouldberestrictedtoareaswithlowerlevelsofpedestrianactivity.Wherelargeroundaboutscurrentlyexist,roadauthoritiesareencouraged,aspartofanymajor upgrade works, to replace them with signalisedjunctionsorretrofitthemsothataremorecompactand/orpedestrianandcyclefriendly,asisappropriate.

Theuseofmorecompactroundabouts(i.e.thosewitharadiiof7.5morless)mayaddressmanyoftheissueshighlightedaboveandmayalsobeusefulasatraffic-calmingmeasure.Thesemaybeconsideredwherevehicleflowsarenotsufficienttowarrantfullsignalisation, such as on Links, and pedestrian activityismoremoderate,suchasinSuburbs and Neighbourhoods,providedtheyareappropriatelyfittedwiththeappropriatepedestrian crossings.

JUNCTION CONTROL

Figure 4.60: General junction selection based on the optimising pedestrian and cyclist movement whilst also balancing the needs of motor vehicle users.

StandardSignalisedJunctions.Areasofmoderatepedestrian/high-moderatevehicularactivity.

Signalisedjunctionwithall-roundpedestrianphasecrossing.Areasofhighpedestrianandvehicularactivity.

Miniorsharedroundaboutswithinformalcrossings.Areasoflowpedestrianactivity.

UncontrolledJunctions. Areasoflower/moderatepedestrianandvehicularactivity.

PriorityJunction. Areasoflower/moderatepedestrianandvehicularactivity.


Section4.8oftheNational Cycle Manual (2011)alsocontainsfurtherguidanceonthedesignanduseofroundaboutstomakethemmorepedestrianandcyclefriendly.Withregardtotheapplicationofthesemodels.

• Where compact roundabouts are proposed,designersmayapplytheMini or Shared roundabout models.

• Theuseoflargeroundabouts,suchasthe Segregated Track on Roundabout or Fully Segregated Roundabout, should be restricted to areas where pedestrian activityislow(asnotedabove).Theapplicationofthesemodelsmaybeacceptablewhereitisproposedtoretrofitan existing roundabout to make it more pedestrianandcyclefriendly.

Designersmayalsoconsidertheuseofsharedspace/informalroundaboutswithinlow speed environments, such as Centres. These junctions incorporate the design characteristicsofasharedspacejunction(i.e.nokerbs,pavedsurfacesetc)withcircularfeaturesplacedatthecentreandedges.Examplesofroundabouttypefeatures(sometimesreferredtoas‘roundels’)havebeensuccessfullyimplementedintheUKonheavilytraffickedjunctionswiththeeffectofenhancingplace,calmingtrafficandincreasingcyclist/pedestrianmobility(seeFigure4.61).

Priority Junctions (i.e. Stop and Yield junctions).

Thesegenerallyhavelowcapacityandareappropriateforlowtomediumflows.TheyshouldgenerallybeappliedwhereLocal streets meet Arterial or Link streets.

Uncontrolled Junctions

Thesegenerallyhavelowcapacityandrelyoninformalcommunicationbetweendrivers.Theyshouldgenerallybeusedwherevehicleflowsarelow,suchasthosebetweenLocalstreets.Designersmayalsoconsidertheuseofsharedspacejunctionsatbusierjunctions within low speed environments, such as Centres.Therearealsoexamplesofuncontrolled shared space junctions which caterforhigherflowswithoutsignalisation(seeFigure4.62andSection4.3.4PedestrianisedandSharedSurfaceStreets).

Figure 4.61: Examples from Ashford, UK (top) and Poynton, UK (bottom). The placement of a circular features with the shared space/traffic calmed environment creates an informal roundabout with fewer restrictions pedestrian/cyclist movement when compared to more conventional types (image sources: Hamilton-Baillie Associates and Ashford Borough Council).

34 35

relationship is stilted and awkward. It is unpredictable,

but when it works well it is very exciting indeed.

John Atkin began with research into the town’s

history and in the recent industrial past he found

a shape that became known as the DNA of the

scheme. This simple leather worker’s pattern was

cleverly translated into many forms including tree

grilles, bollards, seats and benches. But his tour-

de-force was the large not-a-roundabout feature, so

called because a roundabout is freighted with design

regulations that would have imposed black and

white chevrons and reflective stripes on his corten

steel centrepiece sculpture. Not-a-roundabout, the

tree grilles and the bollards have been installed, but

not all of his superb granite seats seem likely to be

commissioned due to pressure on scheme finances.

Nayan Kulkarni conducted a zonal study that

provided a rationale for the colour and intensity of

light at different locations along the route of the

ring road. He considered lighting the needs of the

pedestrian and vehicular activities along the route

and also thought about the possibility of using light

to help stitch the severed residential streets back to

the town centre. Nayan then designed a family of

bespoke lighting columns. These now march proudly

up Elwick Road and they bring a confident air of

design quality to Elwick Square, Ashford’s new major

public space.

Flume the linear floorscape sculpture by Simeon

Nelson, runs down Bank Street and east along

Elwick Road, making an artistic link between the

town centre and the International Station. It is an

elegant work that adds an intelligent presence to the

street scene.

Selecting the artistsThe artists RKL selected to join the IDT were John

Maine, John Atkin and Nayan Kulkarni. Simeon

Nelson had previously been engaged by Ashford

Borough Council to work with Whitelaw Turkington,

and his thinking for the linear floor piece ‘Flume’ was

already advanced.

As public art consultants we hold an extensive

database of artists’ work and over the years we have

had the pleasure of working with many good artists

on schemes large and small. A key consideration that

shaped our choices was the previous experience

of the artists, as we were well aware that the timing

of the design stages of the Ashford project would

put the artists under pressure to complete their

conceptual thinking and then their detailed design

work to a tight schedule.

Whilst our main thrust was to facilitate the integrated

artworks that would become a part of the new

landscape of Ashford we also wanted to introduce

a surprise element. To do this we created a brief

for an artist to devise a programme of challenging

temporary works on a transport theme. After

interview Michael Pinsky was selected and his

programme titled The Lost O took Ashford by storm.

John Maine has created significant works for

important sites across the UK, including Portland

Bill and the Southbank Centre. His work with the

IDT was on the northern section of the ring road, a

section that has now been re-scheduled for the future

delivery phases.

John Atkin’s work can be found on prominent sites

around the world. We thought his bold style, with

its strong individual forms, would work well with the

eco-sensibility of landscape architects Whitelaw

Turkington and the collaboration allowed John to

look at Elwick Road in its entirety and contribute his

thinking on the form of the hard landscape itself.

Nayan Kulkarni has worked on many architectural and

public realm projects and, in particular, we thought

his work with lighting technologies would raise the

game in Ashford. His considered street lighting colour

strategy, that differentiated between residential and

commercial areas and re-connected the town centre

with its previously severed neighbourhoods, and his

family of bespoke lighting columns have established

Ashford as a leader in this field.

Simeon Nelson is an artist with an interest in the

shared languages and underlying aesthetic concerns

that occur within different art forms. He also has a

passion for exploring how humans and nature interact,

and his work frequently involves collaborations with

structural engineers, biologists, dancers and others.

In his work he uses analogies and metaphors from

science, philosophy and theology, made manifest in

physical (often fractal) forms.

Michael Pinsky takes on the multiple roles of artist,

activist, planner and provocateur, and social space

as much as physical space provides the context for

his work. In response to a brief, which asked him

to mark the passing of the ring road, and to explore

issues of public space through sometimes playful

and subversive means, he conceived a multi-artist

temporary works programme that was delivered

during the middle of the construction period, which

resonates in Ashford to this day.

Inevitably Breaking Boundaries had both wins

and losses. Not every collaboration proved to be

a ‘marriage made in heaven’, yet some thrived

wonderfully well and are still thriving and developing

in other projects, in Ashford and elsewhere. This

is invariably the way with integrated design team

working. Some relationships spark the creative

process and produce much more than the sum

of the parts. Others never quite get there and the

Figure 4.62: Example from Coventry, UK of a shared surface uncontrolled junction. The level of traffic using the junction would normally warrant some form of control, however, its traffic calmed nature allows for drivers to communicate with each other and pedestrians to establish movement priorities (image source: Hamilton-Baillie Associates).


4.4.4 Forward Visibility

ForwardVisibility,alsoreferredtoasForwardSightDistance(FSD),isthedistancealongthestreetaheadwhichadriverofavehiclecansee.TheresultsofresearchcarriedoutbyTransportResearchLaboratoryUK(TRL)forthe UK Manual for Streets(2007)foundthatreducingforwardvisibilityisoneofthemosteffectivemeasuresusedtoincreasedrivercaution and to reduce speeds.32

Theminimumlevelofforwardvisibilityrequiredalongastreetforadrivertostopsafely,shouldan object enter its path, is based on the StoppingSightDistances(SSD).TheSSDhas3constituent parts:

• PerceptionDistance:Thedistancetravelledbeforethedriverperceivesahazard.

• ReactionDistance:Thedistancetravelledfollowingtheperceptionofahazarduntilthe driver applies the brakes.

• BrakingDistance:Thedistancetravelleduntil the vehicle decelerates to a halt.

The perception and reaction distances are generallytakenasasingleparameterbasedon a combined perception and reaction time. TheformulaforthecalculationofSSDis:

SSD=vt+v2/2d

32 RefertoSection7.4.4ofUKManual for Streets (2007) and UK Manual for Streets: Redefining Residential Street Design(2006).

Design Speed (km/h)

SSD Standard (metres)

10 820 1530 2440 3650 4960 65

Forward Visibility on Bus Routes

Design Speed (km/h)

SSD Standard (metres)

10 720 1430 2340 3350 4560 59

Forward Visibility

SSD STANDARDS

Table 4.2: Reduced SSD standards for application within cities towns and villages. Reduced forward visibility increases driver caution and reduces vehicle speeds.

Where:

v=vehiclespeed(m/s)t=driverperception-reactiontime(s)

d=decelerationrate(m/s2)

SSDshavegenerallybeenappliedaccordingtothosecontainedwithintheNRADMRBTD9whichwherederivedfromtheUKDMRBManualofthesamenameusingaperceptionreactiontimeof2seconds,andadecelerationrateof0.25g,or2.45m/s2.TRLfoundtheseSSDvaluestobeoverlyconservativeastheyunderestimateddriverreaction times, deceleration rates and did not take into account actual road design details.33Basedonthisresearch,adriverperception-reactiontimeof1.5seconds,andadecelerationrateof0.45g,or4.41m/s2, should beappliedwithdesignspeedsof60km/handbelow.ForlargervehiclessuchasHGVsandbuses,adecelerationrateof0.375g,or3.68m/s2 should be applied.

ArevisedsetofreducedSSDs,basedontheparameters included in the UK Manual for Streets (2007), are presented in Table 4.2. The reducedSSDsshouldbeappliedaccordingto the designspeedofastreet(seeSection4.1.1 A Balanced Approach to Speed) at junctionsandalongthealignmentofastreet(seeSections4.4.5VisibilitySplaysand4.4.6AlignmentandCurvature,respectivelyandAdvice Note 3 - Geometric Standards.

33 RefertoManual for Streets: Evidence and Research (TRL Report 661) (2007).


4.4.5 Visibility Splays

Visibilitysplaysareincludedatjunctionstoprovide sight lines along the intersected street toensurethatdrivershavesufficientreactiontimeshouldavehicleentertheirpath.Visibilitysplaysareappliedtopriorityjunctionswheredrivers must use their own judgement as to whenitissafetoenterthejunction.Junctionvisibilitysplaysarecomposedoftwoelements;the X distance and the Y distance.

• The X distance is the distance along theminorarmfromwhichvisibilityismeasured.Itisnormallymeasuredfromthecontinuationofthelineofthenearsideedgeofthemajorarm,includingallhardstrips or shoulders.

• The Y distance is the distance a driver exitingfromtheminorroadcanseetotheleftandrightalongthemajorarm.Itisnormallymeasuredfromthenearsidekerboredgeofroadwaywherenokerbisprovided.

TheprocedureforcheckingvisibilitysplaysatjunctionsisillustratedinFigure4.63.Anadditionalcheckismadebydrawinganadditional sight line tangential to the kerb, oredgeofroadway,toensurethatanapproaching vehicle is visible over the entire Y distance.

1: VISIBILITY SPLAY (no constraint on overtaking)2: ALTERNATIVE VISIBILITY SPLAY (constraint on overtaking)

Figure 4.63: Forward visibility splays refer to an X and Y value. The X value allows drivers to observe traffic on the intersected arm. The Y value allows the driver of a vehicle to stop safely should an object enter its path, and is based on the SSD value.

Longer X distances allow drivers more time toobservetrafficontheintersectedarmandtoidentifygapsmorereadily,possiblybeforethevehiclecomestoastop,thusallowing increased vehicle speeds through junctions. Furthermore, a longer X distance mayencouragemorethanonevehicleonthe minor arm to accept the same gap even whereitisnotidealthattheydoso.Neithercircumstance is desirable in urban areas. Theattentionofadrivershouldnotsolelybefocusedonapproachingvehiclesandtheacceptanceofgaps.Thepedestrian/vulnerable road users should be higher in the movementhierarchy

Forthisreason,priorityjunctionsinurbanareasshould be designed as Stop junctions, and a maximumXdistanceof2.4metresshouldbeused.Indifficultcircumstancesthismaybereduced to 2.0 metres where vehicle speeds areslowandflowsontheminorarmarelow.However,theuseofa2.0metreXdistancemayresultinsomevehiclesslightlyprotrudingbeyondthemajorcarriagewayedge,andmayresultindriverstendingtonoseoutcautiouslyintotraffic.Careshouldbetakentoensurethatcyclistsanddriverscanobservethisoverhangfromareasonabledistanceandmanoeuvretoavoiditwithoutunduedifficulty.

12

1

Y distanceX distance

Constraint on overtaking?

Y distance

12

1


X distance

Y distanceX distance

1

12



TheYdistancealongthevisibilitysplayshouldcorrespondtotheSSDforthedesignspeedofthemajorarm,takenfromTable4.2whilealsomakingadjustmentsforthosestreetswhicharefrequentedbylargervehicles.Forexample,within Industrial Estates and/or on Arterial and Linkstreetswithhigherfrequencybusroutes.

Ingeneral,junctionvisibilitysplaysshouldbekeptclearofobstructions,however,objectsthatwouldnotbelargeenoughtowhollyobscureavehicle,pedestrianorcyclistmaybe acceptable providing their impact on the overallvisibilityenvelopeisnotsignificant.

Slim objects such as signs, public lighting columnsandstreettreesmaybeprovided,butdesignersshouldbeawareoftheircumulative impact.

• Streetfurniture,suchasseatsandbicyclestandsmayalsobeacceptable,subjecttobeingsufficientlyspaced.

• Splaysshouldgenerallybekeptfreeofon-streetparking,butflexibilitycanbeshown on lower speed streets with regard to minor encroachments.

• Pedestrianguardrailscancausesevereobstructionofvisibilityenvelopes,andtheuseofguardrailsshouldbeavoided(seeSection4.2.5StreetFurniture).

Designersshouldalsocheckthevisibilityenvelop in the vertical plane on approach tojunctions(seeSection4.4.6AlignmentandCurvature,Figure4.67)

Designersmayhaveconcernsaboutreducingvisibilitysplaysatjunctionsthatcarryhighervolumesoftrafficatmoremoderatespeeds.ThisissuewasaddressedfurtherinrespectofresearchcarriedfortheUKManual for Streets 2 (2010).Thisincluded‘busyradialroads’,manyofwhichincludedbusrouteswithinavarietyof20,30and40mphenvironments.34 The research concluded that there is no evidence thatreducedSSDsaredirectlyassociatedwith increased collision risk, as shown on a varietyofstreettypesatavarietyofspeeds.The Manual for Streets 2 (2010)alsoreferstoresearchwhereitwasfoundthathighercyclecollisionratesoccurredatT-Junctionswithgreatervisibility.35 The research concluded that this was because drivers were less cautiouswheregreatervisibilitywasprovided.

Designersmustalsotakeaholisticviewoftheapplicationofreducedforwardvisibilitysplays.As illustrated in the Adamstown Street Design Guide (2010), there are other place making andtrafficcalmingbenefitsthatcanbeimplementedbyreducingforwardvisibilitysplaysatjunctions(seeFigure4.64).

34 Referto10.4ofUK Manual for Streets 2 (2010) and the report High Risk Collision Sites and Y Distance Visibility (2010).

35 Referto Layout and Design Factors Affecting Cycle Safety at T-Junctions (1992).

Figure 4.64: Flow diagram showing the interlinked traffic calming and place making benefits of reduced visibility splays.

INCREASED RETAIL VIABILITY

INCREASED ON-STREET PARKING

INCREASED PEDESTRIAN ACTIVITY

REDUCED BUILDING SETBACKS

REDUCED VISIBILITY SPLAYS

INCREASED LEVELS OF

TRAFFIC CALMING


4.4.6 Alignment and Curvature

Changesinthealignmentofroadsandstreetsaregenerallyreferredtointhehorizontalandvertical sense. When these changes occur, theFSD,isreducedand,asnotedabove,thisisoneofthemosteffectivemeasuresusedtoincreasedrivercautionandcalmtraffic(seeFigure4.65).

Horizontal Alignment

Thehorizontalalignmentofastreetconsistsofstraight sections and curves. Whilst changes tothehorizontalalignmentcalmstraffic,thisneedstobebalancedwithsafetyconcerns.To prevent abrupt changes in direction minimumFSDrequiredalongastreetshouldcorrespondtotheminimumSSDappropriatetothedesignspeed.FSDischeckedathorizontalcurvesbymeasuringbetweenpointsonthecurvealongthecentrelineoftheinnerlane(seeFigure4.66).

Frequent changes to the horizontal alignment shouldalsobebalancedwithpermeabilityandlegibility.Overuseofchangesinthedirectionofstreetsmaydisorientatepedestrians and increase walking distances between destinations. In this regard:

• DesignersshouldavoidmajorchangesinthealignmentofArterial and Link streets astheserouteswillgenerallyneedtobedirectionalinordertoefficientlylinkdestinations.

• MajorchangesinhorizontalalignmentofArterial and Link streets should be restricted to where required in response to the topographyorconstraintsofasite.

• There is greater scope to use changes in horizontal alignment on Local streets to promote lower speeds and a more intimatesenseofplace(seeSection4.4.7HorizontalandVerticalDeflections)

• Designersshouldnotrelyoncurvaturealone to reduce vehicle speeds. Changes in horizontal alignment should be combined with contextual measures that reduceforwardvisibility,suchasbuildinglinesandon-streetparking.

EnvelopeofVisibility

Figure 4.66: Forward visibility at horizontal curves need to take account of SSD values

Figure 4.65: Example from Clongriffin, Co. Dublin where a change in the alignment of the street calms traffic as drivers proceed cautiously due to the uncertainly of what lay ahead (image source: Google Street View).

StoppingSightDistance


Horizontal Curvature

Atahorizontalcurve,thecentrifugalforcea vehicle travelling around that curve is generallycounteractedbyacombinationof2factors:frictionbetweenthetyresandtheroadsurface,andsuperelevationofthecarriageway,wherethecarriagewayis constructed such that the outside carriagewayedgeishigherthantheinsidecarriagewayedge.Traditionally,thedesignapproach has been to combine these factorstoensurethatavehiclecantravelaround a bend without reducing speed or withoutcausingsignificantdiscomforttotheoccupantsofthevehicle.Whereahorizontalalignment along a street requires changes in direction, the curves between straight sections should have radii in accordance with Table 4.3.

Crossfall

Designersshouldalsoconsidersuperelevationwhereonesideoftheroadisdesignedtobe higher than the other in order to resist thecentrifugaleffectofturningacorner.Astheaimofsuperelevationistoassistdriversto maintain higher speeds around curves, its use is inappropriate where the design is intended to achieve a moderate or low speed environment. As also noted in the Manual for Streets 2 (2010),superelevationisalsodifficulttoimplementinurbanareaswithfrequentjunctionsandpointsofaccess.36

36 RefertoSection8.3oftheUK Manual for Streets 2 (2010).

Howeveracrossfallof2.5%isgenerallyprovidedoncarriagewaystoassistindrainage, which would tend to result in adverse camber at horizontal curves. Consequently,inordertoassistinachievinglower vehicle speeds through a more restrictive horizontal alignment, there is a need to provide sharper horizontal curves thatdonothavethebenefitofhighlevelsofsuperelevationtocounteractthecentrifugalforce.DesignersshouldrefertoTable4.3forminimumradiuswithadversecamberof2.5%.

Wheretheintroductionofradiilessthanthoseforminimumradiuswithadversecamberof2.5%isunavoidable,areasonablelevelofsuperelevationmaybeintroducedtoeliminate adverse camber and introduce afavourablecrossfall.Minimumcurveradiiforasuperelevationrateof2.5%arealsopresentedinTable4.3,andmaybeusedinsuch circumstances.

Design Speed (km/h) 10 20 30 40 50 60Crest Curve K Value N/A N/A N/A 2.6 4.7 8.2

Sag Curve K Value N/A N/A 2.3 4.1 6.4 9.2

Table 4.3: Carriageway geometry parameters for horizontal and vertical curvature.

Design Speed (km/h) 10 20 30 40 50 60Minimum Radius with adversecamberof2.5%

- 11 26 56 104 178

Minimum Radius with superelevationof2.5%

- - - 46 82 136

VERTICAL CURVATURE

HORIZONTAL CURVATURE


Vertical Alignment

Averticalalignmentconsistsofaseriesofstraight-linegradientsthatareconnectedbycurves,usuallyparaboliccurves.Verticalalignmentislessofanissueonurbanstreetsthatcarrytrafficatmoderatedesignspeedsand changes in vertical alignment should be considered at the network level as a response tothetopographyofasite.

TherequiredenvelopeofforwardvisibilityintheverticalplaneisillustratedinFigure4.67below. The envelope should encompass theareabetweenadrivereyeheightintherangeof1.05metresto2.00metres,andanobjectheightintherangeof0.6metresto2.00metres

Vertical Curvature

Where changes in gradient are required along an alignment, vertical curves are introduced, suchthattheappropriateSSDsareachieved,andanadequatelevelofdrivercomfortisprovided.Ordinarilyinurbanareaswhereit can be expected that vehicle speeds will reduce in response to changes in alignment, it willbesufficienttodesignverticalcurvessuchthattheminimumSSDisprovided.

VerticalcurvescantaketheformofCrestorSagcurves,thelengthofaverticalcurve,L, is the critical design parameter, and is determinedbymultiplyingtheKValuessetoutinTable4.3bythealgebraicchangeofgradient expressed as a percentage, that is:

L=Ka

Where:

K=Theconstantofcurvature a=Thealgebraicchangeingradient.

Vertical Crest Curve Design

Atcrestcurvesvisibilitycanbeobstructedbytheroadsurfaceitself.Crestcurve,accordingly,shouldbedesignedsuchthatthecurvatureissufficienttomaintainanadequateFSDandSSDforadriver.Inurbanareas,wherevehicle speeds are low and gradients are generallymodest,thedesignofverticalcrestcurvescanbesimplifiedasfollows:

• Forverylowdesignspeeds(i.e.lessthan40km/h),andwherethealgebraicdifferencein gradient between straight sections is less than12%,itwillgenerallynotbenecessarytospecificallydesignaverticalcrestcurve;howeverthecarriagewayshouldbe shaped to avoid an abrupt change in vertical alignment.

• Fordesignspeedsof40km/handabove,

andagainwherethealgebraicdifferenceingradientismodest,uptoamaximumof12%,itwillnormallybesufficienttoprovidea vertical curve with a length determined usingtheK-valuespresentedinTable4.3.

In exceptional circumstances where the algebraicdifferenceingradientexceedstheselimits,itwillbenecessaryforthedesignertodetermineacrestcurvelengthsuitableforthecircumstancesfromfirstprinciples.

Figure 4.67: Visibility envelope in vertical plane.

EnvelopeofVisibility

StoppingSightDistance

2m

0.6m 1.05m 2m

DirectionofTravel


Vertical Sag Curve Design

When designing vertical sag curves, there are three potential design parameters that need to be considered:

• DriverComfort.• ClearancefromStructures.• Night-timeConditions.

Inurbanareas,theobstructionofvisibilitydueto structures (overbridges, gantries etc.) is likelytobeanuncommonoccurrence,andnighttimevisibilityonlybecomesanissueonunlitroads.ThereforethesagcurveKvaluespresentedinTable4.3arebasedonthedrivercomfortparameter,andhavebeenderivedusingacomfortcriterionof0.3m/s2maximumvertical acceleration.

Maximum and Minimum Gradients

Inurbanareas,itislikelythatthecomfortofvulnerable road users will be the determining factorfordesirablemaximumlongitudinalgradientsonstreets.PartMofthebuildingregulations advises that access routes with a gradientof1:20orlessarepreferred.Thereforeamaximumgradientof5%isdesirableonstreets where pedestrians are active.

Inhillyterrain,steepergradientsmayberequired but regard must be had to the maximum gradient that most wheelchair users cannegotiateof8.3%,althoughthisshouldbe limited to shorter distances A designer mayneedtoconsidermitigationmeasures,such as intermediate landings, to ensure that pedestrian routes are accessible. This also needs to be considered at the network level and as a response to place making.

Theinclusionofstreetsthatexceedthesegradientsmaynotbesignificantwithinanetwork where there are alternative routes that can be taken between destinations and wheresteepergradientsmayinfacthaveplacemakingbenefits.

Aminimumlongitudinalgradientof0.5%isdesirabletomaintaineffectivedrainageonstreets. Care needs to be taken at vertical curves, and in particular at sag curves, to ensurethatthereisprovisionatlevelpointsofcurvestoallowsurfacewatertorunoffthecarriageway.


Figure 4.69: Example from Dorset Street, Dublin, where the carriageway has been raised and paved to slow turning vehicles and enhance the pedestrian crossing.

Figure 4.68: illustration of how off-setting junctions can create a change in alignment (without reducing permeability or legibility) and reduce forward visibility.

4.4.7 Horizontal and Vertical Deflections

Horizontalorverticaldeflectionsarechangesthatoccurwithinthealignmentofthecarriagewaytoslowvehiclesbyrequiringdrivers to slow and navigate obstacles. Deflectionsincludechicanes(horizontal)orramps(vertical).Theuseofsuchphysicallyintrusivemeasuresisnotnecessarywithinaself-regulatingstreetenvironment.Lessaggressivefeatures,suchasjunctionoffsets(seeFigure4.68),raisedtablesandchangestokerblines,canbeusedstrategicallyassupplementarymeasureswhichcalmtrafficandassistpedestrianmovementbyallowingthemtocrossatgrade(seeSection4.3.2PedestrianCrossings).

Raisedtables,orplatforms,maybeplacedstrategicallythroughoutanetworktopromotelower design speeds, slow turning vehicles at junctions and enable pedestrians to cross the streetatgrade.Keylocationswheretheseshould be considered include:

• On longer straights where there is more than 70m between junctions.37

• Atequalpriorityjunctions.

• At entrance treatments where Local streets meet Arterial and Link streets (see Figure4.69).

• Outside Focal Pointsandareasofcivicimportance (such as schools).

37 RefertoSection7.4.3oftheUKManual for Street (2007).

• At pedestrian crossings.

• Toreinforceachangebetweendesignspeeds (such as at entrance treatments).

Asraisedtablesareprimarilydesignedtoreinforcelowerspeedenvironments,theiruseshouldgenerallybelimitedtoLocal streets and/or the Centres.TheuseofraisedtablesmorebroadlyacrossArterial and Link streets (excluding those within Centres) should be limited to sections where speeds are to be loweredforaparticularpurpose(i.e.adjacentto Focal Points and/orkeypedestriancrossings).

Theprincipalaimofthedesignershouldbe to slow vehicles without causing undue discomfort.Inthisregard:

• Anentryslopeof1:20willallowmostvehicles to cross at moderate speeds

• Anentryslopeof1:15ismoreappropriateforlowerspeeds.

• Theminimumlengthoflevelsectionofthetable should be 2m (to allow a pedestrians to cross).

• Theheightofaraisedtableshouldgenerallycorrespondwiththatoftheadjoining kerb. Where buses operate themaximumheightshouldbe75mmtoreducepassengerdiscomfort.


Horizontaldeflectionsareparticularlyeffectivewhen considered at the network level and used in combination with restrictions in forwardvisibility(seeSection4.4.6Alignmentand Curvature and Figure 4.70). When deployedthroughoutanetworkonLocal streetstheycanalsobeusedtodiscouragethroughtraffic(seeSection3.4.1VehiclePermeability).Deflectionscanbecreatedbyvaryingthekerbline/streetalignmentcausingthecarriagewaytobroadenandnarrowand/orcreatingaseriesofdirectionaladjustments.Carparkingmayalsobeusedtosimilareffect(seeSection4.4.9On-StreetParkingandLoading).Othermethodsthatmaybeconsideredatthenetworklevelincludeoff-settingjunctionstocreatea3WayOffSetNetwork(SeeSection3.4.1VehiclePermeability).

Singulartreatmentsincludepinch-pointsthatnarrowthewidthofthecarriagewayoverashortsectionofthestreet.Thesecanbeused in combination with raised tables at keylocationsonLocal streets and/or within the Centres (seeFigure4.71).Tobevisuallyeffectiveapinchpointshouldseektoreducethewidthofthecarriagewaybyaminimumof0.5mforaminimumlengthof6m.38

38 Aminimumof3.7m(3.1mat‘gateways’)isrequiredforfirevehicleaccessasperTable5.2ofthe Building Regulations 2006(TechnicalGuidanceDocumentB–FireSafety).

Figure 4.70: Examples from Poundbury, Dorchester, UK, where changes in the kerb line and carriageway alignment calm traffic by limiting forward visibility, creating pinch points and requiring multiple changes in direction.

Figure 4.71: An example from Ingress Park, Kent, UK, of how the path and speed of a vehicle is altered within a low speed environment through the use of vertical and horizontal deflections (and material changes).


4.4.8 Kerbs

Kerbstraditionallyprovidedastreetdrainagefunctionbuthavemorerecentlycometodefinethepedestriandomainfromthevehicularcarriageway.Insodoingkerbsarekeytoestablishingthelevelofsegregationor integration which is to occur within a street.Lowerkerbs,orlackthereof,canthereforecreateagreatersenseofsharedspaceandcanbeusedtocalmtraffic.Lowerkerbheightsarealsoeasierforpedestrianstonegotiate,particularlyforthemobilityimpaired.

Withregardtotheheightofkerbs:

• Thestandardheightforkerbsis125mmandthisprovidesacleardefinitionofasegregated street environment. These should be used on all streets where design speedsandpedestrianactivityaremoremoderate, such as on Arterial and Link streets.

• Lowerkerbsof60mmaremoreappropriateinareasofhigherpedestrianactivityandwherelowerdesignspeedsare applied, such as on all streets within Centres, around Focal Points and on Local streets(seeFigures4.72and4.73).

• Whereasharedsurfaceisproposedakerbshouldnotbeused.Designersmayconsiderembeddingakerblineordrainage channel (see Figure 4.74) into thecarriagewaytoindicateanareaofpedestrianrefuge.Thisisparticularlyimportantforvisually-impaireduserswhofeellesscomfortableonsharedsurfacesandalsorequireakerblinefornavigation(seeSection4.3.4PedestrianisedandShared Streets).

Changes to kerb lines can also be used to slowdriversatcriticalpointsbychangingthealignmentofthecarriagewaytocreatepinch-points,build-outsandhorizontaldeflections(see Section 4.4.7 Horizontal and Vertical Deflections).Build-outsshouldbeusedonapproaches to junctions and pedestrian crossings in order to tighten corner radii, reinforcevisibilitysplaysandreducecrossingdistances(seeSections4.3.2PedestrianCrossingsand4.4.5VisibilitySplays).

Figure 4.73: Example from Clongriffin Co. Dublin, where the footpath, kerb line and vehicular carriageway are at the same level. Whilst pedestrian and vehicular space are still clearly defined, a greater sense of shared space is still created.

Figure 4.74: Example of an drainage channel on Exhibition Road, London. The kerb line indicates an area of pedestrian refuge and is used to guide the visually impaired.

Figure 4.72: Example of a low kerb from Drogheda, Co. Louth, which is used to reinforce lower design speeds and create a greater sense of shared space.


4.4.9 On-Street Parking and Loading

OneoftheprincipalobjectivesofthisManualistopromotetheuseofmoresustainableformsoftransport.Whilstaplace-basedapproach to street design will reduce car dependency,asnotedintheUrbanDesignManual,39peoplemaywishtoownandparkacar,evenifitisnotusedonaregularbasis.On-streetparkingandloadingreferstospacesthataredirectlyadjacenttoandaccessiblefromthemainvehicularcarriageway.On-street parking, when well designed can:

• Calmtrafficbyincreasingdrivercaution,visuallynarrowthecarriagewayandreduceforwardvisibility.

• Addtothevitalityofcommunitiesbysupporting retail/commercial activities that frontontostreetsthroughthegenerationofpedestrianactivityaspeoplecomeandgofromtheirvehicles.

• Contributetopedestrian/cyclistcomfortbyprovidingabufferbetweenthevehicularcarriagewayandfoot/cyclepath.

• Reducetheneedortemptationfordriverstokerbmountandblockfoot/cyclepaths.

• Providegoodlevelsofpassivesecurityasspacesareoverlookedbybuildings.

Thequantityofon-streetparkingthatisneeded in a given area depends on a numberoffactors,butismostcloselyrelatedtoproximitytoCentres,theavailabilityofpublictransportandthedensity,typeandintensityoflanduse.Notwithstandingthesefactors,on-streetparkinghasafinitecapacity,dependingontheperunitparkingrequirements. For example in residential areas:

• On-streetparkingalonecangenerallycaterfordensitiesupto35-40dwellingsperha (net).

• Oncedensitiesreach40-50dwellingsperha (net) the street will become saturated with parking and reduced parking rates(amaxof1.5perdwelling)and/orsupplementaryoff-streetparkingwillberequired.

39 RefertoSection11oftheUrban Design Manual (2010).

• Fordensitiesover50dwellingperhectare,largeareasofoff-streetparking,suchasbasements,willgenerallyberequired.

Gettingthebalancerightpresentsachallengetodesigners.Ifparkingisoverprovideditwillconflictwithsustainabilityobjectivesandcanbevisuallydominant.Conversely,ifparkingdoesnotcaterforuserneedsorisunderprovideditmayencouragepoor parking practices (including illegal ones) suchaskerbmounting,parkingonfootpathsandwithinareasofopenspace.

Whilstoff-streetparkingmayformpartofadesignresponse,thefirstpriorityofadesignershouldbetolocateparkingon-streetasfollows:

• On Arterial and Linkstreetson-streetparking spaces should be provided in aseriesofbaysthatareparalleltothevehicularcarriageway.

• Perpendicularorangledspacesmaybeprovided in lower speed environments such as Localstreets.TheymaybeappliedmoregenerallyinCentrestocaterforincreased demands around shopping areas.

• On-streetparkingonpublicstreetsshouldnot be allocated to individual dwellings. Thisallowsforamoreefficientturnoverofspacesand,assuch,fewerspacesareneeded overall.

• Loadingfacilitiesshouldpreferably,beprovidedoffstreet.However,thisisnotalwayspossibleordesirablewithinoldercentres and/or where it would lead to anexcessivenumberofaccesspointstodriveways.

Thereareanumberofmeasuresthatshouldbeusedbydesignerstoensurethatparkingand loading areas are well designed (see Figures4.75and4.76):

• Toreducethevisualimpactofparkingthenumberofparkingspacesperbayshouldgenerallybelimitedtothreeparallelspaces (including loading areas) and six perpendicular spaces.


• Perpendicularparkingshouldgenerallyberestrictedtoonesideofthestreettoencourageagreatersenseofenclosureand ensure that parking does not dominate the streetscape.

• Toreinforcenarrowercarriageways(particularlywhenspacesareempty)eachparking/loadingbayshouldbefinishedsothatitisclearlydistinguishablefromthemaincarriageway.

• Kerbbuild-outs,orsimilartreatment,shouldbeprovidedtoseparateeachbankofparking/loading. These will enable space fortheplantingofstreettreesandotherstreetfacilities(suchaslightingorbikeracks).40

• Kerbbuild-outsshouldalsobeprovidedontheapproachtojunctionstofacilitatevisibilitysplays(seeSection4.4.5-VisibilitySplays),reducecornerradii(seeSection4.3.3CornerRadii)andensureaclearlineofsightbetweenvehiclesandpedestriancrossings.

40 Refertopage186oftheNational Cycle Manual (2011).

1-2m

2m2.

4m5.5m

4.8-5m

1-2m

2m

Figure 4.76: Extract from the Newcastle LAP (South Dublin County Council) illustrating the layout of a Local street with a uniform mix of parallel and perpendicular parking.

Figure 4.75. Example from Ballymun, Co. Dublin (top) and Leixlip, Co. Kildare (bottom) where kerb build-outs and contrasting materials are used to separate and define bays of parking from the vehicular carriageway, reduce corner radii and facilitate planting or landscape treatments.


• Whereon-streetparkingisprovidedadjacenttocyclepaths/lanesavergeshould be provided to allow additional spaceforopeningdoors(seeSection4.3.5CycleFacilities).

Parkingmaybeaddedtoexistingstreetswherethecarriagewayisexcessivelywideasameansofnarrowingit(seeFigure4.77). However, as noted in Section 4.4.1 CarriagewayWidths,thefirstpriorityofdesignersshouldbetoimprovefacilitiesforpedestrianandcyclists,priortotheadditionofon-streetparking.

Arangeoflessformaloralternativeparkingarrangementsmaybeusedwheredesignspeedsarelower,particularlyonLocal streets and within Centres. A diverse range ofparkingtypesmaybeprovidedtocreatemore intimate spaces, reduce the amount oflinemarking/constructedelementsand/orreinforcethelowspeedenvironment.Suchmeasuresmayincludethefollowing:

• Horizontaldeflectionsmaybeproducedbyswitchingthelocationofparkingbaysfromonesideofthestreettotheother,orfromthesideofthestreettothecentre(seeFigure4.78).

Figure 4.78: Illustration of informal on-street parking distributed to form a series of horizontal deflections and pinch points to reinforce a low speed environment.

Figure 4.77: Example from Fettercairn, Co. Dublin where a ‘distributor’ style road was narrowed by adding bays of parallel parking as part of a package of works aimed at calming traffic and improving the sense of place.


• Parkingbaysmaybelessformallydefinedforexample,thepresenceofthestreettreeembeddedintothecarriagewaywillalso indicate where to park (see Figure 4.79).

• On-streetandin-curtilagespacesmaybeintegrated to reduce the overall amount ofparkingthatison-streetandcreatea‘mews’likeenvironment(seeFigure4.79.)

• Placingparkingwithinthecentralareaofastreettoprovideagreaterlevelofsurveillance.

• Loadingareasmaybeprovidedatgradewithfootpathareas(i.e.withinaverge),sothatwhennotinusetheyrevertbacktopedestrianuse(seeFigure4.80).

Inareasofhighdemand,parkingmaybeprovidedwithinthecentralareasofstreetaswellastheedgeofthecarriagewaytocreateanon-streetparkingcourtyard(seeFigure4.81).Suchspacesshouldbelimitedinsize, well planted and landscaped to ensure thatthecourtyardisnotoverlydominatedbyparked vehicles.

DesignersmayalsorefertotheUrban Design Manual (2010)41 and UK Parking: What Works Where (2006),forfurtherguidance. With regardtothedesignofindividualparking/loading spaces42:

• Thestandardwidthofaspaceshouldbe2.4m.

41 RefertoChapter11ofthe Urban Design Manual (2010).

42 SeealsoSection1.4.2ofBuilding for Everyone: A Universal Design Approach for Accessible Parking Spaces.

Figure 4.79. Example from New Hall, UK where a variety of in-curtilage and on-street parking is provided. On-street parking is provided semi-informally (indicated by the planting of trees). The parking of vehicles further calms traffic by providing a series of horizontal deflections.

Figure 4.80: Example from Walworth Road, London, UK, where a loading bay, provided within a verge, can revert to pedestrian space when not used.


• Thestandardlengthofaspaceshouldbe6m(parallelspaces).

• Thestandarddepthofaperpendicularspaceshouldbe4.8m(notincludingaminimum0.3moverhang,seeSection4.3.1Footways,VergesandStrips).

• Thedepthofangularparkingshouldbe4.2mfor60o angleparkingand3.6mfor45o angle parking.

• Thedimensionsofaloadingbayshouldbe2.8x6mtocaterforlargevans.Facilitiesforlargervehicles,suchastrucks,shouldbelocatedoff-street.

There are additional design considerations associated with perpendicular or angled spacestoensurethattheydonotresultinexcessivelywidevehicularcarriageways.Perpendicularspacesgenerallyrequireaminimumcarriagewaywidthof6m,whichisgenerallytoowideforLocal streets. Where additionalspaceisneeded,manoeuvrabilityshouldbeprovidedwithintheparkingbayitselfandkerbbuild-outsshouldextendforwardofeachbankofparkingtonarrowthecarriageway.Alternatively,additionalmanoeuvrabilitycanbeprovidedbydesigningwiderspaces.Forexample,ifthewidthofparkingspacesis2.6m,thecarriagewaymaybereducedto5m(seeFigure4.82).

Figure 4.81: Examples from Belmayne (top) and Ballycullen (bottom), Co. Dublin of a well landscaped parking court integrated within a street environment .

5.5m 4.8-5m0.5m 0.3m

Figure 4.82: Example of how additional manoeuvrability may be provided for vehicles in areas of perpendicular parking whilst minimising carriageway widths. The images to the left are extracted from the Manual for Streets (2007) and illustrate the provision of wider spaces. The image to the right also shows the use of small verges.

CHAPTER 5: IMPLEMENTATION

The interlinked nature of street design requires designers to take a strategic plan-led approach that embraces a range of skills and perspectives from design professionals and the broader community.


5.0 IMPLEMENTATION

5.1 The Challenge Ahead

ThisManualoffersdesignerstherationaleandthetoolstoenactthechangerequiredbybroader government policies. Implementing suchchangeishighlychallenging.Ashighlightedbythenumerousexemplardesignscontained within this Manual, such change is achievable(seeFigure5.1).

Theimplementationofintegrateddesignsolutions to urban road and street design requires a strategic approach where design professionals,electedmembersandthebroadercommunityworkcollaboratively.

Such integrated solutions should be supported by:

• Aplan-ledapproachtodesignfordevelopmentofallsizes,andinclusiveofthoseundertakenbythepublicorprivatesectors.

• Greatercollaborationfromavarietyofdesignprofessionsandmorein-depthconsultation with/between road authorities andthebroadercommunity.

Aplan-ledandmulti-disciplinaryapproachisdiscussed in the ensuing sections.

Figure 5.1: Images of Dorset Street, Dublin (part of the N1 national route), demonstrate how better outcomes can be achieved by shifting away from convention and embracing a more inclusive and strategic approach to design.

BEFORE

AFTER


5.2 A Plan-Led Approach

5.2.1 Policy and Plans

Spatialplansareakeyelementintheimplementationofmoreintegratedstreetdesign.Theyshouldincludeinformationon how the principles, approaches and standards within this Manual can be applied to promote sustainable cities, towns and villages. In particular when preparing policies and objectives on transportation and the promotionofmoresustainablemodesoftransport, regard must be had to the detailed technical advice and guidance in this Manual.

Thehierarchyofspatialplansisasfollows;

1. DevelopmentPlans2. LocalAreaPlans3. Masterplans*4. Movement Frameworks*5. PublicRealmStrategies*

(*denotesnon-statutoryplans)

1. County Development Plans

Thepromotionofsustainablesettlementandtransportation strategies in urban and rural areasaspartofdevelopmentplanshallbeinformedbytheprinciplesinthisManual.

2. Local Area Plans

LocalAreaPlansshallbeunderpinnedbyanassessmentoftransportationandmobilityintherelevantarea.Thiswillinformtheformulationofpoliciesaimedat:1

• Promotingawalkingandcyclingenvironment.

• Creatinghighlevelsofconnectivity,particularlyformoresustainableformsoftransportation.

• Land use and transport integration to reducecardependency.

• Parkingforcyclesandcars.

Theimplementationofthesepoliciesshould

1 RefertoSection5.6AchievingSmarterTravelofthe Local Plans Planning Guidelines(2013).

bereflectedinarangeofstrategiesthataddress broader movement and place considerations, such as:

• Major connections• Vehicle circulation• Publictransportroutes• Cycleroutes• Pedestrianroutes.

Such strategies should be illustrated via a numberofdiagramsthatindicatethebasisofanyfuturestreetnetwork(seeSection3.3.1StreetLayouts).

LAPsshouldalsobeusedtoaddressmoredetailed matters such as those contained withinChapter4.SuchissuesmaybeaddressedviaUrbanDesignCodes2 which set outaseriesofprescriptivemeasurestowhichdevelopment should adhere. With regard to streetdesignthesemaytaketheformofcrosssectionsandtypologies(seeFigure5.2)and/ormayincludedetailedillustrationsrelatingtoaparticularplace(seeFigure5.3)

3. Masterplans

Masterplans,likeLAPs,areusedtoprovideamoredetailedframeworkforareaswheresignificantchangeordevelopmentisanticipated.MasterplansmayalsoactasacompanionguideorsubsetofanLAP.SuchMasterplansareoftenreferredtoasanUrbanDesignFrameworks.

MasterplansmaycontainagreaterlevelofdetailthanLAPsandmayalsoincludemorecomprehensive guidance on the design ofindividualstreets.Forexample,whilststreettypologiesmaybeprovidedinanLAPdocument,theyareasignificantcomponentofaMasterplan.

2 The LAP Guidelines (2013)recommendtheincorporationofcross-sectiondiagramsofstreetsandjunctionswithinLAPs.


Further guidance on the role, scope and contentofMasterplansmayalsobesoughtfromGuidelines for Planning Authorities on Sustainable Residential Development in Urban Areas (Cities, Towns & Villages) (2009)3 and the UK Creating Successful Masterplans (2004).

4. Movement Frameworks

MovementFrameworksareaformofMasterplanthatareprimarilyconcernedwithissuesrelatingtothemobilityandmanagementofuserswithinastreet/roadnetwork.AMovementFrameworkmayfocusonthebroaderstructural/strategicaspectsofmovementaswellasmoredetailed considerations. A comprehensive MovementFrameworkmayalsoincludeatrafficmanagementstrategythatmodelsthemovementoftrafficwithinanetwork.AlthoughaMovementFrameworkisprimarilyfocusedonthefunctionalityofastreet/road network, such plans should also take into account the interrelationship between movement and place.

5. Public Realm Strategies

PublicRealmStrategiesmayaddressbroaderstrategicissuessimilartoanLAPorMasterplan,buttheyaremorecloselyassociatedwith detailed design outcomes. In some casesPublicRealmStrategiesmayincludedetailed material palettes and construction specifications.Examplesofpublicrealmstrategieshavebeenpreparedbyvariouslocalauthoritiesincluding,DublinCity,WicklowTownandCastlebar(seeFigure5.4).

3 RefertoSection2.13oftheGuidelines for Planning Authorities on Sustainable Residential Development in Urban Areas (Cities, Towns & Villages) (2009).


Figure 5.2: The Newcastle LAP (2012) is an example of a Local Area Plan where a series of strategic connections are proposed to shape the future expansion of the village. These connections are further detailed through a series of Urban Design Codes in the form of a street hierarchy, cross section and layouts (street typologies).

Figure 5.3: Extracts from the Kilfinane LAP (2012) illustrating a number of streetscape improvements that better define the street as a place.

Kilfinane Local Area Plan Section Seven: Site Development Briefs

59

Kilfinane Local Area Plan Section Seven: Site Development Briefs

58

Arterial/Main Street

Neighbourhood Link

Local Access Street


Figure 5.4: Extracts from the Castlebar Town Centre Regeneration Project

AnexampleofadetailedPublicRealmStrategy.Castlebar town was described as being characterised byvisualclutter,poorpedestrianinfrastructureandanexcessivevehiclepresence.Theworkshavesignificantlyimprovedtheplacevalueofthetowncentreandcreatedasenseofsharedspacewith‘asafepedestrianenvironmentalongwithsuppressedvehicledominance’.

BEFORE

AFTER


5.2.2 Development Rationale

Toeffectivelycommunicatehowtheprinciples, approaches and standards within this Manual have been applied, it is recommended that all proposed developments,regardlessofscale,areaccompaniedbydocumentationthatprovidesaclearrationalefortheproject,suchas within a design statement4, including:

• Aclearsetofobjectivesfortheproject(seeSection5.3.2Process).

• Howcontextandfunctionweredetermined(seeSections3.2.1MovementFunctionand3.2.2Context).

• Strategic drawings outlining the structure ofthestreetnetwork(seeSection3.3.1StreetLayouts).

• Detailedstreetlayoutsthatclearlyillustrateall relevant geometric standards and other treatmentsaimedatpromotingasenseofplace,sustainableformsoftransportationandtrafficcalming.

• A comprehensive auditing process (see Section5.4Auditing).

Toensurethatstreetlayoutplanscommunicateacompletepictureofthedesign,itisrecommendedthatthefollowinginformationbepresented,asappropriate(seeFigure5.5):

• Thewidthofstreets,footways,verges,mediansandprivacystrips.

• Thelocation,typeandconfigurationofcrossings and junctions.

• Corner radii (including swept paths).

• On-streetparking.

• Horizontal and vertical alignment data.

• Horizontalandverticaldeflections.

• Forwardvisibilitysplays.

• Kerb lines (including heights).

4 RefertoSection3.10oftheGuidelines for Planning Authorities on Sustainable Residential Development in Urban Areas (Cities, Towns & Villages) (2009).

• SurfaceMaterialsandPlanting.

• Streetfurnitureandfacilities.

• Signage and Line Marking.

• Lighting.

Designteamsandplanningauthoritieswillneedtobalancethelevelofdetailgivenatanystageofthedesign/consentprocess.Forexample,moretechnicalspecificationsmaybebettersuitedtolatercompliancesubmissions so that the initial consent process isnotoverlyburdenedwithdetail.Suchspecificationsmayincludematterssuchasfinalmaterialpalettes,constructiondetailsandplantingschedules.Theyshouldbematterswhichdonotaffecttheamenitiesofathirdparty,withoutthatpartyhavingtherighttocomment on the compliance submission followingthegrantofpermission.


FIGURE 5.5: EXAMPLES OF DETAILED DRAWINGS

Street Design Layout Plan illustrating street types and fundamental elements of the street geometry. Drawing by WSP based on design by Henry J Lyons Architects.

Landscape Plan illustrating surface materials and planting materials. Drawing by Gross Max landscape architects based on design by Henry J Lyons Architects.


5.3 Multidisciplinary Design Processes.

5.3.1 Design Team

The design team should include a broad rangeofprofessionalswithvaryinglevelsoftechnical expertise in streets/road design (see Figure5.6).Thefinalmake-upofadesignteam will depend on the resources available andthescaleoftheproject.Designinputshouldideallybesoughtfromarangeofskillsets to ensure that a holistic design approach isimplemented.Asthescopeofprojectsbroaden, or in response to particular issues, designinputmayalsobeneededfrommorespecialisedskillsets.Forexample,ifdesigningwithin a historic context, input should be soughtfromaconservationexpert(seeFigure5.7).

A project manager should be appointed to oversee sizable or complex projects. Theprojectmanagermaycomefromanybackgroundassociatedwiththedesignofthebuilt environment. It is recommended that the project manager has extensive experience incriticallyanalysingandevaluatingadvicefromarangeofdesignprofessions.

Onlargerscale,orhighprofileprojects,itisrecommendedthataDesignChampionbeassignedtotheproject.TheUKDoTrecommendsthattheDesignChampionnotformpartoftheday-to-dayworkinggroup within the design team.5 Rather the DesignChampionshouldassisttheteamindevelopingavisionandsetofdesignobjectivesfortheproject,ensuringthattheseare adhered to and promoting them to thebroadercommunity,includingelectedrepresentatives.

Theformationofamulti-disciplinaryteamiscriticalfortheassessmentofanyproject.Whilsttheformalassessmentandconsentprocessfordifferentdesignprojectsmayvary,itisessentialthattheyhavemulti-disciplinaryinputsothattheycanbefullyassessedagainstthebroadrangeofprinciples,approachesand standards contained within this Manual, particularlywhereanyconflictsofplaceandmovementmayarise.Toassistthisprocessitisrecommendedthatmulti-disciplinaryprofessionalteamswithinplanningauthoritieswork together as a cohesive unit.

5 ReferSection2.10ofLocal Transport Note 1/08 Traffic Management and Streetscape (2008).

Range of Inputs Required

Required

EngineeringTown PlanningUrban Design*

Desirable

ArchitectureLandscape Architecture

As required

Heritage SpecialistConservation SpecialistEnvironmental Specialist

*Mayalsoincludeanarchitect,engineer,landscape architect or town planner with urban design skills.

Figure 5.7: The range of skill needed for input into a multidisciplinary design team. Skill sets have been ranked to indicate where resources should be prioritised and where additional input may be desirable.

Figure 5.6: Extract from Local Transport Note 1/08 showing how a range of technical skills contribute to the design process.


Figure 5.8: The key stages of the design process.

Analysis and Vision

Design/Refine

Consultation Constructionand Monitoring

5.3.2 Process

Thereseveralguidelinesthatprovidein-depthadviceoncollaborativemultidisciplinarydesign processes. These include the Manual for Streets (2007), which outlines a process formulti-disciplinaryteamsforprojectsofvarious scales6andtheUKDepartmentforTransport Local Transport Note 1/08 - Traffic Management and Streetscape(2008), which focusesoncollatingandcoordinatinginputsofarangeofdesignersunderthedirectionofaprojectmanager.The‘InPractice’sectionoftheUrban Design Manual (2010) alsooutlinesaprocessforthepreparationofplanningapplications.Figure5.8illustratesasimplifiedprocessthatincorporatesfourkeystagesforadesignteam,asdiscussedbrieflybelow.

6 RefertoTable3.1ofthe UK Manual for Streets (2007)

Analysis and Vision

Thefirststagesofaprocessshouldbetoundertakeananalysisandestablishtheobjectivesfortheprojectsothatthedesignteamhasaclearunderstatingofthetaskahead.

Collectinginformationforasiteanalysiswillgenerallyconsistoftwoparts:

• adesktopstudywhereallrelevantplans,policiesandpreviouslycollectedinformationaboutaprojectiscollatedand reviewed.

• anon-sitestudywhereobservationsaremade and data is collected.

Keyinformationfortheprocessincludes:

• Plansandpolicies(relevantnational,regional and local plans).

• Spatial characteristics (such as land uses, destinations,densities,activitygenerators).

• Movementpatterns(suchasusermobility,keydesirelines,obstructions,publictransport).


• Builtform(enclosure,interface,streetgeometry).

• TrafficSurvey(suchastrafficcounts,carparking).

• Topographyandlandscape(suchasslopes,plantingandecology).

• Heritage and conservation (where appropriate).

AkeyoutcomeoftheanalysisprocessshouldalsobetheidentificationoftheContext(s) oftheprojectandtheFunction(s)ofthestreet/street network. Further guidance on siteanalysismayalsobetakenfromtheUrban Design Manual (2010).7

Theanalysisprocessshouldprovideasolidunderstandingoftheissuesthatneedtobeaddressed.Oneofthefirststepsinformulatingaresponseistoestablishaclearvisionthataddressescoreissuesofplaceandmovement.Avisionfortheprojectwillenabletheformationofasetofobjectivesthatactsasa‘missionstatement’.Thiswillsetthecontextfortheapplicationofmoredetaileddesign.Objectivesmayrelatetoanumberofaspectsofanydesign,suchasthecharacteroftheplace,levelsofconnectivityfordifferentusersandtrafficcalming.

Theobjectivesofaschemeshouldbereferredtothroughoutadesignprocess,andmayalsoformthebasisofaformaldesignbrief.8

7 Refertothe‘InPractice’sectionofthe Urban Design Manual (2010).

8 Refer to Part 3.8 of the Guidelines for Planning Authorities on Sustainable Residential Development in Urban Areas (2010)andtheInPracticeSectionofthe Urban Design Manual (2010).

Consultation

Severalstagesofconsultationmaybeundertakenbydesignersdependingonthetypeandscaleofaproject.Itisrecommended that designers undertake consultationasearlyaspossible.Designersmayengagewithacommunityand/orroadsauthoritypriortoanydetaileddesignworktakingplace,toidentifyfurtherissuesandtogaugetheaspirationsofthecommunity(tofurtherrefinetheobjectivesfortheproject).Aworkshopenvironmentmayencourageparticipantstoplayanactiveroleintheinitialdesignoftheproject.Furtheradvicetoassistdesignerswithmorein-depthcommunityinvolvement,particularlyattheearlystagesofadesignprocess,isavailablefromtheUKRoyalTownPlanningInstitute9andUKPlanningAdvisoryService.10

It is also recommended that designers undertakepre-planningmeetingswhereadesignistobesubmittedtoalocalauthority.Boththedesignteamandthelocalauthorityshould ensure that this occurs within a multidisciplinaryenvironmenttoensurethatabroadrangeofissuesareconsidered.Thedesign team should ensure that all relevant design disciplines are present. The local authorityshouldensurethatallrelevantdisciplines are represented.

Design and Refine

Theoptimalsolutionisrarelyachievedonafirstattemptandislikelytoemergeovermanydrafts,havingbeeninformedbyasolidanalysisandappropriatelevelofconsultation.Athoroughdesignprocessislikelytoinclude:

• Productionofstrategicleveldrawingsthatillustratethekeyroutesandlinkswithin a street/streetnetwork(seeSections3.3.1StreetLayout).

• Typologiesorconceptualindividualstreetdesigns.

• Initialdetaileddesignandrefinementpreparedtoaprofessional/technicalstandard.

9 RefertoUK Guidelines on Effective Community Involvement and Consultation: Good Practice Note 1 (2005).

10 Refer to UK Community Engagement in Plan Making (2010).


• Designfinalisationandformalconsentprocess.

The optimal time to undertake an audit process is when the design has reached a stagewheretheoutcomescanbeclearlyevaluated,suchasafterinitialrefinementandpriortofinalisation.Thiswillalsoallowthedesigntobeformallytestedagainsttheobjectivesoftheprojectandwithregardtoothercriticalmatterssuchassafety(seeSection5.4Auditing).

Oncethedesignisfinalisedandalltherelevant approvals have been granted it must notberetrospectivelyrevisedinamannerthatwould contradict the approved plan at later stages.Anypotentialfuturetakinginchargeissuesrelatedtodesigngeometryandlayoutsshouldbefullyresolvedaspartoftheconsentprocess.

Construction and Monitoring

Thedesignphasewilllargelyconcludeonceanyrelevantapprovalshavebeengrantedandalltechnicalspecificationshavebeenformalised,itisrecommencedthatthedesignteam participate in the project through to itscompletionandperiodicallymonitoritsperformance.

Duringtheconstructionphaseitisrecommended that the design team/planning authoritiescarryoutperiodicinspectionstoensure that the project is being carried out in accordance with the approved design. This willnotonlyassistinensuringtheobjectivesoftheprojectarefullyimplemented,butwillreducethepotentialforerrorandabortiveorwastefulworks.

Periodicmonitoringisrecommended,particularlywhereinnovativedesigntechniques and/or untested materials have beenused.Post-constructionperformancemonitoringshouldbefocusedonthesafetyrecord and vehicle operating speeds to ensure that project objectives have been met.Designteams/roadsauthoritiesareencouragedtomakesuchfindingspubliclyavailablesoastoaddtothegrowingbodyofworkthatinformsmoreintegrateddesignsolutions.

Theissueofmaintenanceisalsoofprimaryconcernformanyroadsauthorities,particularlywherehigherspecificationmaterialsareused.ManylocalauthoritieswithintheUKhaveissuedspecificstreetscapedesignguidancethatdetailapaletteofstreetfurniture,materialsandfinishesthatareacceptable to planning authorities.11PartBoftheAdamstown Street Design Guide (2010)alsoprovidesexamplesofacceptedstandards. It is recommended that local authorities collate and issue similar guidance toencouragebetterquality‘workmanship’andtosimplifythemaintenanceregime.

11 ExamplesincludetheCamden Streetscape Design Manual(2005) and Streetscape Design Manual for Nottingham City Centre(2006).


5.4 Auditing

5.4.1 Road Safety Audits

AuditingprocessesinIrelandaregenerallyintheformofaRoadSafetyAudit(RSA).TII has publishedasetofstandards12thatdefinetheroleof,andoutlinetheprocessforcarryingoutaRSA.TheprimarypurposeofaRSAistoidentifypotentialhazardsandhowtheycouldaffectroadusersusingthefollowingcriteria:

• Doesthedesignlayoutcreateconfusionorambiguityforroadusersthatcouldleadtopotentialroadtrafficaccidents?

• Is there too much, or too little informationforroadusers?

• Istheretoolittle,ortoomuchvisibility,oranobstructiontoroadusers’view?

• Doesthelayoutcreatehazardsorobstacles to road users that could contributetoanincreasedriskofinjuries?

Iftheansweris‘yes’toanyofthesequestions,thenitisdeemedthatthesafetyofthescheme could be compromised and remedial measuresmayberequiredtoremoveapotentialoractualdeficiency.

WithinIrelanditismandatorytocarryoutaRSAonanypermanentchangetotheroadlayoutonNationalRoads.ThestandardiscommendedtoroadsauthoritiesforuseinpreparationoftheirownroadschemesonRegionalorLocalroads’anditiscommonpracticeforlocalauthoritiestorequireanRSAforallroadschemes.Circular RLR 16/2008, Road Safety Audits and Road User Audits issuedbytheDepartmentofTransportalsorequiredthatroadsauthoritiescarryoutsuchauditsonschemesfundedorco-fundedbytheDepartment.

12 RefertoGE-STY-01024RoadSafetyAudit(2017).

TheimplementationoftheManual for Streets (2007) intheUKhasraisedmanyissuesinrelationtotheapplicationofRSA.TheseissuesarealsofurtheraddressedintheUKManual for Streets 2 (2010).13 These manuals note that theapplicationofRSAstandardsrequireadifferentperspectivewhenappliedwithinanintegrated street environment. Concerns are raised that the RSA process is predisposed to segregated/conventional design solutions that maydetractfromthesenseofplace,reducelevelsofpedestrianamenityand,insomecases,actuallyreducesafetylevels,as‘wheretheappearanceisoneofsafety,individualsmaydroptheirguardandaccidentsensue’.14

ToreducethepossibilityofconflictwiththisManual,theauditteamresponsibleforcarryingoutaRSA:

• Musttakefullcognisanceoftheprinciples,approaches and standards contained within this Manual.

• Shouldnotrecommendanyactionsthatwillreduceeaseofmovementforpedestrians/cyclistsinfavourofmotorvehicles or seek to add or remove measuresthatmayresultintheoperatingspeed exceeding the intended design speed.

• Shouldpromotethecreationofaself-regulating street environment.

• Shouldhaveaclearunderstandingoftheobjectivesofthedesign.

The RSA should, where appropriate, also be partofalargerQuality Audit(seeSection5.4.2QualityAudits),thismayassistinidentifyingmanyoftheissueshighlightedabove.

13 RefertoSections3.7oftheUK Manual for Streets (2007)and4.5ofthe UK Manual for Streets 2 (2010).

14 RefertotheUKHighway Risk and Liability Claims: A Practical Guide to Appendix C of the Roads Board Report (2009).


Theauditprocessmayincludedirectcommunication between the audit team and designteamifclarificationisrequiredonanyoftheaboveissues.Thiscanbeachievedthrough the existing RSA procedures. This process will allow the design team the opportunitytoclarifyanycontentiousissuesandgainfeedbackonanyalternativecoursesofaction,priortothefinalisationofthedesign.

Theauditteamshouldalsocarryoutariskassessment,15 ranking both the audit problems and the audit recommendations. Thisprocessmayassistinidentifyingthelevelandtypeof‘risk’associatedwithapotential‘hazard’.Thisisofparticularimportance on schemes where elements ofriskareintroducedtocalmtrafficandcreateaself-regulatingstreet.Inthisregarddesignteams/auditteamsmayalsorefertothethirdeditionoftheUKInstituteofHighwaysandTransportationRoad Safety Audit Guidelines(2008),producedfollowingthepublicationoftheUKManual for Streets (2007). This document also includes a Risk Assessment process that takes into account thelikelyseverityofoutcomeandfrequencyofoccurrencethatisattributabletoanyperceived hazard and notes that an auditor should:

‘not assume that behaviour on roads willnecessarilybedisplayedonstreets’

and;

‘the emphasis within Audit should beontryingtoassesswhattypesofcollisionsmayoccur’.

15 RefertoGE-STY-01027RoadSafetyAuditGuidelines-Section 4.2 Risk Assessment


5.4.2 Quality Audits

A Quality Audit should be undertaken to demonstrate that appropriate consideration hasbeengiventoalloftherelevantaspectsofthedesign.TheUKDepartmentforTransportnotesthekeybenefitsofaQuality Audit as:16

• A transparent process that demonstrates thattheneedsofallusergroupsandthedesign objectives.

• Enablestheprojectsobjectivestobedeliveredbyputtinginplaceacheckprocedure.

• Contributestocostefficiencyindesignand implementation.

• Encouragesengagementwithstakeholders.

Quality Auditsgenerallyconsistofanumberofindividualandoverlappingauditsthatmayinclude:

• anauditofvisualquality;

• areviewofhowthestreetis/maybeusedbythecommunity;

• aroadsafetyaudit,includingariskassessment;

• an access audit;

• a walking audit;

• acycleaudit;

• anon-motoriseduseraudit;

• acommunitystreetaudit(inexistingstreets); and

• a place check audit.

16 RefertoUKDepartmentforTransport Traffic Advisory Leaflet 5/11- Quality Audits (2011).

The extent to which these processes are undertakenwillvaryaccordingtothescaleandscopeofanygivenproject.TheintentionofaQualityAuditisnotto‘pass’or‘fail’adesign. Rather it is intended as an assessment tool that highlights the strengths and weaknessesofadesignandadocumentedprocessofhowdecisionsweremade.Seealso Advice Note 4 - Quality Auditsforfurtherinformation.

APPENDICES

Active StreetsStreetswherebuildingedges/frontagesareorientatedtoward,andaredirectlyaccessiblefrom,thestreetbyfoottopromotepedestrianactivity.

AnimationThecreationofaninterfacewiththestreetviaarangeofarchitecturaltreatmentsthatpromotethephysicalandvisualaccessibilityto interior activities, such as openings and shopfronts.

BoulevardAstreettypethatgenerallyconsistofwell planted medians and/or verges thatprovideabufferbetweenaheavilytraffickedcarriagewayandthesurroundingenvironment.

CarriagewayThesectionofastreetorroadthatisprimarilyusedbymotorvehicles(butmayalsobeusedbypedestriansandcyclists).

ConnectivityHoweasilyanddirectlyusersareabletomovethroughstreetnetworks(seealsoPermeabilityandLegibility)

Corner RadiiThemeasureofhowbroadortightcornersareatajunction,measuredfromtheoutsideofakerbortheoutsidelineofacyclelane(wherepresent).

Cul-de-sacA street or road which terminates without connecting to another street (see also Vehicular Cul-de-sac)

Cycle FriendlyAstreetenvironmentdesignedtoallowcycliststomoveaboutinsafetyandcomfort.

Design SpeedThe maximum speed at which it is envisaged/intendedthatthemajorityofvehicleswilltravel under normal conditions.

Desire LinesNormallytheshortestroutefromoneplaceto another, but can be the most convenient, easytouseorcomfortableroute.

Enclosure (Sense of)Aconditioncreatedbyprovidingacontinuouslineofbuildingsand/orstreettreesthathastheeffectofcalmingandcreatingagreaterperceptionofsafety,especiallyforpedestrians.

FootpathsThe area within a street reserve that is generallyreservedforpedestrianuse.

FootwayThemainsectionofthefootpathalongwhichpeople walk.

HomezoneAtypeofShared Surface Street in a residential areawhichmayalsoincludeitemsofstreetfurniturethatwouldnormallybeusedwithinareasofopenspaces.

Horizontal AlignmentHorizontalalignmentreferstothedirectionaltransitionofaroadorstreetinthehorizontalplane. In essence a horizontal alignment consistsofstraightsectionsjoinedbycurves.

Horizontal DeflectionsChanges that occur within the horizontal alignmentofthecarriageway,suchaspinchpoints, which slow vehicles and require drivers to change direction.

Human ScaleAperson’sperceptionofthesize,scale,height,bulkand/ormassingofbuildingsandotherfeaturesofthebuiltenvironment.

GLOSSARY

Integration (Integrated Streets)Streets where real and perceived barriers to movementwithinandbetweenmodesoftransport are removed to promote improved interactionbetweenusersinasafeandtraffic-calmed environment.

An integrated approach to street design also includesamoreholisticviewofthestreetanda more collaborative approach its design wherefactorssuchasthetypeofplaceandneedsofallusersaretakenintoaccount.

Integrated Street NetworksHighlyconnectedstreetnetworksthatsupporttheintegrationoflanduseandtransportation.

LegibilityThe ease in which user can navigate a street orstreetnetworkusingseriesofenvironmentalcues such as buildings, landscape treatments, materialsandfinishes.

Mixed UseA development, street or broader area that containsarangeofdifferentlanduses.

Modal ShiftAchangeinthemethodoftransportationusedbypeople.

Multidisciplinary ApproachA collaborative approach to design where the skillsofanumberofdesignprofessionalareutilised to produce a design.

Naked Street(s)A street or street network in which there is little ornoregulatorysignageandlinemarking.

NodesMajorplacesofconvergenceandinterchangebetweendifferentformsoftransportation.

Passive SurveillanceOverlookingofstreetsandspacesfromadjoining buildings.

Pedestrian FriendlyA street environment designed to make pedestriansfeelsafeandsecureandallowthem to move about with relative ease.

Place (Sense of)Thecharacterorcharacteristicsofanareainrelationtohowitisperceivedbyauser.

Pedestrianised StreetsStreetsthataredesignatedforpedestrianuseonly,althoughemergencyaccessandlimitedaccessforservicevehiclesisprovided.

PermeabilityThedegreetowhichanareahasavarietyofpleasant,convenientandsaferoutesthroughit.

Self-Regulating StreetA street where the environmental conditions and/orseriesofdesignmeasuresareusedtoinfluencedriversbehavior,minimisingtheuseofphysicallyintrusivemeasuresorlargeamountsofregulatorysignageandlinemarking.

Segregated Street NetworksStreetnetworkswherethemovementofdifferentmodesoftransportarerestrictedtoaparticular route based on purpose, destination and/ortype.

Segregation (Segregated Streets)Streets within which interactions between modesoftransportarediscouragedorpreventedthroughtheuseofaseriesofbarriers and other design measures.

Severance Wheretheprovisionofroadinfrastructure(e.g.adistributorstyleroad)bisectsanarea,making people movement within the area moredifficult.

Shared Space (Sense of)See Integration

Shared Surface Streets Astreetwherepedestrians,cyclistsandvehiclessharethemaincarriagewayandwherepedestrianshavepriorityofmovementover other uses.

Speed (Very Low, Low, Moderate and High)Describedwithinthecontextofcites,townsandvillagesasverylow(<30km/h),low(30km/h),moderate(40-60km/h)andhigh(>60km/h).

Stopping Sight DistanceThe distance ahead a driver needs to see inordertostopsafelyshouldanobstructionenter their path.

Street FurnitureItems placed within the street with the purpose ofdirectingmovementand/orenhancingits place value including public art, lighting, bollards,guardrails,seatingandcycleparking.

Sustainable Modes of TransportationTransportation which has a lower impact on theenvironmentincludingwalking,cyclingand public transport.

SustainabilityMeetingtoday’sneedswithoutcompromisingtheabilityoffuturegenerationstomeettheirneeds.

Sustainable Urban DrainageAdrainagesystemwhichseekstoemulateorrestoringamorenaturalhydrologicalregimesothattheimpactofurbanisationondownstreamfloodingandwaterqualityisminimised.

Updesign(ing)Theapplicationofstandardsintendedforhigherorderroads/streetsthatdetractfromthesenseofplaceandinappropriatelyincrease design speeds.

Vertical AlignmentVerticalalignmentreferstothechangeinelevationofaroadorstreetalongit’slongitudinalprofile.Averticalalignmentconsistsofaseriesofstraight-linegradientsthatareconnectedbycurves.

Vertical DeflectionsChangesinlevelonacarriageway,suchasraised tables, designed to slow vehicles.

Visibility SplaysVisibilitysplaysareprovidedatjunctionsto provide sight lines towards and down intersecting streets to ensure that drivers havesufficientreactiontimetostopshoulda vehicle enter their path (see also Forward Visibility and Stopping Sight Distance)

Vulnerable UsersRoaduserswhoaremostatrisk–pedestriansandcyclists,specificallychildren,theelderlyandpeoplewithmobilityimpairments.

Adamstown Street Design Guide. 2010. South DublinCountyCouncil.

Air Quality in Ireland.2009.EnvironmentalProtectionAgency.

An Evidence Based Approach to Crime and Urban Design. 2009. Hillier and Sahbaz.

Architectural Heritage Protection Guidelines for Planning Authorities.2011.DepartmentofArts,HeritageandtheGaeltacht.

Camden Streetscape Design Manual. 2005.LondonBoroughofCamden

Car Parking: What Works Where? 2006.EnglishPartnerships.

Circular RST 02/2011: Guidelines for the Setting of Special Speed Limits.2010.MinisterforTransport.

Community Engagement in Plan Making. 2010. PlanningAdvisoryService(UK)

Compensation Culture.2006.HouseofCommonsConstitutionalAffairsCommittee.

Designs for Life: Learning from Best Practice Streetscape Design. 2007. Marceau, Bradbury,Hickman,Hamilton-Baillie.

Design Manual for Roads and Bridges. 1992. DepartmentforTransport(UK)

Designing Streets. 2010.ScottishGovernment.

Designing the Future: Shared Space Qualitative Research. 2010.DepartmentforTransport (UK).

DfT Shared Space Project Stage 1: Appraisal of Shared Space.2009.DepartmentforTransport (UK).

Effectiveness of Green Infrastructure for Improvement of Air Quality in Urban Street Canyons.2012.Pugh,MacKenzie,Whyatt,Hewitt(LancasterUniversity).

Fairness in Transport: Finding an alternative to car dependency. 2011. Sustainable DevelopmentCommission.

Free Speed Survey (Urban and Rural). 2008.2009. 2011. RoadsSafetyAuthority.

Greater Dublin Area Draft Transport Strategy 2011-2030.NationalTransportAuthority.

Greater Dublin Strategic Drainage Study. 2005.DublinDrainageConsultancy.

Guidelines for Planning Authorities on Sustainable Residential Development in Urban Areas (Cities, Towns & Villages). 2009. DepartmentoftheEnvironment,HeritageandLocalGovernment.

Guidelines on Effective Community Involvement and Consultation: Good Practice Note 1.2005.RoyalTownPlanningInstitute(UK).

Guidance on the Assessment of Pedestrian Guardrail. 2012.TransportforLondon.

High Risk Collision Sites and Y Distance Visibility. 2010.TMSConstancy.

Highway Risk and Liability Claims, 2nd Edition. 2009.HighwayLiabilityJointTaskGroup(UK).

Improving Traffic Behavior and Safety through Urban Design.2005.JonesandHamilton-Ballie.

Layout and Design Factors Affecting Cycle Safety at T-Junctions. 1992. Henson and Whelan.

Life Between Buildings. 1971.JanGehl.

BIBLIOGRAPHY

(Draft) Local Area Plans: Guidelines for Planning Authorities. 2012.DepartmentforEnvironment,CommunityandLocalGovernment.

Local Transport Note 1/08: Traffic Management and Streetscape.2008.DepartmentforTransport(UK).

Local Transport Note 2/09 Pedestrian Guardrailing.2009.DepartmentforTransport(UK).

(Draft) Manual for Local Area Plans: A Companion Document to the Guidelines for Planning Authorities on Local Area Plans. 2012. DepartmentforEnvironment,CommunityandLocalGovernment.

Manual for Streets.2007.DepartmentforTransport (UK).

Manual for Streets 2 - Wider Application of the Principles. 2010.TheCharteredInstitutionofHighwaysandTransportation(UK).

Manual for Streets: Evidence and Research (TRL Report 661).2007.DepartmentforTransport (UK).

Manual for Streets: Redefining Residential Street Design.2006.TransportResearchLaboratoryLtd.

National Cycle Manual. 2011. National TransportAgency.

National Roads Authority Design Manual for Roads and Bridges.2013.NationalRoadsAuthority.

Natural Stone Surfacing: Good Practice Guide (SCOTS Guide). 2004.SocietyofChiefOfficersofTransportinScotland.

Parking: What Works Where. 2006.EnglishPartnerships.

Paved with Gold: The Real Value of Good Street Design.2007.CommissionforArchitectureandtheBuiltEnvironment(UK).

Paving: the Conservation of Historic Ground Surfaces. Forthcomingin2013.DepartmentofArts,HeritageandtheGaeltacht.’

Pedestrian Crossing Behaviour at Signalised Crossings.2008.DepartmentforTransport(UK)andImperialCollegeofLondon.

Planning Advice Note 81: Community Engagement in Plan Making.2010.PlanningAdvisoryService(UK).

Psychological Traffic Calming. 2005.TransportResearchLaboratory.

Residential Density Guidelines. 1999. DepartmentoftheEnvironmentandLocalGovernment.

Road Safety Audits. 2012.Partof NRA DMRB Volume 5, Section 2, Part 2 NRA HD 19.

Roads in Urban Areas.1966.MinistryofTransport (UK).

Road Safety Planning: New tools for Sustainable Road Safety and Community Development.2007.GordonLovegrove.

Smarter Travel - A Sustainable Transport Future: A New Transport Policy for Ireland 2009 - 2020. 2009.DepartmentofTransport.

Spatial Planning and National Roads: Guidelines for Planning Authorities. 2012. DepartmentofEnvironment,HeritageandLocalGovernment.

Streetscape Design Manual for Nottingham City Centre. 2006.NottinghamCityCouncil

The Visual and Social Problems of the Design of Residential Areas Today.1976.RuairiQuinn,‘StreetsforLiving’Conference.

Traffic Advisory Leaflet 5/11 Quality Audits. 2011.DepartmentforTransport.

Traffic in Towns (also known as the Buchanan Report).1963.MinistryofTransport(UK).

Traffic Management Guidelines.2003.DepartmentofTransportandDepartmentoftheEnvironmentandLocalGovernment.

Traffic in Villages: Safety and Civility for Rural Roads. 2011.DorsetAreaofOutstandingNaturalBeautyPartnershipandHamilton-Baillie Associates.

Traffic Signs Manual. 2010.DepartmentofTransport.

Understanding Walking and Cycling. 2011. EngineeringandPhysicalSciencesResearchCouncil.

Urban Design Compendium. 2000.EnglishPartnerships.

Urban Design Manual: A Best Practice Guide. 2009.DepartmentofEnvironment,HeritageandLocalGovernment.

Walking in Towns and Cities. 2011. UK ParliamentInquiry.

Whose Street is it Anyway? Redefining Residential Street Design.2006.TransportResearchLaboratory.

INDEX

Block sizes 44, 51

Buildingfrontages 7, 9,26-27,66,68,72-73, 86

Building height 47, 69-70

Bus gates 52,56 lanes/routes 34,42,50,56,90,93, 101-102,105 travel 15,20,28,54,55,104

Car parking dimensions 120-121 on-street 7,17,18,21,22,46,53, 56,65,87-88,100,101, 109,110,115,117-121 off-street 73, 87,88

Carriageway Alignment 107, 110-113, 114-115 Widths 21,24,35,56,94,99, 101-102,115,119,121

Classificationofstreets See Function Clutter 21,74-76,77,80,81,100, 129

Connectivity SeeStreetLayoutsand Permeability)

Context(ofplace) 37-40,63-68

Cornerradii SeeJunctions

Cul-de-sacs 7,18,41,44,52

Cycle lanes/tracks 21,53,81,87,88,99-100 parking 77-78,109 transportation6,7,15,28,41,42,52, 54,105-106,109,126

Designteams 132

Distributorroads 17-18,19-20,22,55,119

Emergencyvehicles 95,96,115

Forwardvisibility 84,107,108-109, 110-113,114-115

Front gardens 73

Function(ofstreets) 6,7,9,17,19,24,26, 35-36,63-68

Gradients 112,113

Guardrails 20,21,23,75,77-78,95, 109

Historicitems/settings 48,77, 85, 96,103,132

Homezones 7,96

Horizontal Alignment and Curvature 110-111

Impairedusers 97-98,113,114,116

Junctions cornerradii 66,90,93-95, 104-105, 116 congestion 54-55 frequency 19,22,50-51,55,66,113 layout/type 90,96-97,100,104-106, 114-115 priority 8,20,23,24,26,54-55, 56,90,91 visibilitysplays88,107,108-109

Kerbs build-outs 80,83,91,116,118,121 lines 115,116 heights 97,98,103,106,116 mounting 21,78,117

Landscaping 46,47-48,77,83-84, 120-121,131

Legibility 7,19,20,41, 47-49,52, 70,71,81,84,110,114

Lighting 71, 77, 79-80,86,109, 118

LocalAreaPlan 9-10,126,128

Maintenance 24,82,135

Masterplans 9,126

Materialsandfinishes 47,49,81-82,83,85,87, 97,103,118,131,135

Mobilityimpaired seeImpairedusers

Monitoring 133,135

One-waystreets 17,53

Pedestrian activity 27,38,63,66,68,79,82, 83,86, 90,113 barriers 20,21,23,46,75,77-78, 81,82 crossings 8,20,23,24,27,40,54, 55,66,77,78,82,89-92, 97,103,104-106,114, 116,118 environment 7,18,19-24, 41,43,44, 45-46,47,48,51,52,53, 57,59,68,69,72,86-88, 96,103,116,129 footpaths 7,86-88 priority 9,16,26-27,28,33,35, 37-40,52,54-55,64,89- 91,104,106,114 safety 6,7,9,18,20,22-23, 63- 64,69,72,79-80,89,93, 103,104,105,118,136 onlystreets 96-99 Place context 37-40 making 9, 26-27,41-42,48,53, 59-60,66,69,71,72,74- 75,77- 78,79,81-82,83- 84,96-97,103,109,113, 117, 119, 128-129,136 senseof 4,7,18,25,51,57,59- 60,85, Placeand Movement 35-40, 56,63-68

Planningprocess 10-11,130,132,134-135

Planting SeeLandscaping

Publicconsultation 45,134

PublicRealmStrategy126-127,129

Qualityauditing 136,138

Roadclosure seecul-de-sac

Shared-surfaces 7,9,66,68,81, 96-98, 101-102,103,104,106, 116

Signage 8,21,24,53,66,74-76, 77,80,81-82,100

Speed balance 6,22-23,63-64, 136 network 17,50,54,57,59,64 self-regulation7,49,65-68, 75,75,76, 81,93,101-102,103,107, 108,110,114-115,116, 117 Staggeredcrossings 20,55,90-91,104

Stopping SightDistance(SSD) 107,108-109,110-112 Street hierarchy 6,9,33-34,35-36,43,81, 128 furniture 8,48,76,77-80,85,86, 87,109,135 layouts 19,25,26-27,33, 41-43, 45-46,47, 54,56,70,71 lighting 79-80 networks Seelayouts

Sustainable urban drainagesystems(SUDs) 84

Surveillance 9,21-22,45,52,72,84, 96,120

Takingincharge 135

Tactilepaving 81,82,97,98

Traffic claiming seespeedself- regulation management 50-60, 127 congestion 15,17,51,53,54-55,59, 91, 104 noise 59-60

prioritisation 20,23,24,42,50,52,53, 54-55,56,91,104

Trafficsigns Seesignageandline marking

Trees 69,70,71,80,83,84,86, 87,101,109,118,119

Userhierarchy 28

Vertical Alignment and Curvature 112-113

Visibilitysplays seeJunctionsand Stopping Sight Distance

VisuallyImpaired seeImpairedusers

Width carrigeway 21,24,35,56,94,99, 101-102,115 footways 21,24,86-88 medians 91 crossings 92

Design Manual for Urban Roads and Streets

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