ITE URBAN GEOMETRIC DESIGN HANDBOOK -

URBAN COLLECTOR STREETS

Paul Mackey2004 District 1 Meeting, Burlington, VT

URBAN GEOMETRIC DESIGN HANDBOOKURBAN GEOMETRIC DESIGN HANDBOOK

Ten chaptersIn the same style as the TEH, TCDH and the TPHNew demands on design:

Health promotionWalkingCycling

Overview; design details to follow

CharacterizationCharacterization

Urban areas : population of 5,000 or moreRural areas outside the boundaries of urban areasSmall towns and villages do not easily fit this scheme

Ambiguous nature of collectorsAmbiguous nature of collectors

Local streets for accessArterials for traffic flowCollectors for both, in about equal proportionsA lot of guidance is inappropriate

Residential, commercial, industrial, institutional

Residential, commercial, industrial, institutional

A collector street may provide different services along its lengthThere is then a need to adjust the designThe design vehicle may changeCollectors are good streets for non–residential land uses or higher density housing

Typical traffic flowsTypical traffic flows

Residential collector below 8,000 vpdIndustrial/Commercial collector 1,000-12,000 vpdSingle travel lane should normally be sufficient

Access for multiple usersAccess for multiple users

Pedestrians require sidewalks in residentialand commercial areas: one side or both?Industrial areas?Institutional areas, schools in particular?Curb extensions as standard featuresBike facilities: bike route or bike lane?Transit

Choosing the optimal operating speed

Choosing the optimal operating speed

A move away from looking only at design speedIHSDMIndustrial areas 35-40 mphResidential areas 30 mphElementary school areas 20-25 mph

Designing to obtain an operating speedDesigning to obtain an operating speed

Designing up front to avoid traffic calming retrofitsUse of maximum unimpeded street length or stops can be considered for local streetsHorizontal curvatureWidth of the paved surfaceLongitudinal sight distance (also vertical curvature)Lateral sight distance

Traffic FlowTraffic Flow

Uninterrupted movement between collectors and arterialsUsually one lane at intersectionsIf more than one, refuge island to facilitate pedestrian crossingsSingle lane roundabouts at collector/collector intersections

Cross-sectionCross-section

Street width and parking: zoning by-law requirementsCurb extensionsPutting homogeneous width into questionLane width and bike facilities

Cross-section (2)Cross-section (2)

Boulevard or not – snow removalCurbs and roadside obtstructionsBus bays or bus bulbsCurb cut sidewalks or raised crosswalks

Trade-offsTrade-offs

Restrictions and trade-offs are plentifulAssigning limited ROWHelp in understanding the impacts and the trade-off process

Future stepsFuture steps

Chapter authors write their textEditorial reviewCombining the chaptersPeer review of each chapterCompletion in 2005 or 2006