Cycle 06

Neo-Traditional NeighborhoodDesign

FHWA COURSE ON BICYCLEAND PEDESTRIAN TRANSPORTATION

NEO-TRADITIONALNEIGHBORHOOD DESIGN

L E S S O N 6L E S S O N 6L E S S O N 6L E S S O N 6L E S S O N 6

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New urbanists are zealots. They proselytize theirantidote to alienation — new old-style towns — witha missionary’s fervor. And after a frustrating firstdecade bucking an automobile-driven societyunfriendly to their peripatetic ways, they are begin-ning to make great strides.

With several neo-traditional neighborhoods built,public planners are taking notice. Some are evenadjusting general plans and zoning for compactwalkable mixed-use towns. Suburban traffic engi-neers and public works officials are no longer simplyrecoiling at the prospect of pedestrian-friendly streetpatterns with narrower, gridded and tree-lined streets.

Village model showing gridded streets and clustered buildings of different typesproposed for Haymount [Virginia] development. (Photo and caption, ENR, May 9,1994.)

6.1 PurposeTraditional Neighborhood Design (TND) (also called“New Urbanism” and “Neo-Traditional Neighbor-hood Design”) is a town planning principle that hasgained acceptance in recent years as being onesolution to a variety of problems in suburbancommunities throughout the country. Traditionalneighborhoods are more compact communitiesdesigned to encourage bicycling and walking forshort trips by providing destinations close to homeand work, and by providing sidewalks and a pleasantenvironment for walking and biking. These neighbor-hoods are reminiscent of 18th and 19th centuryAmerican and European towns, along with modernconsiderations for the automobile.

This lesson includes an informa-tive article on TND/New Urbanismthat appeared in the May 1994edition of Engineering NewsRecord. It is written from anengineering perspective, but italso describes the cooperativespirit that must exist betweenplanners, architects, and engi-neers to make TND work.

6.2 “PuttingBrakes onSuburban Sprawl”Engineering News Record article,May 1994. Reprinted withpermission.


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New urbanism allows travel from one destination to anotherwithout using collector roads. (Photo and caption, ENR, May 9,1994.)

And market surveys are convincing skeptics thatsuburban residents are content living in a town thatby design nurtures both community consciousnessand the individual spirit.

“Contemporary suburbanism isolates and separates,”says Paul Murrain, an urban planner based in Oxford,U.K. Consumers are recognizing “in their hearts” thebetter quality of life offered by new urbanism, headds.

Though new urbanism is also intended for cities cutto pieces by highways, it is more the planner’sanswer to suburban sprawl and the breakdown ofcommunity caused by a post-World War II obsessionwith the automobile. Apart from nearly total depen-dence on the car, the typical suburb, with its loopingor dendritic street pattern and dead-end cul-de-sacs,“is laid out so that it can’t grow,” says AndresDuany, partner in Andres Duany & Elizabeth Plater-Zyberk Architects and Planners (DPZ), Miami. “Itchokes on itself in very short order.”

“Suburban sprawl is riddled with flaws,” Duanycontinues. Unfortunately, “all of the professions[involved in development] have sprawl as theirmodel.”

Even those who do not subscribe to new urbanismsee a need for change. “We are finally recognizingwe should plan communities, not structures,” saysCarolyn Dekle, executive director of the South FloridaRegional Planning Council, Hollywood.

“New urbanism is a return to romantic ideas of thepast and does not respond to current lifestyles,”says Barry Berkus, principal of two California firms,B3 Architects, Santa Barbara, and EBG Architects,Irvine. “But it is part of a knee-jerk, but needed,reaction to irresponsible planning that producedmonolithic neighborhoods without character.”

Duany, both charismatic and outspoken, and hiscerebral wife Plater-Zyberk are in new urbanism’shigh priesthood. To focus attention on their goals,DPZ and several others created the Congress for theNew Urbanism last year. The second meeting is setfor May 20 to 23 in Los Angeles. “We need all theconverts we can get,” says Duany, because, “inad-vertently, one thing after another prevents it.”Among these are fear of change and criticism that thenew urbanism model is too rigid – robbing theindividual residents of choice.

Regardless of criticism, converts are beginning tospill out of the woodwork. “Before my conversion, Iwas a schlock developer,” confesses John A. Clark,of the Washington, DC, company that bears hisname. “Most of my stuff was so bad it makes yourteeth ache.”

Then in 1988, after reading about neo-traditionaldevelopment, the movement’s original name, “thelight bulb went off,” says Clark. He called Duanyand soon enlisted DPZ in the campaign for Virginia’sHaymount.

There are other tales of conversion. “We wereDuanied,” says Karen Gavrilovic, principal planner inthe Loudoun County Planning Dept., Leesburg, VA.Last year, the county adopted a comprehensivegeneral plan based on new urbanism, which just wonan American Planning Association award.


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Superhighways–Have they done more harm than good?

To make new urbanism work on a wider scale, SanFrancisco-based Calthorpe Associates promotesurban growth boundaries and future developmentaround regional transit. But localities are afraid theywill lose control, so most States have not authorizedregional governance, says Peter A. Calthorpe. Theresult is “fractured development, no regional transit,and no attention to broader environmental andeconomic issues,” he says.

There are many proposed new urbanism projects, butless than a dozen are built. Most, not yet 5 years old,have yet to reach build-out. The more well known areDPZ’s Kentlands in Gaithersburg, MD; architect-planner Calthorpe’s Laguna West in Sacramento;architect Looney Hicks Kiss’ Harbor Town inMemphis; and DPZ’s Seaside, a northern Floridavacation-home town.

Retrofits are possible, but more difficult. Subdivi-sions, with multiple landowners and streets that arenearly impossible to link, are the most troublesome.Office park and shopping center makeovers, such asMashpee Commons on Cape Cod, are easier becausethe cost of a parking garage to free up surface lotspace for development can often be financiallyjustified, says Duany.

The optimal new urbanism unit is 160 acres. Typi-cally, the developer provides the infrastructure. Thetown architect establishes and oversees the plan anddesigns some structures. But other architects are

Until new urbanism becomesmainstream, the approvals processfor each community tends to betortuous and therefore expensive.“The thing that must change is thecost of establishing new communi-ties,” says Daniel L. Slone, a lawyerwith Haymount’s counsel, McGuireWoods Battle & Boothe, Richmond.“It will take the cooperation andleadership of planners, politicians,and environmental and socialactivists.”

Approvals are complicated. Theapproach “raises hundreds of land-use questions” that must beanswered, says Michael A. Finchum,who as Caroline County’s director of planning andcommunity development, Bowling Green, VA, isinvolved with Haymount.

“Anything new is of concern,” especially to lendersand marketers, agrees Douglas J. Gardner, projectmanager for developer McGuire Thomas Partners’Playa Vista, a new urbanism infill plan sited at an oldairstrip in Los Angeles (ENR, 10/04/93, p. 21). ButGardner sees planning obstacles as surmountableand blames Playa Vista’s 5-year approval time on atrend toward a “more rigorous regulatory framework”for all types of developments.

FabricNew urbanism combines aspects of 18th and 19thcentury American and European towns with modernconsiderations, including the car. As in LoudounCounty, the model can be applied on any scale — toa city, a village, or even a hamlet. In West PalmBeach, FL, which is drafting a new urbanist down-town plan, it is superimposed on an existing urbanfabric. Though most of the architecture so far hasbeen traditional, any vernacular is possible.

Like a bubble diagram, neighborhoods shouldoverlap at their edges to form larger developed areas,interconnected by streets, public transit, and bicycleand footpaths. Regional mass transit and superhigh-ways enable workers to commute to remote jobcenters.


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also involved. Public buildings and space, includinga community green, are located near the center, as aremany commercial buildings.

MixUnder new urbanism, there is often no minimumbuilding setback. Lot widths are typically multiplesof 16 feet, and are 100 feet deep. There are a varietyof residential buildings–apartment buildings, rowhouses, and detached houses–usually mixed withbusinesses. Finally, there are alleys lined by garagesand secondary buildings, such as carriage housesand studios.

All elements are planned around “the distance theaverage person will walk before thinking aboutgetting in the car,” says Michael D. Watkins,Kentlands’ town architect in DPZ’s Gaithersburgoffice. That’s a maximum 5-minute walk–a quartermile or 1,350 feet-from a town center to its edges.

New urbanists maintain that a family will need fewercars. Duany likes to point out that it costs anaverage of $5,500 per year to support each car, theequivalent of the annual payment on a $55,000mortgage.

Sidewalks are usually 5 feetwide instead of 4. Streets,designed to entice, notintimidate, walkers, aretypically laid out in a hierarchi-cal, modified grid pattern. Thebroadest are 36 feet wide; thenarrowest, 20 feet. On-streetparking is encouraged andcounted toward minimumrequirements. Vehicle speed is15 to 20 mph, not 25 to 30 mph.Curb return radii are minimizedso that a pedestrian crossing isnot daunting. Superhighwaysare relegated to the far out-skirts of town.

In a grid, traffic is designed tomove more slowly, but it is alsomore evenly distributed sothere are fewer and shorter

duration jams, says Duany. In the typical suburb,broad commercial streets, called collectors, havebecome wall-to-wall traffic, while loop and cul-de-sacasphalt typically remains under-used.

Berkus objects to the grid, except to organize thetown center. The “edges should be organic” forthose who perceive “enclaves” as safer and moresecure places to live, he says.

Bernardo Fort-Brescia, principal of the Miami-basedArquitectonica, also thinks the undulating street andcul-de-sac should be offered. “There are no abso-lutes,” he says.

The firm’s plan for Meerhoven, a new town proposedfor Holland, reflects many new urbanist concepts in amodern vernacular. “Nothing is faked to appear old,”says Fort-Brescia. Every element has a functionbased on modern lifestyles. For example, the townlake is sized for triathlon swimming and perimetermarathon runs. But pedestrians and bikers areencouraged. And mass transit will whisk commutersto jobs elsewhere.

Arquitectonica is fortunate–there are no intractablestandards in the way of its plan. But in the UnitedStates, new urbanists say their biggest roadblocks

ENR, May 9, 1994.


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Retrofits are difficult, say new urbanists. Shopping centers are simplest becauseparking garages can replace surface lots. Mashpee Commons before and after.(Photo and caption, ENR, May 9, 1994.)

are existing street designstandards geared to trafficvolume and efficientmovement, and zoning thatprohibits small lots andmixing building types. Forexample, firefighters andsanitation officials want tohave a street wide enoughfor trucks to turn cornerswithout crossing thecenterline.

“Public works will view yourproposal with suspicion”because in new urbanism,traffic is no longer thedriving force behind streetdesign, says FrankSpielberg, president of trafficengineer SG Associates Inc.,Annandale, VA.

Spielberg, sympathetic to new urbanism, but cautiousabout traffic issues, says there are still questions:Lower expected traffic volume justifies narrowstreets, but is actual traffic volume lower? How longwould it take to convince residents they need fewercars? Will traffic be retained within the project,which would relieve the developer of adjacent roadupgrades?

Traffic engineers have been workingfor 40 years to accommodate theproposals of architects and planners,maintains Spielberg, chairman of theWashington-based Institute ofTransportation Engineers’(ITE) 5-year-old committee on trafficengineering for neo-traditionaldevelopment. Now that the ap-proach is changing, “trafficengineers will respond,” he says.

Reform“Surprisingly, traffic engineers, themost recalcitrant of all, are the first toreform,” agrees Duany. ITE plans topublish neo-traditional street designguidelines late this year or early in1995.

In addition to ITE’s manual,which already contains residen-tial street guidelines, there areAmerican Association of StateHighway and TransportationOfficials standards. Theysupport compact projects, “butonly if you already know whereto look,” says C.E. Chellman,CEO of White Mountain SurveyCo., a land surveyor-engineer inOssippe, NH, and editor ofITE’s draft guidelines.

Chellman says transportationofficials often forget that ITEand AASHTO standards are notbinding codes. Officials arereluctant to use judgment, hesays.

Some engineers simply take issue with the specificsdriving new urbanism. Skokie, IL-based trafficengineer Paul C. Box, who wrote the existing ITEresidential street guidelines, claims lowering thespeed limit is against human nature. He says on-street parking is dangerous because children get hitrunning out between parked cars. He is againstnarrower through streets and the bicycle as transpor-

25’ Curb ReturnRadius2-10’ TravelLanes withParking Lane

10’ Curb ReturnRadius2-10’ TravelLanes with 7’ParkingLane

25’ Curb ReturnRadius2-10’ TravelLanes with 7’Parking Laneplus “Bump-out”

Effects of curb return radii on pedestrian crossingdistance. Source: Wilmapco, Mobility-FriendlyDesign Standards, Wilmington Area PlanningCouncil, Nov. 1997.


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tation unless separate bike paths or lanes areconstructed, which he says is too costly. He alsothinks undulating sidewalks are safer than thosealong the street.

Until there is a body of research to support it,mainstream lenders and commercial interests willcontinue to shy away from new urbanism, says JamesConstantine, principal of Community PlanningResearch Inc., Princeton, NJ. In February,Constantine released data from a survey of “active”home-buyers attending the Home Builders Associa-tion of Memphis show at Harbor Town lastSeptember. Of 123, “a whopping two-thirds” saidthey’d “like” to live in a neo-traditional neighbor-hood, he says. The only market resistance was tosmall lots and minimal setbacks, he adds.

John H. Schleimer, president of Market Perspectives,Carmichael, CA, says even home-buyers surveyedrecently who bought elsewhere “like” the idea ofcommunity and the option of walking places. Butmany said they paid the same price for bigger homeson larger lots.

Haymount’s Clark isn’t rattled: “Someone who wantsto live on a mansion-size lot and ‘commit cul-de-side’has to go elsewhere. That’s why there is vanilla andchocolate.”

By Nadine M. Post

6.3 Street Design forTraditional NeighborhoodsNeo-traditional neighborhoods have begun to appealboth to community designers and home-buyers alike.It is important, however, to consider that neo-traditional street design fundamentally differs fromstandard suburban street design. In recent years,many neighborhoods have been built across thecountry that claim to be neo-traditional that are, infact, missing critical features.The magazine article in this section provides a goodoverview of the concepts of neo-traditional neighbor-hood design. This section provides more specificdetails on neo-traditional street design, and explainshow it is different from standard suburban streetdesign.

Basic Street LayoutStandard suburban street design is characterized by ahierarchical, tree-like pattern that proceeds from cul-de-sacs and local streets to collectors to widearterials. The organization of the network collectsand channels trips to higher capacity facilities. Theuse of streets in residential areas for inter-communityand through-traffic is minimized by limiting access byconstructing few perimeter intersections, reducinginterconnections between streets, and by usingcurving streets and cul-de-sacs in the development.Where this layout is successfully designed andconstructed, automobiles are the most convenientchoice for short, as well as long, trips. The street

layout forces longer, less direct autotravel when street connections aremissing.

The hierarchical street layout reflectsthe guiding principle that streets onwhich residences front should servethe least traffic possible. At best,only vehicles traveling to or from thehomes on a given street would everappear on that street. There wouldbe little or no “through-traffic,”hence the prevalence of cul-de-sacs.Traffic from residential streets isquickly channeled through the streethierarchy to collectors and then toarterials. Only arterials, fronted

Typical suburban neighborhoods offer few route choices for trips.


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primarily by stores, offices, orapartments, provide direct connec-tivity between land uses and otherneighborhoods.

By contrast, Neo-TraditionalNeighborhood Design (NTND) callsfor an interconnected network ofstreets and sidewalks to dispersevehicular trips and to make human-powered modes of travel (such aswalking and biking) practical, safe,and attractive for short trips.Motorists, pedestrians, and publicofficials will find the regular patternmore understandable.

The street pattern in an NTND canalso have a hierarchy, with some roadways designedto carry greater traffic volumes. A basic assumptionof NTND planning, however, is that neighborhoodstreets that serve local residential trips can alsosafely serve other neighborhood trips and somethrough-traffic. For example, a street with 40 homeswould need to carry about 20 vehicle trips during thepeak hour. The effective capacity of this street couldeasily be 200 vehicles per hour without a significanteffect on safety or environmental quality. By limitingthe access to the street as in standard suburbandesign, 90 percent of its effective capacity is wasted.Nearby arterials must make up the difference.

By eliminating dead ends and designing all streets tobe interconnected, neo-traditional neighborhoodsprovide multiple route choices for trips. By usingnarrow streets and by constructing more of them,more, yet smaller, intersections are created. Inconcept, therefore, overall network capacity isincreased, traffic is dispersed, and congestion isreduced in neo-traditional communities. While thisrationale seems intuitively correct, it must becarefully applied. Land use and density are notconstant across a neo-traditional community. Largertraffic generators will attract larger numbers ofvehicles that may require multi-lane streets andintersections.

Use of AlleysPlanners discourage alleys in standard suburbanresidential areas. In a typical suburban develop-ment, an alley behind homes serves no functionbecause garages and their driveways are accessedfrom the street.

However, in Neo-Traditional Neighborhood Design,alleys give neighborhood planners design flexibilityby permitting narrow lots with fewer driveways onlocal streets. Fewer driveways also mean moreaffordable, smaller home sites and more space for on-street parking, especially if the home-owners use thealleys for their own vehicular access, parking, andutilitarian activities. Alleys provide space forunderground or unattractive overhead utilities whilefreeing streets for trees and other plantings. Alleysalso can be used for trash storage and collection andemergency vehicle access. NTND projects do nothave alleys everywhere, but where they do, trafficsafety may improve. Alleys eliminate residentialdriveways and the need for backing up onto thestreet, which would otherwise occur and is inherentlyunsafe.

Street Design SpeedDesign speeds for suburban neighborhood streetsrange from a minimum of 25 or 30 mph to 45 mph. Thedesign speed recognizes the type of facility (local,collector, or arterial), and it allows for a standard 5- or10-mph “margin of safety” above the 85th percentilespeed, which is usually the posted speed. Often, thesigning of wide streets for 25 to 35 mph simplyresults in more speed violations. It is not unusual forneighbors to complain of speeding traffic on neigh-borhood streets and to request actions to slow thetraffic. Stop signs, speed bumps, “Children at Play”signs, and the like may have to be used to slowvehicles from the original design speed of the street.

Neo-traditional neighborhoods have narrower, tree-lined streets.


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Neo-Traditional Neighborhood Design projectsattempt to control vehicle speeds through carefuldesign of streets and the streetscape. MinimumNTND street design speeds are 15 to 20 mph. On-street parking, narrow street widths, and specialdesign treatments help induce drivers to stay withinthe speed limits. T-intersections, interesting routeswith lots of pedestrian activity, variable cross-sectiondesigns, rotaries, landscaped medians, flare-outs, andother treatments may be used.

At slower speeds, the frequency of vehicularaccidents may decline, and those that do occur maybe less severe. What is not clear is whether or notthe frequency of pedestrian-vehicle accidents alsodecreases with speed. Indeed, more than 70 percentof all pedestrian traffic collisions occur in locationswhere speeds may be low (NHTSA, 1989). Pedestrianaccident types are often associated with darting outfrom between parked cars, walking along roadways,crossing multi-lane intersections, crossing turn lanes,dashing across intersections, backing-up vehicles,ice cream vending trucks, and bus stops.

For NTND projects, the goal is to create more“active” streetscapes, involving more of the factorsthat slow drivers. These include parked cars; narrowstreet width; and eye contact between pedestrians,bicyclists, and drivers. The overall impact of theseelements of design is enhancement of the mutualawareness of drivers and pedestrians. Thus, manyprofessionals believe that in a neo-traditional

neighborhood, drivers are more likelyto expect pedestrians and avoid themin emergency situations.

Street WidthIn suburban neighborhoods, streettype, width, and design speed arebased on projected vehicle volumesand types. The larger the vehiclepermitted on the street according tolocal regulations, the wider thestreet. The focus is on motorizedvehicles, often to the exclusion ofpedestrians, other transportationmodes such as bicycles, and otherconsiderations of the communityenvironment.

Ideal suburban lane widths per direction are 12 feet,while exclusive turn lanes may be 10 feet or less.Depending on whether or not parking is permitted,two-lane local street widths vary from 22 to 36 feet,while two-lane collector streets vary from 36 to 40feet. In many suburban jurisdictions, the minimumstreet width must accommodate cars parked on bothsides, an emergency vehicle with its outriggers, andone open travel lane. These “possible uses” insteadof “reasonably expected uses” lead to a worst-casedesign scenario, an excessively wide street, andprobable higher travel speeds.

In contrast to suburban street design, the width ofNTND streets is determined by the projectedvolumes and types of all the users of the street,including pedestrians. The actual users of the streetand their frequency of use help determine streetwidth. In addition, NTND-type standards come intoplay. The basic residential NTND street has twolanes, one for each direction, and space for parkingon at least one side. The resulting minimum widthmay be as narrow as 28 to 30 feet. Design consider-ations, however, may preclude parking in some areas,perhaps to provide space for bicyclists.

If neo-traditional communities encourage narrowerstreets with parking, then vehicles will naturally slowand stop for parking maneuvers and for largerapproaching or turning vehicles that may encroachon the other lane. The NTND concept is that driversmust be more watchful (as they usually are in central

Neo-traditional neighborhoods re-create commercial densities reminiscent to pre-World War II era downtowns.


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business district (CBD) areas) and, once morewatchful, drivers expect to and do stop more fre-quently.

To alert drivers to the relative change in importancebetween vehicles and pedestrians, they must bewarned at entrances to the NTND. This warning mustbe more than signs. Narrower streets; buildingscloser to the street; parked cars; smaller signs;andthe generally smaller, much greater visual detail of apedestrian-scale streetscape all serve as good noticeto the visitor.

Curb RadiiCurb radii in suburban neighborhoods matchexpected vehicle type, turning radius, and speed tohelp ensure in-lane turning movements if possible. Inorder to accommodate the right-hand turningmovements of a tractor trailer (WB 40) and largervehicles, no matter what their frequency of streetuse, suburban streets typically have minimumintersection curb radii of 25 to 35 feet. Some jurisdic-tions require 50 feet or more. What such large curbradii do for smaller, more predominant vehicles is toencourage rolling stops and higher turning speeds.These conditions increase the hazards for crossingpedestrians. The large curb radii effectively increasethe width of the street, the pedestrian crossing time,and the exposure of pedestrians to vehicles.

NTND curb radii are usually in the range of 10 to 15feet. They depend on the types of vehicles that mostoften use the street, not the largest expected vehicle.The impacts on pedestrians, parkingspaces, and turning space for largervehicles are also considered. Thesmaller the curb radii, the lessexposure a crossing pedestrian has.Furthermore, an additional parkingspace or two may extend toward theintersection with small curb radii, orif parking is prohibited, additionalroom for turning vehicles is created.

Intersection GeometryMany manuals detail conventionalintersection design and analysis forsuburban developments (AASHTO,1990). Such intersections aredesigned for an environment in

which the automobile is dominant. Hence, trafficengineers attempt to maximize intersection capacity,vehicle speed, and safety. They also aim to minimizevehicle delay and construction cost. As a result ofthe hierarchical approach to street system design,which carries traffic from narrow local streets tolarger collectors and arterials, intersection size andcomplexity grow with the streets they serve. Driversof these streets expect an ordered structure and anyanomalous designs present safety problems.

In Neo-Traditional Neighborhood Design, theconcept of connected patterns of narrow, well-designed streets is intended to improve communityaccess in spite of low design speeds. The numerousstreets provide more route choices to destinationsand tend to disperse traffic. In concept, the morenumerous, smaller streets also mean smaller, morenumerous, less congested intersections. Again, dueto slower vehicular speeds, greater driver awareness,and the desire for vista terminations, some NTNDintersection designs are typically different fromsuburban designs.

Street Trees and LandscapingSubdivision standards and roadway design practicestrictly control the size and location of street treesand other plantings. Some local regulations may evenprohibit trees and other plantings near the street.These guidelines originated with the precedent of the“forgiving roadway” that arose through tort actions.They generally place trees far from the edge of high-speed roads to reduce the chance of serious

Trees and landscaping form an essential element of the streetscape in NTND projects.


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accidents if vehicles swerve off the road. Forsuburban streets with lower design speeds and spacefor parked cars, trees can be closer to the street.

Trees and landscaping form an essential element ofthe streetscape in NTND projects. The relationship ofvertical height to horizontal width of the street is animportant part of creating a properly configuredspace or “outdoor room.” On some streets thatfeature single-family housing, the design may call forsetting the houses back somewhat from the street. Inneighborhoods and along streets such as this, thetrees form an important part of that street. Whileproviding shade and lowering street and sidewalktemperatures, they create a sense of closure in avertical plane. Along streets that containtownhouses and stores with apartments above them,actual full-sized trees become less important, whilesmaller trees and landscaping remain essentialelements.

Street LightingSuburban neighborhood design calls for large,efficient luminaires on high poles spaced at relativelylarge distances. Their purpose is not only to illumi-nate the nighttime street for safer vehicle operation,but also to improve pedestrian and neighborhoodsecurity.

Street lighting in traditional neighborhoods servesthe same purposes as that in suburban neighbor-hoods. However, the intensity and location of the

lights are on a more pedestrian scale. Smaller, lessintense lumninaires are often less obtrusive toadjacent properties and allow the nighttime sky to beseen. They only illuminate the streetscape asintended.

Sidewalk Width and LocationSidewalks in suburban neighborhoods typically havea minimum width of four feet. While they may lieparallel to the street, they may also meander withinthe right-of-way or lie entirely outside of it.

NTND designers try to keep walking as convenientas possible, and this results in shorter distanceswhen sidewalks remain parallel to the street. Thefocus is on a safe and pleasant walking experience.The typical minimum sidewalk width is 5 feet becausethis distance allows two pedestrians to comfortablywalk side-by-side. Walking distances should be keptas short as possible, and, in traditional neighbor-hoods, horizontally meandering or verticallyundulating designs are avoided even though thesefeatures may add interest. Neither should a pedes-trian route be perceived as longer than the samedriving route, nor should it create undue mobilityproblems for visually impaired pedestrians or peoplewho use wheelchairs.

Building SetbacksConventional front setbacks are 15 feet or more forseveral reasons. Setbacks allow road wideningwithout having to take a building and compensating

its owner. They help sunlight reachbuildings and air to circulate. Inaddition, side and rear setbacksafford access by public safetyofficials.

Traditional designs have no mini-mum setback and, indeed, maximumsmay be specified by some policy-makers. The goal is to integrateresidential activity and street activityand, for example, to allow theopportunity for passers-by to greetneighbors on their front porches.Furthermore, the walls of nearbybuildings help to vertically frame thestreet, an important aestheticdimension.

Pedestrian push buttons should be conveniently placed. Be sure existing site featuresare not obstacles to reaching the button.


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NTND projects are intensely plannedand closely regulated as to types andranges of use and location. Suchplanning affords the otherwise unusualopportunity to have a good degree ofunderstanding about the future trafficdemands for a street, and to design forthose needs. Furthermore, to minimizethe need for future widening, NTNDstreets have adequate rights-of-way,typically not too dissimilar to “standard”requirements, and the buildings do notencroach on the right-of-way. Within theright-of-way, the typical NTND streetwill have a planting strip of 6 feet or soon each side, and parking lanes on bothsides of the street (sometimes striped,sometimes unstriped), both of which provideopportunities for some widening without a great dealof effort if a future wider street is needed.

ParkingThe importance of parking for suburban projectscannot be over-emphasized because nearly all tripsare by car. Off-street parking is preferred; indeed,large parking lots immediately adjacent to the streetgive a certain status to retail and commercial estab-lishments. Sometimes, suburban parking is allowedon the street in front of smaller stores. Because of theimportance of vehicle access in suburban develop-ment, city ordinances typically establish minimumparking criteria.

Neo-traditional design encourages on-street parkingby counting the spaces toward maximum parkingspace requirements. The parking is usually no morethan one layer deep. If the adjacent developmentcontains residential and other uses, parallel parkingis recommended. In commercial areas, 90-degreehead-in and diagonal parking are permitted. Parkinglots are usually built behind stores. As a result, thestreet front is not interrupted by a broad parkingarea.

On-street parking is a concern for some trafficengineers. The concern is that “dart-out” accidents(where pedestrians, especially children, dart-out frombetween parked vehicles into the traffic stream) willincrease if on-street parking is encouraged. Theproponents of NTND projects argue that a row ofparked vehicles enhances pedestrian activity bycreating a buffer between pedestrians and moving

Suburban parking lots in retail developments are vast–and are rarely full.

traffic, that the overall street design slows movingtraffic so that any accidents that do occur are lesssevere, and that the active streetscape makes driversmore alert to pedestrians. There is also some evi-dence that children in conventional neighborhoodsare susceptible to driveway backing accidents. On-street parking, therefore, must be limited to streetswhere the design fosters low speeds (20 mph or less)for moving traffic.

6.4 ReferencesText and graphics for this lesson were taken from thefollowing sources:

Institute of Transportation Engineers, Neo-Tradi-tional Neighborhood Street Design, 1995.

Nadine M. Post, “Putting Brakes on SuburbanSprawl,” Engineering News Record, May 9, 1994, pp.32-39.

Wilmington (DE) Area Planning Council, WilmapcoMobility-Friendly Design Standards, Nov. 1997.

For more information on this topic, refer to:

Office of Transportation Engineering and Develop-ment, Pedestrian Design Guidelines Notebook,Portland, OR, 1997.

“Made to Measure: How to Design a Livable Streetthe New England Way,” Planning Magazine, June1996.

Town of Cornelius, NC, Land Development Code,Traditional Neighborhood District, 1996.


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Cycle 06