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HomeMy WebLinkAbout02/20/1996, 2 - THE TC LTMNG AGENDA DATE A-k -96 ITEM # '2 The Neighborhood Traffic Mitigation Working Grou tools,rather than recommending only two or three,as justify the inclusion of multiple tools: • Boulder's neighborhoods are not all the sat system with alleys. Some neighborhoods were planned with wide straight streets. Others have wide and curving streets. Some neighborhood streets are 20 feet wide and others are 40 feet wide. Because of the variety in Boulder's street designs, different tools will be needed to address differing traffic conditions. • Boulder does not have a true 'arterial' system, with wide, four-lane roads at half mile intervals that effectively move high volumes of traffic. Originally a town;Boulder was not really designed as a city. The city evolved. Consequently, most of our streets, even high volume streets, are lined with homes. Most cities do not do "neighborhood traffic mitigation" on such streets. Our intention is to include any two lane, primarily residential street in our program, therefore tools for many kinds of traffic conditions are addressed. • Boulder's neighborhood's have different characters. A traffic circle may be aesthetically pleasing and appropriate for one neighborhood but ugly or ineffective in another. The NTMP Working Group has analyzed many common traffic mitigation tools (and even some uncommon ones). This 'tool box'should not eliminate other possible tools and ideas. Additionally, these tools may be used in combination. Because Boulder's neighborhoods are unique,the solutions to their traffic problems will probably be unique. The following tool classifications and 'road maps' should make it easier for neighborhoods to determine which tools are appropriate for their street(s). 27 TOOLS BY CLASS/F/Ca nom ARIGHT REDUCE ACCIDENTS: z u • Traffic Circles • Education • Channelization • All Barriers & Diverters • Stop Signs (However, most stop • Stop signs signs that will reduce accidents • Speed Humps have already been installed.). • Semi-Diverters • One way Streets • Street Closures • Drop off zones for schools • Turn Prohibitions • Any tool that reduces speed and/or volume. M/GHT INCREASE SAFETY g 3 s> s FOR>PEDESTRIANS A'ND/OR MIGHT REDUCE'SPEED:5� _w CYCLISTS.' Mfr, • 410 Drop off Zone at Schools • Deviations • Traversable Barrier • Lane Narrowing • Forced Turn Barrier • Traffic Circle • Diagonal Divertor • Traditional Enforcement • Photographic Radar • Raised Crosswalks • Lane Eliminating Chokers • "Sideians" • Chokers/Neckdowns • Speed Humps • Raised Crosswalks • Realigned Intersections • Raised Intersections • . Raised Intersections • "Sideians" • Photographic Radar • Medians • Chokers (all types) • Traffic Lights • Deviations • Barriers • Psyscho Perception • Street Closure 28 TDOLS RSI NKEo By cost y E;.E,� � wx LES$�THAN$1,000 �° � ' BETWEENs$1;000 AND:;$10 QQO • Education • Semi-Diverters with Non-Irrigated • Neighborhood Speed Watch Landscaping • Stop Signs • Raised Crosswalks (no drainage) • Speed Limit Signs • Speed Humps • Turn Prohibition Signs • Street Closures • One Way Streets • Non-Irrigated Traversable Barriers • Transverse Markings • Neighborhood Identification • Crosswalks Median • Creative Signs • Rumble Strips g' ,J J ..& x f.a,;.irw.-d x a,iP x r-y'as..e.},+ 3 , yef% •3r a k`n�F �",p�H$^ j ,&.,d' .� F x. 0000$ $4 , sGREATDJERsTIiAN$40,000 `' _ q ^�.'=':.'ta✓+ • Lane narrowing • Deviations with irrigated • Non-irrigated Deviations landscaping • Neckdowns • Deviations with brick landscaping • Semi-Diverters with Irrigated • Any type of realigned intersection Landscaping • Any type of raised intersection • Semi-Diverters with Brick • Irrigated Traffic Circle Landscaping • Any type of Median • Non-Irrigated Traffic Circle • Irrigated Median Barriers • Non-Irrigated Median Barriers • Brick Landscaped Median Barriers • Forced Turn Channelization • Any type of Diagonal Diverter • Irrigated Traversable Barriers • Turning streets into cul-de-sacs • Brick Landscaped Traversable Barriers 29 Tom SYMBOLS EXPLAINED Fly Tools are marked with 1 to 4 dollar signs, depending on their cost. A single $ indicates the tool is relatively inexpensive to install. $$$$ indicates one of the most expensive tools. Cost effectiveness of projects will be considered. Neighborhoods that want to use very expensive tools may have to contribute a greater share of the cost of the project. The Fre Department, and other agencies with emergency vehicles, may have problems with this mitigation tool. It is a physical tool that can increase emergency vehicle response time to neighborhoods. Consequently, if a neighborhood wants to use this tool, a Fre Department representative must work with the neighborhood from the begining of the project development process. This is an experimental tool. It has not been used much in Boulder and the Neighborhood Traffic Mitigation Working Group is not 100% sure that it will work in Boulder. This tool can be installed temporarily and removed if it does not work. The Neighborhood Traffic Mitigation Working Group thought this tool . . looked promising, and recommends trying it. Tools may be recommended even though their application may be appropriate only to a limited set of conditions and Boulder neighborhoods. Consideration shoul;d be given to whether your proposed application of theis tool will increase danger to pedestrians. Pedestrian symbol without a circletslash indicates the tool is a pedestrian amenity. Consideration should be given to whether your proposed application of this tool will increase the danger to bicyclists. Bicycle symbol without a circle/slash indicates the tool is a bicycling amenity. 30 T. SPEED LIMIT SIGNS Def— m Signs that inform drivers of the maximum safe driving speed under normal conditions. e SPEED LIMIT 25 Temoorary Best Used/f. Can be tried for six months to test • Don't Use If. effectiveness. Clear need to inform • Neighborhood doesn't drivers of the speed want the °visual pollution". limit. Street T_v_oe. Benefits: Any streets, but may be unnecessary on • Inexpensive. eoatives: many low volume residential streets. Unattractive in neighborhoods. • Does not effect vehicle speed. Consi • Posting of artifically low speed limits will require constant enforcement and breed disrespect for traffic control devices. NEIGHBORHOOD SPEED CONTROL PROGRAM Def— In A neighborhood education process in which neighbors become more aware of the specifics of their speeding problems. Neighborhood representatives are loaned radar guns by the Police -Department, to monitor speed and identify chronic speeders. The City will then send letters to offending drivers calling their attention to their behavior and requesting them to change it. Tem— °-°"m Best Used If. Should be in place for two • Don't Use if.. Neighborhood willingness to • No willingness on the part months or longer in order to participate. gain maximum educational • Most traffic is local traffic. of the neighborhood to benefit • Neighborhood Speed participate. Watch has not yet been attempted. Sheets: Bene its: More likely to be effective on • Can effectively address :e�!tivesl�ives• local streets. trafficproblems that are Not likely to be as effective caused by neighbors. • on non-local traffic. • Can heighten general May make neighbors feel awareness of neighborhood spied°n°by one another. traffic concerns. • Can serve to unify neighborhoods. • Can be a good first step toward building consensus on physical mitigation measures. 7Considerations: n in Neighborhood Speed Watch will be limited to two neighborhoods at a time. use of the radar gun will be provided by the Police Department.ods representatives will be asked to sign an agreement to take proper care of the and to use it only as specified by program guidelines. , s ss v NEIGHBORHOOD IDENTIFICATION ISLAND SIGNOR OBELISK Definition: An island in the center of a street that includes a monument identifying a neighborhood and N \ i� marks the entrance to the i neighborhood or a sign, banner or other structure that helps to communicate a sense of neighborhood identity. �. Temgorarv: Can be temporary but removal i unlikely. J Street Type: Works Best N.• Don't Use/f. Collector street or local street • Neighborhood boundary • neighborhood entrance off of definition is desired. collectors or arterials. Maintenance: Benefits: Negatives: Depends on type of installation. • Alerts drivers that a change in • their driving behavior is being requested. • Helps give neighborhood more of a sense of identity. • Allows neighborhoods creativity and participation in design. Considerations: A neighborhood identification island is an entryway treatment that can be used most effectively in conjunction with other tools, if speed reduction is desired. SPEED HUMPS FDiscomfort tion: humps are wave-shaped P humps in the street. The of the speed hump ines how fast it can be BUMP ed without causing fort to the driver or to the vehicle. fort increases as speed limit increases. iT_ -- --- - - - - w� CUD 1 r_SPee—dhum—ps orary Best Used If. Don't Use if. humps are impractical to • The street has a • The street is on a major on a temporary basis. documented speeding emergency vehicle route Tv • problem, and no reasonable "Soft°approaches have alternative is available. are generally proven ineffective. • Steep grades. considered local street tools. Application on collector streets need to be very carefully evaluated. Maintenance: Benefits: Well constructed humps should • Stows traffic. Few drivers 0 eQ�ives: maintain their shape for several travel over speed humps Can increase voice and air years, however the stri in pollution by the hump P 9 with excessive speed more (however, less negative associated with them must be than once. maintained biennially. • °Self enforcing." impact than a stop sign). • Relatively inexpensive. Considerations: v i� Y RAISED CROSSWALKS Definition: A speed hump designed as a P crossing. 1 Ins I t Temvorarv: Best Used N Don't Use N• No. • High volume of • Important emergency vehicle pedestrians. route. • Vehicle speed is a concern. Street Tvice: Berrefits: Negatives Can be used on medium and • Effective speed control at • Negative impact on emergency low volume streets. the installation. vehicles if on primary • Excellent pedestrian emergency vehicle routes. amenity. t. intfersections ns: eed to negotiate with RTD for acceptance of speed humps, raised crossings and on bus routes. Not immediately implementable on these streets, but expect to be e future. sss - CHOKERS: RAVEL BOTH WAYS Defrnition: Large Iamb chop-shaped I �r►� islands installed at the �I �9 intersection to reduce speed. O C . Two lanes of travel are maintained, but lanes are I narrow. Bike lanes are I maintained outside of the choker, on both sides. O O O — O I� O i Q Temgorary Besf For: , Chokers can be tried on a • Dant Use if.. temporary basis for 6-12 Neighborhood that desires • The street is a snow route. months. significant slowing at an intersection. • Pedestrian safety concern at the intersection. • Bike safety concern at the intersection. Street Tvices Bene/its: Chokers will work best on low to • Straight access for bikes. 0 e now medium volume neighborhood • Crossing distance is Snow removal is streets. complicated, especially in reduced for pedestrians. the bike lanes. • Traffic is slowed at the Maint—enance= intersection, possibly Care needs to be taken by reducing accidents. maintenance to keep snow out of the bike and ped lanes. Considfbike s: • Thenes and choker should be well marked. Thenes should be wide enough for bike trailers. - -0-01 0 TURN PROHIBITIONS FEnterm) nition: sical barriers or signs Right Tum°, "No Left ", "Do Not that prohibit a Particular turning movement. I I I i I Temoorarv' Best Used If: Don't Use If: Can be installed • Significant cut-through traffic. • Neighborhood unwilling to limit experimentally or used • Need to eliminate two way its own access. during limited hours,such conflicts. • No appropriate alternative as rush.hours or school hours. facility. Street Tvices: Benefits: Neaatives: Local streets or major, • Reduces cut-through traffic in May increase trip length due to paired arterials. neighborhoods. revised trip patterns. Considerations: SEMI-DI VERTERS Defirrrftion: Physical blockage of one (Po not enter) direction of traffic at one point on an otherwise two way street. i The open lane of traffic is i signed "One way°, that is, traffic i from the blocked lane is not i allowed to go around the barrier through the open lane. i u i T ern Best Used N• can be tried on a • Don't Use if.• . Neighborhood has cut- • No cut-through traffic. through traffic, and there is • No good alternate route for an appropriate alternative diverted traffic. route for blocked cut- through traffic. Benefitslume streets. • Do not present a significant N eoatJves: 9 Compliance with semi- obstacle to emergency diverters is not ioo%a. vehicles. • May increase trip length for • Good for limiting one-way some residents. cut-through traffic. • Can be designed to provide two-way access for bicycles. E,Q_onZsIderatj0nS-' reduction is desired, fitional tools should be utilized. LANE NARROWING F lly narrowed to feet, expanding landscaped areas, ns, cans", et . onstreet parking, etc. Li M20—rary Best Used If. Don't Use!f. [basis an be tried on a temporary • Excessive speed due • No possibility of eliminating for 6-12 months. primarily to street width. on street parking. • Inadequate right-of-way to do a safe, effective Street Tvices• Benefits: treatment. Appropriate for most street types. • Good for pedestrians due to Negatives: shorter crossing distance. • Can be dangerous for bikes. Maintenance: • Slows traffic without Landscape maintenance. (May seriously affecting need to involve neighborhood emergency vehicle participation) response time. rForlane s: rrowing to slow cars, it helps to include visual distractions, such as bushes,treesarkings, and other psycho perception techiques. e accident potential because opposing vehicle streams are brought closer together. trictions must be installed. Simply restriping streets is not effective. I ' I i I r r I 1 r. Mo I I I I I I I �I I I I Q � d i v PSYCHO-PERCEPTION Definition: Any material or message Placed around or in a street that heightens driver . response or induces the desired behavior. Example is transverse markings (striping)with inconsistent spacing that gives the illusion of increased speed. Novelty signs and use of landscaping are other examples. Street Tvne• Best Used If.• Don't Use If. Can be tried on any type of • Neighborhood desire to • street, althougn not all them. Specific technique has been methods are appropriate to proven dangerous or all streets. ineffective. Maintenance: Benefits: Depends on technique. Low • Neoatives: for signs, higher for Gives the neighborhood an • Most psycho-perception pavement markin s and opportunity to be creative with tools are not likely to be g landscaping. their response to traffic effective in the long run, concerns. due to their dependence on • Can be aesthetically pleasing to novelty. the neighborhood. Cons/deratfons- It is important that psycho-perception tools make driving fast on the street seem less safe, but that they don't actually increase danger. a g. STOP SIGNS Definition: Red hexagonal signs displaying the word "STOP°. Stop signs are used to designate the right of way at intersections. Temaorar . Best-If, Stop signs can be tried on a • Don't Use If: unusually high temporary basis. Before the number of accidents • Steep grades. • signs are installed, the involving right of wa , 0 Insignificant traffic volumes. Objectives for installation should • y Insignificant history of be clearly defined. Atter 6 Significant cross traffic correctable accidents. months, if the goals have been at the intersection. • Need and intention is for speed met and the neighborhood still control. wants the sign(s), the installation can be made permanent. If the objectives have not been adequately met, the signs will be removed. Street Tvoes• Benefits: Stop signs are primarily usea ed at • Very inexpensive. atives• low volume street intersections • If there is a lot of cut- If there is nota significant amount the with high volume streets, or on though traffic, stop signs intersection,rcompliance oss traffic twin all four approaches of an might work as a intersection with relative not be compelled. Cyclists and volumes and/or a significaetq,equal • diversion. pedestrians relying on stop correctable accident histo Insignificant traffic signs can be hurt,and ry volumes. accidents may increase. Maintenance- 0 Excessive use of stop signs Low maintenance. renders them meaningless. • Stop signs don't decrease average speed. • Increase noise and pollution. fbbcie siderations: Most stop signs that are warranted for right-of-way control are already installed. Neighborhoods can consider an appropriate use of stop signs as a possible mitigation tool in limited rcumstances, but widespread installation of stop signs for speed control is ineffective and will not supported. REALIGNED INTERSECTIONS Fen on: with a T intersection e street into a larger street,the realigned I tion interrupts the . w oh the larger curving it into the et. Temcorary Best Used If. Don't Use If: Not feasible as a temporary • Enough traffic to • No level of additional traffic on installation. reprioritize traffic flow. the side street is acceptable. • Low volume street. Benefits: Negatives: • Slows traffic when • Much more expensive than a realignment is significant. stop sign. • May encourage increased traffic volume on the affected side street • If not drastic enough, cyclists and cars may ignore the stop signs at the realigned pTConsreatmeniderations: intersection. t is very expensive and probably the most appropriate tool only in rare conditions. �:. C DIAGONAL DIVERTERS Definition: A barrier placed diagonally across a four legged intersection, interrupting 8 traffic flow across the intersection. These barriers can be used to create a � maze-like effect in a I : neighborhood. r I I I I -I I I � I I Tem— ao–rar: Best Used When,• Can be tried on a temporary Cut-through traffic is the D on basis for 6-12 months. primary problem for the• No reasonable akemot neighborhood. routes available for bothh emergency response vehicles and through traffic. • Cut-through traffic is not a significant issue. StreeLTVeS• Benellts. A . Neighborhood(local)streets. • Practically eliminates cut- eoatives• People can tum at higher through traffic. speeds because there is no • Maintains continuous unless • opposing traffic. routing opportunities ( May reduce emergency a cul-de-sac or street routing closure). • 9 Opportunities. May increase trip length for some ome residents. • These barriers should be traversable for bikes and pedestrians. • Likely to increase traffic on adjacent streets, so should be considered only where appropriate alternatives are available. STREET CLOSURE Definition: Street closed to motor vehicles using planters, bollards, or barriers, etc. Pedestrian and bike access maintained. TLLL1 t-------- C, ------- r Q23 Oil s Mao—rare Best Used If. Vaccess. if. - Can be installed • Other mitigation devices, i.e., temporarily. speed humps, diverters would be adjacent neighborhood will Residents of immediate d inadequate. resVicted Street Types Low volume streets where alternative access • Can not substantially, to homes can be adversely impact Provided (i.e.,by alleys) emergency vehicle and a clearly more response time. desirable and feasible • Boulder's 1989 route exists. Transporatation Master Plan opposes street closure unless extraordinary circumstances exist. • Conversion of street from Public to private requires legal action; may'need to grant easements for utilities, municipal services,etc. Benefits: Negatives: • Eliminates cut-through traffic. • May be perceived as Maintenance: inconvenience by some Landscaping. neighbors and an unwarranted restriction by general public. EConsidieration:ge percentage of immediate neighborhood must want it. Adjacent neighborhoods must be g to accept diverted traffic. .- . Bike andt Ne borhood Speed a ch Radar Trailer Neighborh000d rr r':'�• } EVENx- �:P, Identification Islandr t ?: jr �• • r r ��}•.r r r �.r}•}?:.t:i School Drop Off Zones ?.r rsr yyrr.,�',I :,,`r�..�2`rfr1r f}•;rr f- ...r`C Y r tint; };ri .7 Y,rr,Yrrr�r,�rr�� rr 11 • _ r Adjacent to schools Traffic Circles Raised crosswalk Lane Elm.Chokers Turn Prohibitions Raised Intemaction Traditional Enforcermen S1. Perception Forced Turn Barriers hic r;,, rr{ f f?ii?'{t??�}'�rt???etij - - �. �� }`y'c^•.�,�'vr'.•��,'✓: �}����•�,1�.•.,�. rw.1�{ :yG'C.�t4'.u��S�Eu� a7�K sss LANE NARROWING Definition: A lane physically narrowed to nine to eleven feet,expanding sidewalks and landscaped areas, adding medians, °sideians°, onstreet parking, etc. kPE X Temvorarv: Best Used If. Don?Use If.• Can be tried on a temporary • Excessive speed due • No possibility of eliminating basis for 6-12 months. primarily to street width. on street parking. • Inadequate right-of-way to do a safe, effective Street Twes: Benefits: treatment. Appropriate for most street types. • Good for pedestrians due to Negatives: shorter crossing distance. • Can be dangerous for bikes. Maintenance: • Slows traffic without Landscape maintenance. (May seriously affecting need to involve neighborhood emergency vehicle participation.) response time. Considerations: • For lane narrowing to slow cars, it helps to include visual distractions, such as bushes, trees, transverse markings, and other psycho perception techiques. • May increase accident potential because opposing vehicle streams are brought closer together. 0 Physical restrictions must be installed. Simply restriping streets is not effective. ------- _IC - EED Eb-- ------- ----- Eli Median at center of roadway 1 1 1 D I r I I 1 � s C a� z� Uili + = uqlI I I I I all I I I � Q i RAISED INTERSECTIONS Definition: A raised plateau of roadway where roads intersect. The plateau is generally about 40 I higher than the surrounding I _ streets. I EED I I I I I I �I I I Temnorarv: Best For. Don't Use N: No temporary instal' -dons of • High pedestrian volumes • Critical emergency vehicle raised intersection:-. with significant safety route. concerns. • Significant, excessive vehicle speed. Street Types: Benefits: Negatives: Can be used on high or low • Effective speed reduction, • Expensive. volume streets. better for emergency • Not as good as a flat street vehicles than speed humps. for emergency vehicles. • Aesthetically pleasing if well designed. • Excellent pedestrian safety treatment. Considerations: • Transit concerns will need to be identified and worked through. u PSYCHO-PERCEPTION Definition: Any material or message placed around or in a street that heightens driver response or induces the desired behavior. Example is transverse markings (striping)with inconsistent spacing that gives the illusion of increased speed. Novelty signs and use of landscaping are other examples. I Street Type: Best Used U. Don't Use If. Can be tried on any type of • Neighborhood desire to try • Specific technique has been street, althougn not all them. proven dangerous or methods are appropriate to ineffective. all streets. Maintenance: Benefits: Negatives: Depends on technique. Low • Gives the neighborhood an • Most psycho-perception for signs, higher for opportunity to be creative with tools are not likely to be pavement markings and their response to traffic effective in the long run, landscaping. concerns. due to their dependence on • Can be aesthetically pleasing to novelty. the neighborhood. Considerations: It is important that psycho-perception tools make driving fast on the street seem less safe, but that they don't actually increase danger. TRADITIONAL ENFORCEMENT Definition: Sporadic monitoring of speeding and other �l violations by police. Police officers can come out ' to a neighborhood for short periods of time to issue a 11� tickets. Additionally, police vi. ` - officers can Rtake a neighborhood under their J ! wing",and monitor traffic on a regular basis. El [Enforcement mvorarv: Best Used If. Don?Use M: is always • Excessive speed on a street • Locations where ids porary. and there is an urgent need for physically impossible to pull quick action. vehicles over without • Neighborhood is undertaking a creating a hazard. Speed Watch program, is using the radar trailer or has newly installed mitigation measures. • Neighborhood is in design phase and needs interim assistance. Street Twes: Benefits: Negatives: Enforcement can be • Temporary good public • Effect is not permanent: . performed on any street. relations tool. • Enforcement is anm Logistics make some • Serves to inform public that expensive tool(currently locations problematic or speeding is an undesirable total cost recovery for ineffective. mitigation can be behavior for which there are enforcement does not exist). initiated. consequences. fCons/derations:forcement should be regarded as supplemental to other measures, not the sole solution. forcement should not be considered a permanent form of mitigation. Used as a°quick fix°until ore permanent solutions can be developed and implemented.