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02-07-1995 - Informational Report on Speed HumpsCity of West Covina Memorandum 1 TO: City Manager and City Council. AGENDA FROM: Patrick J! Glover ITEM NO. D'� City Engineer/Public Works Director DATE February 7, 1995 ® PRINTED ON RECYCLED PAPER SUBJECT: INFORMATIONAL REPORT ON SPEED HUMPS SUMMARY: In response to the City Council's request, staff has performed further research on the installation of humps and bumps. Humps are being used by other cities with some success and with some problems. INTRODUCTION Until the 1970's, the effects of motor vehicle traffic on the quality of urban residential environments were largely neglected. Since then, however, a number of converging forces have increasingly brought these effects to the attention of both citizens and local transportation officials. Many local governments are finding themselves under intense pressure to reduce the speed and volume of traffic on neighborhood streets to address both real and perceived safety and quality of life issues. . While neighborhood streets are typically public property, many residents feel an "ownership" of their streets and often vocalize objections of drivers from outside their neighborhood who appear to be speeding or are discourteous. Speed humps were developed with the intent of reducing speeding in residential neighborhood. n It is probably necessary to first distinguish between speed humps as opposed to the more familiar speed bumps. 'A speed hump is dramatically different from a speed bump.' Figure 1 is a cross-section drawing showing two typical speed bumps and a typical speed hump. Speed humps normally have a maximum height of three to four inches with a travel length of approximately 12 feet. Speed bumps commonly used in parking lots and on some private roadways, are generally from three to six inches in height with a length of one to three feet. From an operational stand -point, humps and bumps have critically different impacts on vehicles. Within typical residential speed, humps create a gentle vehicle rocking motion that causes some driver discomfortand results in most vehicles slowing to near .15 mph at the hump and 20-25 mph between properly spaced humps in a system. At higher speeds, a hump jolts the vehicle suspension, its occupants and/or cargo. A speed bump, on the other hand, causes significant driver discomfort at typical residential speeds, and generally results in vehicles slowing to 5 mph or less at the bump. At high speeds, bumps tend to have less overall vehicle impact because non -rigid suspensions will quickly absorb the impact before the vehicle body can react. In general, bicycles, motorcycles, and other vehicles with rigid or near -rigid suspensions are more susceptible to damage and loss of control from humps and bumps than vehicles with flexible .suspensions. However, speed humpsf generally represent a lesser risk to those vehicles than do speed bumps. The Fire Department advises that speed bumps and humps can permanently damage the frame of a fire truck. Speed bumps cause more problems than benefits and are generally discouraged. Speed humps, on the other hand, are being used in a few locations with varied results. Therefore, the remainder of this report will only concern speed humps and not speed bumps. HISTORY Speed humps were originally developed in the early 1970's by the Transportation and Road Research, Laboratory (TRRL) in Great Britain. TRRL tested various hump sizes and shapes and several vehicle types operating over a range of speeds. From this work, the TRRL parabolic profile hump was developed. Since then, speed humps have been tested in Europe, Australia, Canada, New Zealand, United States, and other countries. A growing number of cities in the United States are installing speed humps on minor residential streets. Installations of speed humps began in the United States during 1979. I ' City Manager and City Council February 7, 1995 Page Two HISTORY (continue) A great deal of testing has been done on the effects of road humps. Some cities have adopted a design which is 12 feet in length and 2 5/8 inches to 3 inches in height. The cities that have installed speed humps use designs that are almost identical. However, the accompanying pavement markings and warning signs can be quite different. Staff has attached Figure 2 which illustrates some of the standard speed humps and their associated signs and pavement messages. ANALYSIS There are positive and negative aspects associated with speed humps. The following summarizes these aspects. Pos�t�ve; Negative Traffic diversion to collector and arterial Increased noise levels from jolted streets. suspension systems and from repeated deceleration and acceleration of vehicles Typical drivers will slow when crossing crossing speed humps. humps. Traffic diversion to other nearby residential Few reported claims and no reports of '; streets. large settlements associated with speed humps. Emergency response time increase for police, fire, paramedic, and ambulance. Drivers familiar with effects of speed humps may not slow at all. Immature drivers may actually accelerate when crossing a speed hump for thrills. Inhibits street sweeping at and near the humps. Increases costs if street maintenance requires resurfacing or utility trenches cross the speed hump. Vehicles with relatively rigid suspension systems will experience more discomfort when crossing a speed hump. Small vehicles and vehicles with relatively small wheel. radii such as scooters, bicycles, and motorcycles have an increased probability of loosing control. Driver may off-track or swerve their vehicles to try to get one tire into the gutter and thereby reduce the discomfort. The pavement markings and signs installed with speed humps may be considered an eyesore. City Manager and City February 7, 1995 Page Three ANALYSIS (continue) Staff included 178 Cal; humps. Staff received the cities have policies installed speed humps. rnia cities In a postcard survey regarding. their policies toward speed 17 replies. Table 1 lists the results of this survey. Thirty-four of at allow the installation of speed humps. Thirty-eight cities have seventy-nine cities have not installed speed humps on public streets. The guidelines for the installation of speed humps vary from city to city. However, certain standard requirements appear in most. Specifically, speed humps can only be installed on minor residential streets.f No arterials or collector streets may have, speed humps. The street must have a prima facie speed limit of 25 mph and be 40 feet or less in width curb to curb. Although 34 cities prese speed humps installed. 347. Pasadena has a w, cities have between 15 a have few speed humps i these criteria are that a is between 30 and 35 m segment be at least 1 /4 1 petition be circulated by favor the speed humps a speed humps. In general, the installatii people perceive them as State Department of Tra but has recently designa Transportation had desil had to develop a standai and under what conditio The typical driver will he will accelerate. Ovf noise from vehicles cor common complaint. N it is often the case in pi tracking (gutter running and increased street ma respondents. Liability that have speed humps. If there is a very high lE humps can be of some t have relatively few. Th humps and yet they onli large numbers of speed 65 % of the property ow achieve given the horiz( rly have policies allowing speed humps most have relatively few he only city with numerous speed humps is Pasadena which has :ing list for speed humps and more are installed each year. Only 8 d 49 speed humps. The primary reason that many of the cities that their criteria is somewhat difficult to satisfy. Some example of iot speed study must verify that the Critical Approach Speed (85 %) i, that traffic volumes exceed 2000 or 3000 ADT, that the street ile in length uninterrupted by stop signs and traffic signals, that a he requestor showing that 67 % of the abutting property owners d that the requestor be required to pay for the installation of the of speed humps is becoming more popular with the public. Many i effective traffic control device to reduce vehicle speeds. The )ortation will not designate speed humps as a traffic control device them as a roadway design feature. If the State Department of ted speed humps as a traffic control device, Caltrans would have ,ed design, installation warrants and/or guidelines regarding where they might be installed. luce his speed when crossing the hump but immediately thereafter [1, the prevailing speeds of vehicles are reduced. However, the ntly accelerating and the jolted suspension systems seems to be a )ugh the diversion of vehicles to other streets may not be desirable, tice and is apparently the next greatest concern. Vehicle off - inhibiting street sweeping, lengthening emergency response time enahce are not considered serious problems by the survey icerns are not borne out by the experiences reported from cities vel of neighborhood support and an actual speeding problem, speed -nefit. According to Table 1, most cities that allow speed humps City of Brea was one of the first California cities to install speed have a total of nine. Only the City of Pasadena has a relatively iumps at 347. Although Pasadena policy requires a petition with iers approving of speed humps, that number is probably easy to vital street alignment characteristics of many of Pasadena's streets. 0 City Manager and City Council February 7, 1995 Page Four ANALYSIS (continue) Most of Pasadena's residential streets are aligned in a right angle block grid. The grid pattern provides residential streets that have horizontal alignments along relatively long tangents. Because. it is the topography of the road that influences the prevailing speeds, residential streets with horizontal alignment on long tangents lend themselves to higher prevailing speeds. Higher prevailing speeds along minor residential streets will, increase neighborhood support for speed humps and may increase their efficiency. FISCAL EWPACT There is no fiscal impact if speed humps ;are not installed. If speed humps are used, each speed hump including signs and pavement markings costs approximately $2,000. If the requestor(s) pay for the installation costs, the City will only incur minor costs for stationary and postage for the Traffic Committee to i,'process the survey for each request. CONCLUSION In weighing the advantages and disadvantages of using speed humps as well as the information obtained from 117 other cities; it appears that the use of speed humps is still experimental. The research on speed humps by Caltrans and Los Angeles County is still in progress. Since speed humps are not a recognize traffic control device and not recommended by the Fire Chief, the City should continue with the existing policy of not using humps and bumps as speed control devices. ALTERNATIVE One alternative is to direct staff to develop a demonstration project on speed humps so that the. City candetermine for itself the desire to use. or not use speed humps. Prior to any installation, the proposed demonstration project, including neighborhood input, would be bought back to the City Council for approval. RECOMN ENDATION It is recommended that City Council continue to use the existing policy of not using humps and bumps as speed control devices. . L,g atrick J. 9&or City Engineer/Public Works Director PJG:GW:gc AGENDA:spedhump.agn Attachments i t f 1 3 t �I 1 I� - 25 FT L25 FT 12 FT SPEED BUMPS SPEED HUMP 1 AHDBUMPS BUMP UNDULATION AHEAD 15 15 15 15 MPH MPH MPH MPH TABLE 1 13a ou have a ;; Y Hive ©u installed Y Tf Yes, . _ _. poTiey rega�rdtug ''Speed Humps" Ho�v the instalIat AM ►'speed humps"? are existuig City Yes N4 Yes No Comments Adelanto X X N/A Agoura X } X 16 Uses 2 5/8" Hump Anaheim X X 2 Apple Valley X X N/A Arcadia X X N/A Baldwin Park ` X X N/A Installed humps only in I alleys. Banning I� { X X N/A Bell X X N/A Bellflower X X N/A Berkeley X X 10 Drug traffic area and traffic • problems are two criteria for speed humps. Beverly Hills x X 8 Four streets. Bradbury X X 3 Installed against the recommendation of the City i Engineer. Brawley X X N/A Have not addressed the problem. Brea X i X 9 First city in USA to install speed humps. No particular problems. Buena Park 'i X X N/A Campbell j X X 1 Reduced speed and shifted traffic. Carlsbad '' X X N/A City Council stated that speed humps are undesirable. Carpinteria I X. X N/A Carson X X N/A Council. has rejected such request - usually because of neighborhood objections. Cathedral i X X N/A Cerritos- X X N/A Chino X X N/A Will not consider until approved by Caltrans. Claremont X X 1 Try to stay away from it due to liability. Clovis X X 6 Will send packages regarding speed humps. 1 • Commerce Compton Corona II Coronado Costa, Mesa Culver City Cupertino Desert Hot Springs Diamond Bar Downey Duarte El Cajon Escondido Fontana Fountain Valley Fullerton Garden Grove X X X X W.1 X K1 X N/A Do have a few in City parking facilities. ! X 16 j X 10 Three streets - install 13 years ago. They no longer install them. Council will never do it again. ! X N/A Will not install. unless they become recognize by State Department of Transportation and MUTCD. X 13 Located on three streets. X 4 In mist of demonstration f project. X 7 Speed humps work, but be i careful where you place ! them. . X N/A I X N/A They deny requests for speed i humps. X . N/A They are currently reviewing speed humps. I X N/A i X N/A X N/A X N/A They are considering the ' Modesto approach - i.e.. The requestor pays. j X N/A They are presently reviewing a policy. i X N/A X N/A Have a policy but have been directed not to install humps at this time. Glendale X ! X N/A Grand Terrace X X N/A Lomita X X N/A Los Alamitos X X N/A Los Angeles X i i X 15 Plan to expand to 30 + this year through gas tax money or resident's money. j Lynwood X X N/A Maywood X X N/A i Mission Viejo X X 17 Seven streets - have reduced complaints of speeding. Monrovia X X N/A Montclair 1 X X N/A Montebello X X 12 Monterey Park X X N/A Several requests but none met their criteria. Moorpark X X N/A Moreno Valley X X N/A Morro Bay •i X X N/A Presently investigating installing them on one street. National City X X 20 Installed in pairs. Needles X X N/A Newport Beach X X 10 Program was killed by Council in part because of traffic diversion. Norco X X 3 Controversial - Not recommended by the Traffic Engineer. Oceanside` X . X N/A Ontario X X N/A Discouraged because of liability concerns. Oxnard I X X N/A Palmdale X X N/A Prohibited by Ordinance. Palos Verdes Estate X X N/A 1 Paramount X !„ X 40 Pasadena X '„ X 347 Popular - city has many long straight residential streets. Pismo Beach X X N/A Placentia X + X 8 Very effective if used under right circumstances. Pomona I X X N/A Port Hueneme X X N/A Strongly discourage. Poway, X X 3 11 Rancho Cucamonga X X N/A Policy not to install based on City Attorney's advise. 3 i Rancho Mirage X X N/A i Rancho Palos Verdes X j X N/A Traffic Committee will review speed humps by July 1, 1995. Redlands X j X N/A Redondo Beach X X 1 One location by park does not work and people use it for a crosswalk. Riverside X Ii X 2 Discourage it. Rosemead X X N/A San Bernardino X j X N/A San Buena Ventura X i X N/A San Clemente X X N/A San Fernando X X N/A However, they may develop a policy. San Gabriel X , X N/A San Jacinto X X N/A San Jose X j X 2 Speed humps lower property values. San Juan Capistrano X { i ( X 10 Use a petition format with a , 67 % approval requirement. San Luis Obispo X X 4 Noise problem. Works for speed control. San Marino X X N/A City Council has stated "no speed humps" Santa Ana X j X 7 Santa Barbara X X 6 At 400' O.C. as demonstration project - will be evaluated in future. Santa Fe Springs X X N/A Santa Maria X X N/A Will not install because of liability concerns. Santa Paula X j. X 23 Santee X j X N/A Policy is that they not be installed. Seal Beach X I X N/A Sierra Madre X X N/A Currently reviewing speed humps. Signal Hill X j X N/A Simi Valley. x X 49 Spread over 22 streets. 4 South El Monte X X N/A No one has met the criterion - including. a petition. South Gate I X X N/A South Pasadena X X N/A Stanton. X X N/A Temple City X X N/A Thousand Oaks X j X 12 Torrance X X N/A Tustin I X X N/A Upland X X N/A However, three are existing in alleys. Ventura X X 3 Discourage it after being reviewed. Vernon X X N/A Victorville X X N/A Villa Park j X X N/A Vista X X 1 Four more humps under construction - still need to develop guidelines. Walnut X X N/A Requests have not met requirements. Westminster X X 5 Rarely are approved. Yorba Linda X X 8 Five more speed humps will be installed. Yucaipa X X N/A.