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HomeMy WebLinkAbout1991-06-11; City Council; 11191; APPEAL OF TRAFFIC SAFETY COMMISSION RECOMMENDATIONS REGARDING SPEED REDUCTION MEASURES FOR PONTIAC DRIVEa d at c) a g 5 .rl CI PC a, 24 0 \ cn a AB# 16 1% TITLE: APPEAL OF TRAFFIC SAFETY COMMISSION DEP’ C,Ty MTGm6/1 1/91 DEPT. ENG CITY RECOMMENDED ACTION: RECOMMENDATIONS REGARDING SPEED REDUCTION MEASURES FOR PONTIAC DRIVE The Traffic Safety Commission and staff are recommending that the City Council u a Lo -4 Lo a 0 u m A (d 3 6 :: i? *E! rj a 4 m u $ 5 0 0 a c. uu .r( (d 5 Yi u cc $40 3PI u\ Ll -7-4 00 uu U w .ti w3 uu Cd mrd PC0 sc UM Offl &I -4 a 4cn a7-4 Uh ca 33 01 vcr, sa $4 c) -4 a0 u .. 4 cn --. r-4 r-4 2 0 --. F= 0 a 5 \c) : 5: 0 appeal and uphold the TSC recommendations regarding speeding vehicles or Drive. ITEM EXPLANATION: On May 6, 1991 the Traffic Safety Commission considered the request of reside on Pontiac Drive to implement a measure@) to help reduce the speed of travelling on Pontiac Drive between Victoria Avenue and Elm Avenue. This F Pontiac Drive is approximately 0.5 miles long and has a 25 mile per hour pri be 34 miles per hour at Victoria Avenue and 36 miles per hour at Chestnut Various traffic control devices, including 25 mile per hour speed limit signs, hi previously installed on Pontiac Drive between Victoria Avenue and Elm Ave Exhibit 1 ). Pontiac Drive is a residential collector street 1.2 miles in length, terminating at Elr on the north and Tamarack Avenue on the south. From Victoria Avenue Tamarack Avenue the prima facie speed limit is 35 miles per hour. The 24-hour Daily Traffic volume on Pontiac Drive north of Victoria Avenue obtained from count on April 2, 1991 was 3,024 vehicles. During the past four and one-half ye have been two reported collisions on Pontiac Drive between Victoria Avenue Avenue. Both of these collisions were a result of a hit and run vehicle traveling 01 Drive colliding with a parked vehicle on Pontiac Drive. In their appeal, residents have requested that one or more of the following me: implemented: speed limit, Recent speed surveys by staff found the critical speed (85th perc 1. STOP signs be placed on Pontiac Drive at the intersection o Avenue and also Spokane Way. That a barrier be installed across Pontiac Drive immediately Victoria Avenue. That speed humps be installed on Pontiac Drive between Victori and Spokane Way. A combination of the above. 2. 3. 4. The Traffic Safety Commission evaluated the traffic data collected and also c( testimony by citizens at the meeting. However, a program of residential neigl speed control generally follows a four step process outlined as follows. This prc endorsed by the Traffic Safety Commission, in principle, as evidenced recommendations to help reduce speeding vehicles on Pontiac Drive, 1, Establish and enforce general laws pertaining to speed limits. 9 e q PAGE TWO OF AGENDA BILL NO. 14 /q/ 2. Install traffic control devices to provide regulatory or warning mess the vehicle driver. Educate residents to better understand the causes of problems, pl solutions and the advantages and disadvantages of implementin! solutions. Install geometric design features within the roadway to mana physical movement of vehicles or pedestrians. 3. 4. By a 5-0 vote, the Traffic Safety Commission recommended that the following act implemented on Pontiac Drive. 1. Provide additional visual reinforcement of the 25 mile per hour res speed limit by the following actions: A. Replace the existing 24" x 30" speed limit signs that are loci Pontiac Drive at Victoria Avenue and Olympia Drive with lar! x 45" 25 mile per hour speed limit signs. Install one additional 24" x 30" 25 mile per hour sign i direction on Pontiac Drive in the vicinity of Chestnut Avem Stripe a "25" legend on the pavement adjacent to the new limit signs to be installed. Replace the existing 24" x 30" R2-4 "25 Zone Ahead" sign larger 36l x 45" R2-4 "25 Zone Ahead" sign. B. C. D. 2. Continue to provide police enforcement of speeding vehicles on ' Drive on a manpower available basis. Send a letter, signed by the Police Chief, to all citizens (1 ,OOO+ ho the Pontiac Drive community asking for their cooperation in obsen 25 mile per hour speed limit. Establish a Pontiac Drive neighborhood task force. This task i recommended to include local neighborhood volunteers, hom association representatives, Neighborhood Watch captains ( designated representative, a Police Department Traffic I representative and an Engineering Department Traffic Engineering I representative. The task force would initiate a Neighborhooc Watch Program and begin to evaluate other appropriate control me The task force is to report back to the Commission within three mo its progress. 3. 4. FISCAL IMPACT: Impacts vary depending upon the recommended course of action. 0 a PAGE TWO OF AGENDA BILL NO. L(, /y/ EXHIBITS: 1. Condition Diagram. 2. 3. Minutes for May 6, 1991 Traffic Safety Commission meeting. Appeal letter dated May 12, 1991. DSN / R1 (TYPICAL) LEGEND - STOP SIGN - SPEED LIMIT SIGN R2-4 - 25 ZDNE AHEAD SIGN R26 / 81 - NO PARKING ANYTIME / BIKE LANE SIGN DSN - DOUBLE STREET NAME SIGN DOUBLE YELLOW % (TYP.) R26 / 81 (END) R26 / 81 (BEGIN) BIKE LANE (TYP,) I Date of Meeting: May 6, 1991 Place of Meeting: City Council Chambers COMMISSIONERS CALL TO ORDER: Chairman Fuller called the Meeting to order at 3:OO p.m. ROLL CW: Present: Commissioners Fuller, Blake, Melideo, O'Day and Stachoviak. Absent ! None. Staff Members Present: Bob Johnson, Traffic Engineer Sgt. Don Metcalf, Police Department Lloyd Hubbs, City Engineer APPROVAL OF MINUTES: The Minutes of the Regular Meeting held April 1, 1991, were Fuller approved as presented. Blake Melideo O'Day Stachoviak ORAL COMMUNICATIONS: There were no requests to address the Commission on a non- agenda item. OLD BUSINESS: Bob Johnson reported Council will adopt the prima facie speed for El Camino Real from Lisa Street to the south City limits at tomorrow night's Meeting. NEW BUSINESS: A. Pontiac Drive, Victoria Avenue to Elm Avenue - Request for STOP signs at Victoria and Spokane intersections, installation of speed humps and/or other measures to reduce speeds. Lloyd Hubbs, City Engineer, gave the staff report, stating this item has been before this Commission a number of times, with staff looking at a number of measures to address this speeding issue. This has been an issue for many years, and the request has been made to install STOP signs at Victoria and Spokane and speed bumps and other diversionary types of action to divert traffic. Mr. Hubbs stated that Sgt. Metcalf of the Police Department, Bob German of Risk Management, Brian Watson from the Fire Department, are all present to answer questions. There was a petition mailed to the Commission and included in the staff packet. The request has been made for speed humps--not speed bumps. Transparencies were shown of the area in question and the residences in the area; also tables showing the traffic volumes and a spot speed survey. Council did establish Pontiac as a through street on the recommendation of the Traffic Safety Commission, as it did qualify for that designation. Also, no parking was established on Pontiac to allow for bike lanes. MINUT 8 3 0 y NEW BUSINESS: (Continued) The section to Pontiac being considered today is between Victoria Avenue and Elm Avenue, which is a 0.5 mile portion. There are six intersections, and since 1987, only two collisions have occurred on the street- -one was a hit and run where a parked vehicle was hit with one in 1988 and one in 1989. There have been no collisions at the intersections. Pontiac is a residential collector street, and is built for a capacity of 1,200 to 5,000 ADT. There is no doubt that there is speeding on Pontiac, as on most of the streets of the City. The portion of Pontiac Drive from Victoria Avenue to Elm Avenue qualifies as a residential district with a prima facie speed limit of 25 miles per hour. Signs are posted and legends are striped on the roadway surface. The most recent speed survey was done in January and April at Chestnut, and the critical speed was 36 miles per hour. Sgt. Metcalf stated that with the critical speed at 34 to 36 miles per hour, this is approximately 10 miles over the speed limit. There has been selected enforcement in the City based on accidents. There are ten streets where over 60 percent of the injuries occur. Traffic enforcement in those areas has resulted in a reduction in accidents. Radar is only for the critical speed, or above. Sgt. Metcalf said that on Pontiac, they issued 52 citations, with 48 of them to local residents of that area. There have been only two accidents and Pontiac is not a unique street. Sgt. Metcalf continued, stating that the last three months the Police have focused on Pontiac Drive, and when the Police are present, the speed slows down, but if they leave, within 48 hours the speed returns. Bob Johnson stated that staff had checked license plates to determine whether the speeding was local people or those passing through. When they checked those entering and leaving the area, only abut 15 percent of the traffic was passing through, with the rest being local. Mr. Johnson said that STOP signs to slow traffic are not an unusual request from the public. However, they do not do the job. The warrants are not met for STOP signs at Spokane or Victoria. Several things have been done in this area to help enforce the speed limits, and Mr. Johnson explained what has been done and added that staff is trying to come up with an engineering solution to a residential problem. Mr. Hubbs stated that this is a neighborhood speeding issue and as traffic volumes increase it will become critical in urban areas. Shortcuts are initiated to avoid the traffic, and speeding is a factor similar to other conditions. To address this problem, experimental approaches are being tested. These do open cities to risk and must be done with detailed traffic studies and carefully implemented. a MINUT!! Page 3 y May 6, 1991 COMMISSIONERS NEW BUSINESS: (Continued) Slides were shown of barricades, road closures, raised medians and speed humps in various cities. Mr. Hubbs stated that some of the problems connected with these various types of experimental devices are government liability, noise going over the bumps, emergency vehicles access--particularly ambulances carrying a patient. Also, these devices are expensive to install and are somewhat unsightly. He said he did Pontiac Drive or any other street, without more discussion and research at the Commission level and throughout the community. Mr. Hubbs said staff wants to evaluate this uniformly throughout the City and develop a criteria, and review the legal and risk management aspects. Bob Johnson summarized the recommendations of the Traffic Safety Coordinating Committee and used an overhead to show them. Thomas Johnson, 3624 Pontiac Drive, representing Chestnut Hills Community Action Group, stated the neighbors are concerned about the speeding and their goal is to prevent a traffic fatality. He said the north Pontiac residents are different than those who use this as an access road. There are 44 houses with driveways on Pontiac on north Pontiac and no driveways on south Pontiac. Mr. Johnson showed a transparency of the street layout. He said the north portion is 25 miles per hour with no bike lanes and the south portion is 35 miles per hour with bike lanes. However, nobody drives at the speed limit, and north Pontiac is a shortcut for many people. Mr. Johnson said that safety is the main concern, and the speed must be controlled for safety. He reviewed the recommendations made by staff, and said that a would block the traffic and remove the problem. He added that speed humps did slow the traffic in Thousand Oaks. They want a device installed on the street. Tony Loeffler, 3555 Pontiac, explained about road humps, stating they protect public health, increase road safety and divert unnecessary traffic while retaining normal access and appeal to all users. Oscar Williams, 3429 Pontiac Drive, stated the residents there have a problem and don't know the answer. He asked the engineers and law-enforcing officers to do what they can to get it resolved. Rocky Natale, 3453 Pontiac Drive, stated that 90 percent of the traffic through Pontiac live on the lower end, and something must be done. Anthony Tyler, 3465 Pontiac Drive, stated he can't back out of his driveway because of the speeding. not feel any of these devices could be recommended for solution is needed, not larger signs. A barricade e MI NUT^ y I May 6, 1991 Page 4 COMMISSIONERS NEW BUSINESS: (Continued) Yvonne Stargardt, 3625 Pontiac Drive, stated that before the street was cut through there was no speedinq problem. The speeders are from the south side using their area, and something must be done. Robert Hoskins, 3558 Pontiac, asked for a show of hands of people who have had at least three dangerous incidents backing out of their driveways, and approximately 80 people held up their hands. He said the speeding is dangerous on Pontiac Drive. E. R. Hunter, 3623 Pontiac Drive, stated that a barrier is the ultimate solution. Mike Stevens, 3622 Pontiac Drive, spoke about the speeding and the danger in backing out of driveways. He was in favor of closing the street. Manya Bebieff, 3627 Pontiac, stated she has been writing to the City about the problem on Pontiac Drive since 1988, and has meet with staff. She said that north Pontiac and south Pontiac are different communities and something must be done. She said she favors speed humps or closing the street. Janet Jones, 2613 Banbury Court, stated she had some petitions signed by other neighborhoods that will be impacted if traffic control devices are installed on Pontiac Drive. Unwarranted traffic control devices deny easy access to Elm Avenue and cause inconvenience to anyone going through the area. Anna Vallez, 3621 Pontiac Drive, representing Residents for Pontiac, addressed the Commission in favor of placing a gate on Pontiac, stating then emergency vehicles would have access with no problem. She said that larger signs would not help the situation, and said she would like the number of tickets written by the Police on one day in that area. Rick Wagner, 3608 Pontiac Drive, stated he could not back out of his driveway and was in favor of a barricade at the top of the hill. David Woodward, 3413 Corvallis Street, spoke for safe access to the homes. Chairman Fuller closed the public testimony portion at 4:55 p.m. He asked for a show of hands of those favoring stop signs, speed humps or road closure, and almost all those present responded. The next largest number of people favored closing of the street and smaller numbers favored the stop signs and/or humps. Commissioner Melideo commented that this is a public street, and the people seem to feel it is their private street. She expressed concern about hearing that type of testimony, as it means a division in the neighbors, rather than working together as a community. She said it is the neighbors themselves that are affecting the area by the way they drive, and they must work together to solve the problem. NEW BUSINESS: (Continued) In response to query regarding the speed humps, Lloyd Hubbs stated the City is studying them, but the hope is that it would not be necessary to resort to them. Commissioner O'Day also asked about raising the speed limit, but staff stated that due to the number of residences in that area, it does quality for the 25 m.p.h. speed limit. Staff reiterated that stop signs cause accidents, particularly when they do not meet the warrants. Speeders are the most common complaint on most of the City streets. However, speed humps are not very good- looking. Blocking a street causes problems. Commissioner Stachoviak suggested that maybe this area would be a place to try speed humps, if and when the City decides it is feasible. Chairman Fuller stated he could not approve installing speed humps ahead of criteria being established by the City. He said it is not feasible to close a collector road. The Traffic Safety Commission accepted the Traffic Safety Coordinating Committee recommendation, as follows : 1. Provide additional visual reinforcement of the 25 mile per hour residential speed limit by the following actions: A. Replace the existing 24"x30"' speed limit signs that are located on Pontiac Drive at Victoria Avenue and Olympia Drive with larger, 36"x45" - 25 mile per hour speed limit signs. B. Install one additional 24"x30" - 25 mile per hour sign in each direction on Pontiac Drive in the vicinity of Chestnut Avenue. C. Stripe a 25" legend on the pavement adjacent to the new speed limit signs to be installed. D. Replace the existing 24"x30" R2-4 "225 Zone Ahead" sign with a larger 36"x45" R2-4 "25 Zone Ahead" sign. 2. Continue to provide police enforcement of speeding vehicles on Pontiac Drive on a manpower available basis. 3. Send a letter, signed by the Police Chief, to all citizens (1,000+ homes) of the Pontiac Drive community asking for their cooperation in observing the 25 mile per hour speed limit. COMMISSIONERS Fuller Blake Melideo O'Day Stachoviak MINUTE s 0 May 6, 1991 Page 6 u COMMISSIONERS NEW BUSINESS: (Continued) 4. Establish a Pontiac Drive neighborhood task force. This task force is recommended to include local neighborhood volunteers, homeowner association representatives, Neighborhood Watch captains or their designated representative, a Police Department Traffic Traffic Engineering Division representative. The task force would initiate a Neighborhood Traffic Watch Program and begin to evaluate other appropriate control measures. The task force is to report back to the Commission within three months on its progress. Division representative and an Engineering Department REPORT FROM TRAFFIC SAFETY COMMISSIONERS: Commissioner Melideo inquired about bikes on the sidewalk along the fence on Carlsbad Boulevard, and staff stated bikes are not allowed on any sidewalks in Carlsbad. Sgt. Metcalf stated the Police Department is starting a bike patrol and three officers will be on bicycles by the Memorial Day Weekend from the north City limits to the south in the beach area. Staff was requested to bring the concept on the modified traffic management program to this Commission for discussion. Commissioner Stachoviak stated he felt the Price Club would be a disaster. ADJOURNMENT: By proper motion, the Regular Meeting of May 6, 1991, was adjourned at 5:23 p.m. Respectfully submitted, ww Harriett Babbitt Minutes Clerk ---- . - /f-TT-- eq$,7yf* - 75 May 12, 1991 e City Clerk’s Office City of Carlsbad 1200 Elm Ave Carlsbad Ca, 72008 Re: Pontiac Drive Attention City Clerk; Pursuant to the recent decision by the Carlsbad Traffic Safety Committee on May 6 1391 regarding speed control on Pontiac Drive, we request an appeal of that decision to the City Council. We belive that this proposal is inadequate to reduce speeds 13 MPH. The measures in the proposal are not a permanent solution and the Traffic Department admits that it will have little or no affect on the speeds. Enclosed please find copies of the original request to the Safety Committee. Please notify us as soon as scheduling is COItkpleted at the address given below. - -- ”. -,x ‘7 Chestnut Hil C/o 3555 Pontiac Drive Carlsbad, Ca. 92008 cc Mayor Lewis cc City Council 0 0 March 3, 6331 Traffic Safety Committee C/o Robert T. Johnson, Jr., P.E. City of Carlsbad 2875 Las Palmas Drive Carlsbad Ca. 92009-4859 Dear Mr. Johnson Pursuant to our recent neighborhood meeting with you on 1/22/91 we are presenting the following petition. As the next step in making Pontiac Drive a safer and amicable access for the children and residents in the neighborhood, we request the placement of this petition on the Traffic Safety Committee's agenda. Additionally we request that any studies done for this purpose not affect or alter the studied subject(s) , and accurately reflect typical high volume periods. As you know our own traffic studies show that the 85% speed is 44 MPM, with a maximun of 49 MPH. We feel that the infringement of more than 80X of the traffic on north Pontiac originating from south Pontiac is uncalled-for on this residential street. This neighborhood considers these statistics unacceptable. It is imperative that the city make this residential street and both major intersections, safer for resident pedestrians and young bicyclists. We petition that (1) there be a reduction to the traffic using north Pontiac as a short cut to the north section of El Camino Real, and (2) limit the maximum level of speed to the 'prima facia' speed limit of 25 MPH. We therefore petition that the Traffic Safety 1 'Heisenberg uncertainty principle: (A driver will slow upon sight an uniformed officer or marked car.) 0 0 Committee review the alternatives below, study if necessary and ratify at least one of the main elements. - Installation of STOP signs on Pontiac at the two admittedly blind intersections of Victoria and Spokane. - Installation of a barrier at the division of north and south Pontiac, as you have previously suggested between Victora and halon. - Installation of speed reducer humps' to slow traffic approaching both directions of the Spokane and Victoria intersections. - A combination of the above alternatives. Please notify us upon setting a date and time for this subject. Thank you for your personal attention to this very serious matter. ction Group C/o 3555 Pontiac Drive Carlsbad, Ca. 92008 cc City Attorney cc Mayor Lewis cc City Council cc Chief Vales cc Saftey Committee cc City Manager 2 A new feature to California, documentation is included. 0 0 i --- NAME ADDRESS a 0 0- -.* %d 4 0 0 ADDRESS ---_ NAFlE /em ston&(-* \ (1 hd 01 k .\.\3A- +A%-& m3-L 2775 iSpo-*(L - 7 c*c a717 IJI! &*SY&rnLf @. 72L.r.- s7/,- spo/(a, fweq e+ A- =zhL 4Lk7// 56 / L/.I-j k u - 37 9/ fl4 739 -5325- i loel -3-LTAd 6- F,kkL, ,qJ(lC [& )OyyJnna6 %/ A&\ 3737 c9,.%\,,AT / q7.R - 92y-i 3q37 e ,,e5Sj)bf- 7w-97 7- SL \ \ ---- I e.-wJ 3 &I&A C Nb 3 be/& #G/eu~ ?U ue// 34d4,L,&~0&-7,,~,44& 0 0 v --_ NAME ADDRESS 0 0 NAME ADDRESS e -a Lb 4 ~ -. I L Speed Humps and The'Thsusand Oa Expesier By J. P. Clement, P.E. ecause of the high traffic speeds speed was 37 mph, ranging from 27 to "Sleeping Policeman", a "P e 0 4 bumps were evaluated with sizes rang- iq from2inGheSWide by O.5hCheS high to 12 feet wide by 6 inches high. The British finally settled upon the 12 toot by 4 inch size (3.7 m by 102 mm) as the most ideal shape. In Contrast to speed bumps, it was found that: - '1) At or below the design speed, drivers would suffer no discomfort, and 2) Above the design speed, drivers would suffer increasing levels of dis- comfort depending on the amount that the design speed is exceeded, and 3) Motorists deliberately driving over a hump at excessive speed would most likely be able to retain direc- tional control of their vehicles. It was further anticipated that dramatic speed reductions cou!d be achieved under "real life" conditions because most car drivers reported a "preferred" hump crossing speed of 15 mph. The next logical step for the British was to install these devices on public roadways to determine their actual ef- fxtiveness on their residential roads. Since 1975, 63 speed humps have been installed on 10 streets in 9 com- munities in the United Kingdom. AI- though their residential area speed limit is 30 mph. the test roads were experi- encing prevailing speeds as high as 40 mph and carried as many as 8,600 vehi- cles daily. Previous studies revealed that the over- Figure 2. . The results were extremely success- ful. With the 12' x 4" speed humps spaced from 160 to 51 0 feet apart, the maximum prevailing speeds were re- duced an average of 30% (from 32 mph before to 22 mph after). The actual pre- vailing speeds across the speed humps averaged about 15 rnph for cars and . light vans and about 12 mph for trucks. These devices were also highly SUC- cessful in reducing the volume of un- necessary traffic by discouraging the use of these slreets as short-cuts. Using 16 hour traffic count data (from 0600 to 2200 hours), traffic was reduced an av- erage of 30% (ranging from a low of 1 Yo to a high of 64%). Furthermore, the overwhelming majority of residents (79% average) and non-resident public hearings, the City decided to in- 25 mph prima facie speed limit. motorists (60% average) favored the humps. Most importantly. in an analysis of col- lision statistics at all of these locatipns. the British concluded that "on the whole, humps do reduce accident frequencies, and this reduction is statistically Signifi- cant at the 0.196 level". Based upon the successful results ob- tained in Great Britain. the United States Department af Transportation (via the Federal Highway Administration) spon- sored further real-life installations of speed humps on public roads in two U.S. Cities (kea, California and Boston, ' Massachusetts). The demonstrated continuing real-life success of these 12' x 4" speed humps in these twd cities has led to several other jurisdictions in- stalling these devices on public roads including Sacramento. California; Wash- ington, D.C.; and Thousand Oaks, California. And the list is growing. Thousand Oaks Testing Although we were somewhat skepti- cal at first, our research convinced us that these speed humps were at least laworth a try". it was our hope that we wouid be able to document further real- life experiences with these devices on our public roads. "Seeing" would be be- lieving. On January 22, 1981, such an OppOflUni~ arose. On that date the resi- dents along Kelly Road petitioned the City for help in reducing the traffic speed and traffic volume along their streets. Ke''y Road Kelly Road is a 2,860 foot long, 40 foot wide residential collector road with a straight and gently rolling alignment (vatying from 0.4 to 10.4% in grade). all mean speed was 37 mph. the prevail- ing speed was 43 mph and 99.7% of the motorists exceeded 25 mph. Because the California Speed Trap Law requires that speed limits be posted dose to the prevailing speed of motorists if radar is used on residential streets pver one-half mile of uninterrupted length (2.640 feet and in the abscence of other factors), the speed "should" have been posted at about 45 mph. This office, however, simply could not justify such an "unrea- sonable" speed limit on this residential roadway. The residenfs of Kelly Road had origi- nally petitioned for stop signs andlor bar- ricades to control traffic. However, after several neighborhood meetings and stall the experimental speed humps. To that end, during September of 1981, six 12' x 4" speed humps were installed on Kelly Road at spacings ranging from 440 to 570 feet. The speed humps on these roads were installed at a total Cost Of about $500 each, of which only about 20% is for materials. A 2" x 12" x 14' board was Gut t0 the shape of \he 0 humps and used as a template-: during construction to insure ma shape conformity of the asphalt coat. Toverifythe final height and of the speed humps, elevations taken with a transit along one foo' vals at 6 to 8 locations on one ! representative speed hump. I humps were "string-lined" to dete hump height only. This study ret that if a speed hump is constructec care and in two lifts, the final shap, height can easity be maintained to 1 2% inch tolerances. However, wht humps were installed in only one lit PeciallY on Steep roads, the a height and shape could vary by as I as 1 % inches across a single hump therefore. suggested that such s, humps be placed in two lifts uti1 templates for both lifts to in maximum height and shape confor As can be Seen in Table 1. the ob Prevailing speeds (85th percentile) \ reduced by 30% for a net reduction ( mph (from 43 mph before to 30 after). The prevailing speeds betv the humps and across the humps v reduced to 32 mph and 19 mph res1 tively. The dramatic downward shi the entire speed profile cuwe to! the ideal curve is clearly illustrate Even though speeds were ( matically reduced providing a pos improvement in overall safety, this 01 still had the following "reservations" garding the continued use of the 4-il high speed humps: 1) There is visual evidence that sc vehicle's trailer hitches occasion; bottom out on these humps. 2) The roadway surface about s f downstream of several of the hun has been scarred from an occasio ' . 3ront bumper striking the ground. pick-ups tend to become airborne the prima facie speed of 25 mph. 4) The prevailing 19 rnph hump Cr( sing speed was 6 mph less than ! 5) The prevailing mid-hump speedof ~ mph was still 7 mph over the prir facie speed limit of 25 mph. 6) The acceleration and deceleration vehicles along this road resulted irl speed variance of 13 mph. 7) The preferred hump crossing speei for the fire trucks and buses (1 5 m( and 10 mph respectively) were 10 - 9. -I _. $ . : -5 z * =\ - 1 was placed and rolled hot Over ; - 1 -. * 1 1 1 1 i (- 1 3) Highly popular unladen comp 'c 36 ITE Joumal/Januav 1983 Installed 918 1 3/62 Y82 7/82 Overall 85% Speed Road Length 2860' 2180' 2180' 1580' Before 43 38 38 2 Nominal 4" 3" 3" 3" Change% 30 21 34 i \ Actual 3.5-4.0" 3.2-3.4" 3.0-3.4" Between Humps 27 26 23 < Hump On Humps 14 19 18 1 2' ' Hump Height- . Change # 13 s 13 I Hump Ouanlity 6 3 6 5 After 30 30 25 ~ Hump Height- Mean Speed. Spacing 440-570' 690-800' 250-400' 230420' Speed Change 13 7 5 Volume 4080 1600 1600 790 Between Humps 32 34 27 Before 37 34 34 23 Speed Change 13 10 4 Change # 13 11 14 5 Before 99.7 97 97 24 Hour 85% Overall Mean Speed On Humps 19 24 23 Afler 24 23 20 18 % Exceeding 25 mph Change Ol0 35 32 41 22 After 40.5 35 15 1 i To 15 adequately mph less than address the speed all of limit. these r ;A[,, 'i -" , A.zm , it ' FA-%,< ---, humps. Another opportunity surfaced y-y;;.-;; :.nu . : m- [; f , , ;;.;I, .*,e . .. ; ;ir' -" ; H,. "I \ . -* n,..r.-nC I-*- .. concerns and to bring the prevailing speeds closer to the 25 mph prima facie speed limit would necessarily require as reducing the spacing between the permitting the continuation of this exper- iment when the residents of Silas Av- _- >I w,no f-I nrnl,,& r.i-r. ( lowering the height of the humps as well 15 YIII r-J : '-ro ... :-r, L ... :I: . : .. _. .. ../x. : . -t enue petitioned for speed humps. __..-+ ""..",I" r+-, - JY a~,,# (-1 Silas Avenue Silas Avenue is a 40 foot wide, 2,180 foot long residential street with a refa- 5.996. The prevailing speed of traffic on this roadway was 38 mph with 97% of the motorists exceeding the 25 mph '' r " - " ., " " L ' * speed limit. Initially, three 3 inch high speed humps were installed at 690 and 800 foot spacings. The lesser heights did re- sult in the desired effect with prevailing speeds recorded at 24 mph across the humps. Because of the large spacings between lhe humps. however, mid- hump prevailing speeds were reduced to only 34 mph. In the next phase of this study three additional speed humps were installed with the resulting overall spacings rang- ing from 250 to 400 feet. This closer spacing reduced 'mid.-hump prevailing speeds to 27 mph. Coupled with the further reduced prevailing hump cros- Sing speed Of 23 mph. the speed var- . -\. r-Z. : I . , I:. : . . ..,! ;; ; : \... i, I 1 ',*.,- - .; .L -,: : ..-) ..' ,' ,:,'..\ .\ :*.: i 4.. i I : : , x, '... ' . ",.....I," 1 c . .. n -,e,-, n **/--I) Figure 3. Before 8 Afler Spee Avenue. Thousand Oaks, Catifot tivety flat gradient ranging from 1.6 to : : ,..,,. /:. - ;.:', , '. n: .. t . I _. . ' .. i , i. .. .... , ... . . ..&<.' -1 _______ ... --I . Figure 2. Belore 8 Alter Speeds on Kelly Road. Thousand Oaks. Californra t iance along this roadway was held lo within 22 mph of !he 25 mph speed limit. This dramatic downward shift of the en- tire speed profile is clearly illustrated in Figure 3. Note that the "after" speed profile curves are very nearly identical to the "ideal" speed curve. Figure 4 illustrates the resulting pre- vailing speed profiles for the various size humps studied at various Spacings. It is clear to the author that 3 inch high humps spaced an average Of 300 feet apart represents the most ideal situation for reaiistic speed managem dentlal roads in keeping wit facie speed limit. The same vehicles were t on Silas Avenue and in eve preferred hump crossing creased by 5 mph. No vehic airborne and in all trial run: Datsun 280 ZX at speeds 11 (with "hands off' the stec there was absolutely no stc ,jerk or loss of any direction anytime. (- IT€ Journal'Janu; 35 Cindy Avenue Some concern has been expressed by other agencies relative to the desira- bility of installing speed humps on streets where the grade exceeds 5%. This oftice. however, believed that if 3 inch high humps were used at close sbacings (to maintain prevailing speeds at a low level) grade itself would have a limited impact on whether or not to install these devices. It should be noted that the British installed a 4 inch high hump 301 25-.--- 20 - ,~ /o - 5- \ ;$$' n... /K-l...& 1 - -- - -- - I3 ZY 23 tr IT 17 a a D * D .L ment of the Environment, TRRL SR423.1978. 5. "speed Contrd Humps in Kensington and Gbsgow". R. Sumner & C. Baguley, U.K. Oepart- mnt of the Environment TRRL SR456.1979. \ 'more common place, there will be even ~~l~~~~~~~~"~~.m~~~~~~~ g2 mment. TRRL ~~1017.1981. 7. "State of the Art Report: Residential Traffic Management... o, Smith 8 D. Appleyard, u.s.D.o.T., ~nwPJRomo92, December. 1980. 8. "lm roving the Restdentla1 Street Emron- merit.. 8. Sm,th 8 D. Appleyard, U.S.D.O.T., ~~$~~'~k~~~$g Policemen.,, J, p, - Clement. P.E.. pU& works. May. 1982. (Bates)". March 1.1582. garding the use and desirability of these speed humps. As these devices become greater public pressure that speed humps be installed on additional road- ways. The general public like these de- vices. In fact we've already received verbal requests and petitions from RSi- dents of nearly 10 other streets; and the 21. Constants: 1 Kph = 0.621371 mph 1 mrn = 0.0393701 in. 1 m = 3.280840 ft. 16 hr. vo(. = 95% adt. 2 , This article is based upon a rep( thored by Mr. Clement, copies 01 are available by writing to: MI Clement, P.E., Principal Engine6 Califprnia 97360. fjc Division, City of Thousand list is growing! It is further hoped that the State and Federal Departments of Transportation will also utilize such data in eventually adopting some uniform standards for these "geometric features of the roadways". 2;. ~s~~~~m~~~~~~~~p~~~~: e. cle- 11. "Responseof Vehideslo Pavement Undula- FgLG, Yigp"' 8 '. E. Bemardp universiv Of 12. "46th Street Speed Redudin Demonstra- tion". Washington. D.C.. Depactmenl of Transports- boo. Ma , 198,. 13. '&eed Undulations". City of Sacramento. California. July. 1981. 14. "Traffc Engineering in Sacramento". L M. Frink. Western I.T.E.. March-April. 1981. 15. "A hmpy Road Ahead?". C. Allen & L 16. "An Evalua!m of Speed Curtailing Bumps", A Turturici. Public Works. August, 1975. Wifomia Supreme Court Case ~0.494166-0. Filed June 1. 1982. J. P. Clem1 (F) is the Engineer 0' fic Engine€ sion for th Thousane California. ment holc Degree in References Walsh. Traffc Engineering. October. 1975. ing from 1. "Road HumDs for the Control of Vehicle State Polytechnic University, and Speeds". G. Wans. U.K. Oepartment of the Envi- rmment TRRL LR597.1973. tered Professional Engineer in 1) 2. '.S&ed Confrol Humps in Cuddbsdon Wa California with licenses in both cib fic Engineering. Cowley. Oxford', R. Sumner 8 J. Burlon 8 z: 17. -Rumford v. atY of Berketey, California-, .. . . - - ___ - - - . (- 0 0 .- 0 . * \ LIST OF CALIFORNIA JURISDICTIONS WITH ROAD BUMPS ON PUBLIC STREETS JULY 1983 e Jurisdiction Contact Phone Number Warren Siecke (91 6) 449-5307 2. City of Claremont Ismi le Noovlaksh (714) 624-4531 (714) 736-2279 4. City of Pasadena David Barnhart (21 3) 577-4230 7. City of Brea Gi 1 bert Calzada 3, City of Corona 5. City of Placentia - . John Garcia - (714) 993-81'31 6. City of Sacramento Richard Folkers (916) 449-5307 Terry Little (916) 440-5966 (415) 577-3411 Wayne Tanda (408) 277-5341 10. City of Santa Monica Ray Davis (21 3) 393-9975 11. City of Santa Rosa Basil Andrews (707) 576-5141 7, County of Sacramento 8. City of San Leandro Dan Arre 1 1 ano 9. City of San Jose ext, 227 12. City of Thousand Oaks John Clement (805) 497-.8611 ext. 243 %J ColsOdrSpa CAN ARl tw s\m\ V/LL€S( 0 0 e $* '1 - I \ LIST OF CALIFORNIA AGENCIES CONSIDERING USE OF ROAD BUMPS . JULY 1983 1. P1 acervi 1 le Michael Foster (916) 626-0606 2. West Covina David Nelson (213) 962-8631 3. Capitola Craig French (408) 475-7300 (ext. 436) 4, Marysvi 1 le Bill Frye (Tech) (916) 741-6421 5. Maywood Matt Binder (213) 996-2161 (Yuba County) 6. Saratoga Erman Dorsey (408) 867-3438 7. Pittsburg Detlef Curtis (415) 439-4915 8. Cudahy Matt Binder (213)- -996-2161 9. Pismo Beach ACE. Johnson (805 1 -773-4655 10. Duarto Dwight French (27 3) 921 -5321 11. Dixon Ron Tribbett (91 6) 678-2326 12. Bell Gardens Tom Brohard (213) 921-8215 13. La Habra Heights John Maulding (21 3) 921 -821 5 14. County of Sonoma Larry Pol 1 and (707) 527-2231 15. Corcoran Ron Hughes (209) 992-2151 16. Modesto D.J. Carmody (209) 577-5297 17. Benicia Charles Vosicka (707) 745-0510 18. Burl ingame Thomas Moore (415) 342-8931 20. Alameda County Raymond Burnham (41 5) 881 -6476 21. Culver City John Lathrop (213) 921-5791 22. Rosevi 11 e Larry Page1 (916) 783-9151 23. Oakland (Naval Public Sam Dyson (415) 466-2263 24. San Francisco Bill Marconi (41 5) 558-3608 25. San Luis Obispo Allen Tilton (805) 541-1000 9 Public Works (ext. 40) 19. Nevada City Roger Northern (916) 265-1411 Public Works ext. 222) Works Center 3 e e Chvl&~ud Vzlhgo hve Etm) I- 01 m la s oLnn.3 Chestnut I SpacingBetweenhuumpsapp. 500' Existing 85% Speed: 44 mph Existing Speed Limit: 25 mph Height of hump: 3 in Length of hump: 12 feet Tamarack The City of Sanego ,' NAGER'§ EPORT rG rfl * r DATE ISSUED: March 21, 1990 REPORT NO. 90-141 ATJENTION : T&LU Committee Agenda of March 26, 1990 SUBJECT : REFERENCE: The Use of "Speed liurnps" on City Streets Cormi ttee Consul tarit helysis T&LU 90-3 SUMMARY Issue - Should the Council direct the City Manager to develop a Council Policy for the installation of "Speed Humps" on City Streets? Kanager's Reconmendaxion - nirect the City Manager to conduct a test of the effect of Speed Humps on two City streets to develop a recommended practice, and if appropriate, a drzft Council Policy based on the test rssults, and tc /-%, \, IJ explore methods of financing the installation. Other Recommendations - None. Fiscal Im act - Approximately $12,000 for installation of Road Rumps at th'G + ocations This would be funded from the FY l.91 Annuzl Allocation for Road- way Channelization. BACKGROUND In a Memorandum dated October 30, 1989, Councilmember Pratt requested that the Transportation cnd Land Use Committee consider the possibility of using speed humps as a means to control speeding and reduce traffic OE residential streets. Councilmgmber Pratt mentioned that the City of Thousand Oaks has successfully used them to control the speed of vehicles, and that such devices could save money by reducing the need for heavy and costly police enforcement. tee Consultant's Analysis dated January 8, 1990 recommended that the City Man- ager review the information on speed humps, and develop a Council Policy for The Commit- their installation based on that analysis. a 2 0 DISCUSSION Speed humps ar2 pavement undulations used for the purpose of reducing speed, They are raised areas in the pavement surface extending across the traveled way typically 3-inches in height and 12-feet in length. limited use on public streets in the United States, but have been used more widely in Europe and in other countries. ple of a "speed hump." It should be noted that a speed hump is very different than a speed bump in that the speed bumps are short (1- to 3-fOOt) sections the; are commonly foufid in shoppins centers and other private drives. Staff reviewed studies of speed humps conducted in the Cities of Brea, CA; Sac- ramento, CA; Thousand Oaks, CA; Pasadena, CA; and Phoenix, AZ, as we71 as re- ports of studies conducted worldwide OR the same subject. In addirion, staff reviewed reports issued by the California Traffic Control Devices Ccrmmittee and the Institute of Transportation Engineers (ITE) on the effectiveness of speed humps as speed control devices. Pasadena and discussed the progress of their program, and inspected some of the existing installations. Althouah many California cities are using the speed huvxs, they have not been classified as "official tr6ffic contrF?-dfevlces'1,bx-arle considered to be "roadway design features." Also, there is no official policy for their in- stallation in the State Traffic Manuol. The California 'Vehicle Code (Section 440) describes "official traffic control devices'' as "arry sign, signzl, marking, or device, consistent with Section 21400, placed or erected by authority of a warning, or guidina traffic, but does not include island!;, curbs, traffic barri- ers, or other roadway design features." Therefore, speed hunps arz considered experimental at this time in the State of California. 21400 of the Vehicle Code also establishes the procedures to be followed by the Department of Transportation ir: order to establish stzcdiirds and specifications for traffic cor,trol devices." While there has .been a wide variety of shapes tested, cii-cular and ptirabolic arcs have been more commonly used, and there have been no significant differ- ences noted while using either of the above-mentioned sh<ipes. Effect on Speed There is unanimous consensus among all agencies that have studied the undula- tions 'in the fact that they do effectively decrease the prevailing speeds at .yarying degrees depending on their height. spread throughout the entire length of a road by spacing the undulations follow- ficant amounts of traffic to adjacent roads. had little or no effect on the average sound levels on the roads that were tested, and in some instances, the average noise level wtis actually reduced when the daily traffic was reduced. They have been installed in See enclosed Figure 1 showing an exam- 7- Staff met with Traffic Engineers in the City of public body or official haviiig juri.sdiction, for the purpose of requlating, Incidentally, Section Ih e decrease in speed can be evenly ing a specific formula. In addition, studies also show that they divert signi- They have iilso been found to have t, 0 a 3 -. r" Effect on Traffic Volume They've been found to divert some traffic to adjacent parzllel streets but ths actual amount of traffic diversion depends on the flow conditions of that parti cular area's street system. Effect on Traffic Safety There has been no proven direct effect of the undulations on traffic safety. Eowever, in most ot the cases studied, the speed humps we installed in low vol- ume residential streets where there was no significant accident hisTGFj?7Ti-- fact, a high accident rate has nct been the criteria for their instznation in these studies. It should be noted that there usually-are a combination of fac- tors including speeding that contribute to a pattern of zccidents at a particu- lar location. accidents. b!hile there has been only a few cases where the road humps have been questioned in a court of law, there is still not enough evidence to demonstrate conclu- sively what overall effects these pavement features have on traffic safety. Kost municipalities currently using bumps consider them experimental, and in some cases, such as the City of Pasadena, the project is currently on hold. There has been a somewhat uncontrolled proliferation lof the bumps in the Pasa- dena example where the basic warrants established for their installation have been cverridden in sone cases. It should be understoad that installatioh made against a City's own standards could increase the risk of successful litigation against the City. Effect on Emergency Vehicles Significant delays may be experienced by fire trucks, other emergency vehicles, buses, and large trucks when driving over the undulations. The reason for this is that they must pass over the undulations at relatively low speeds, under 20 mph, or else significant jolts to the vehicle, discomfort to occupants, and jostling of cargc will be experienced. It should'be noted that trucks and buse experience more dramatic effects since they are required to reduce their speeds at levels significantly lower than other smaller vehicles due to their longer wheelbase. However, speeding in and of itself does not necessarily cause cost - The direct cost of speed humps was found to range fron $500 t~ 51,200 depending on the geograpnic location and source of tunaing. Havance signing and painting is required, but their cost is minimal.7here is also additional engineering staff time required to implement the program. may be from a risk management stand point. Sources of funding vary from assessment districts to CIP funding. palities use both. They have had a very large number of requests, and their CIP allocation has It is not known how costly they Some munici- The City of Pasadena funds the installations through CIP's. - 0 4 increased to approximately one-hundred thousand for the last fiscal year. City of Phoenix uses the assessment district, and they have received very few requests through this type of funding. Warrants In its 1989 publication, Residential Street Design and Traffic Control, ITE - listed the following "Desirable design and location features." The Furthermore, most municipalities have warrants that are derived from the ones listed belolr!. o In gofile the undulation should have a Qenerally circular arc cross section on a 12-foot (3.541) chord with a maximum midpoint heiaht of 3 inches (7.5 cm) and an allowable constructior tolerance of plus or minus 0.5 inch (1.2 crn). 4-inch (10 cm) vblue recornvended in early research reports.) The undu latior, should extend across thcl roadway with the 12st 1 to 3 feet (0.3 to 1.0 m) tapered so thlat it becomes flush with the gutter pzn to main- (This recommended height is less than the tain drainage flows. o Undulations should be placed singly. Closely spaced pairs, though utilized successfully by some jurisdictions, do not appear an:' Fore or less effective than single undulations. Undulztions should be spaced zpproximately 550 feet (165 in) or less apart. Undulations should be placed at least 20C feet (60 m) away from inter- sections and sharp horizontal curves and be otherwise loczted so they are clearly visible for at least 2CO feet (60 VI. Specific positioning of undulations should consider access to utili- ties, driveway locations, and existing illumination. The undulations should be marked with warning sigfis at the device and pavement rnessoges in advance. plates, double yellow centerline marking in the vicinity of the undula- tion, and pavement markings on the device are optional. o o o o Advance-warning sicns, advisory speed o Unfortunately, major and collector streets which are residential in character are those on which traffic speed is a significant issue. However, undulations should not be utilized on these classes of streets because the level of restraint they impose is inconsistent with the functional purpose of the streets. Undulatioris should not be used on grades greater than 5 percent. Undulations should not be placed on primary emergency vehicle access/ egress routes nor cx important transit routes. o o 0 e ' _- 4 5 I. 6:;- - i..;.;;. i' : .- CONCLUSION B?;ed on current experience and research "Speed Humps" have been found to be effective devices used to reduce the prevailing speeds on streets classified as residential and/or local. They will, however, affect emergency vehicles' abil- ity to cross over them. Staff recommends that a test program be initiated in order to assess their ef- fect on city streets as it relates to traffic safety. The recommended location for installing the bumps should meet not only all the features listed above but the test sites must also be on unclassified streets typically carrying traffic volumes less than 3,000 ADT. We estimate that the direct cost for insta1:ation arid removal of the devices on two streets would be approxirriately S12,OOG. After a period of approximately six months after their installation, staff WOCrl' prcvide a stztus report to this committee oli the possibility of continuing or endinc; the program based on those findinss. ALTERNATIVES 1. . ... -.. . .. Clirect the City Manager to develop a Council Policy for the installation of Speed Humps without a testing period. This is not recommended because they continue to be considered experimental by the State--of California. @1:rect the City Manager to not implement the test, but to continue the re- search on "Road Bumps", and to advise this committee when more conclusive fir;dings become available based on the experiences of neighboring rnunicipal- ities. Given the relative success experienced by other municipalities, we believe thzt there may be certain conditions under which these devices can he successfully uti1 ized. lieu of this alternative. (5,?,; ,.:.-: :L' 2. . i- .. - We, therefore, recommend a testing program in Respectfully submi tted, m Severo Esquivel / Deputy City Manager --.. ROLL I ?;*SER/JLL ATTACHMENT Figure 1 - Sketch of "Road Bump" * !. \. .-:. "a _/ 0- >- a Q. z 0 Ln - - w E >- m W b Q 0 n a > 4. - z 0 a - \ / W (z , , REFLECTIVE T - 1ZU REFLECTIVE WHITE STRIPES @ 6' 0.c. >. ___ - - I_ WARNING Fl FEE , ]Tl<A.C. ?.'WAX, 12' TAW? STA VA%ES) OZ-AR-40W -tLIzI+ TXX COAT SECTION AA - lJJqncl,!AT,ou flFT,A I\ 7 - i> SFEED HUMPS SHALL )\KIT EE FLACED OVER MANHOLE, > a W I- U 0 - WATERGATES, JUKTlON CYANZEFS, Ric. 2)EOGE OF SFctEil HUMP %ULC €E 5 FEET MINIMUM FROM EDGE OF DZlVEWAY. 9 UHEMEVER FES16LE SFEED HUWS SHALL EE PLACED AT FROPERTY LINES IElSTEnD OF M1D-LOT. 4) WHEhJEVER POSSIBLE SPEED HUbtFs SHALL BE PLACED ADJACENT TO STREET LIGHTS. SIGN LOCkT IOSS. DIRECTED 5f Ek aN-~a~7+q~S!8 QF- ~ HUMP CROSS SE ~3f5cu"CwlJkJJn 0r;G YCTIOA ""y/Tij{ littii u WP+ I i id ! 4 c I I r-1 12' ire biry WI aawlego 1 (a MANAGER'S REPORT 4 DATE ISSUED: September 19, 1990 REPORTNO. 90-401 ATTENTION: T&LU Committee Agenda of September 2 4, 19 9 0 SUBJECT: REFERENCE: T&LU Report No. 90-141 Proposed Locations for Experimental "Speed Humps" on City Streets , SUMMARY Issue - Should ~Qeed humps be installed as proposed by the City Manager to study the; effects on travel speeds? ManaPer's Recommendation - Approve the proposed test locations. Other Recommendations - None. Fiscal Impact - Approximately $12,000 for the installation of 13 speed humps at the proposed two locations. BACKGROUND On March 26, 1990, the City Manager presented a preIiminary study of speed humps to the Transportation and Land Use Committee. The City Manager recommended that speed hump: be studied on City streets to assess their traffic impact. This recommendation was based on the experiences of other municipalities that have successfully used speed humps to reduce vehicula speeds and direct through traffic off of local residential streets. The T&LU Committee directed the City Manager to select two locations appropriate for the study. 0 2 t e * *. DISCUSSION The Traffic Engineering Division has received many requests for installation of speed humps on for the speed hump study. After studying these streets, it is staff's recommendation that speed humps be installed on and on Granada Avenue between Upas Street and North Park Way in the North Park area. Both of these streets are currently classified as local residential streets. In addition to slowing down traffic, a secondary effect of speed humps is the diversion of through traffic to adjacent classified t!!rough streets. Motorists using Granada Avenue as a through street are expected to divert to 30th Street, which is the preferred route. In the case of Westbrook Avenue, traffic is not expected to be diverted to adjacent streets because the traffic on Westbrook Avenue is local residential from the immediate vicinity. These two streets were selected based on the following facts: City streets. Staff has evaluated conditions on these streets to determine the optimal locations Westbrook Avenue between Spring Oak Way and Anmine Drive in the South Bay Terraces arm; 1. 2. Both streets are residential. 3. 4. 5. 6. A history of speeding problems with an 85th percentile speed over 34 mph. Geometric design; free of sharp horizontal curves within the limits of the study. Good safety record with few speed related accidents. Minimal variations in street grade within the limits of the study. Overall conditions indicate that these two streets are optimal locations to gather data for this study. < Traffic Engineers will coordinate the installation of speed humps with the community group representing the affected neighborhoods prior to their installation. In addition, all residents on the subject streets will be notified pnor to the installation of the speed humps. Appropriate warning signs and pavement markings will be installed to alert motorists of their presence. Before and after the installation of the speed humps, studies will be conducted, inchding speed surveys, traffic volumes analysis, accident pattern analysis, and residents' acceptance through an "after" survey, not only on Westbrook Avenue and Granada Avenue, but also on the adjacent streets. We will also study the effects speed humps have on emergency vehicles, trucks and motorcycles. It is anticipated that the speed humps will be installed within 120 days of approval of this report. These studies will allow the engineers to compare and determine if the traffic conditions have indeed improved due to the changes implemented on the road. CONCLUSION The locations recommended for the testing of speed humps will provide the optimal conditions to fully assess their impact and benefit on City streets. Staff will report back to the T&LU I e * e 3 Committee six months after installation of the speed humps with final recommendations 01 continuation of the program. If appropriate, staff will develop a draft Council Policy for thr criteria for the installation of sped humps. Staff will also identify potential methods of fundin, future installations. *.' ,. ALTERNATIVE Direct the City Manager to test the speed humps at different locations, or to abandon the tes program. Respectively submitted, K&Ji-Y* Severo Esquivel Deputy City Manager ROLLINGEWJLL ATTACHMEhTS - Sketch of proposed locations for Speed Humps .- a me e 2- 3 a, North Park Way Approximate “speed hump locations a Park area a, > -a* ,C ‘ al’ong Granada Avenue in the North a 3 Gunn Street z u) 7 (D m ct ct cc 3 c a Landis Streei Spacing between humps app 400 ft Existing 85% speed 38 mph Existing speed limit 25 rnph Height of hump 3 in (HI Length of hump 12 ft (L) Typical sign location Typical Speed Hump location Upas Street Atachment 1 a I a er --- An ?e Drive *= *b ' Seabrook lane Shadewcod Lane Spacing between humps: app 400 ft. Existing 85% speed. 35 mph Existing speed limit. 25 mph Height of hump: 3 in, Length Of hump: 1 2 It. Sherbrook Street Grove View Road Typical sign location Montcli f f Road Typical speed hump location *t Attachment 2 e 0 -' "-7 - F ,6 . 31 flay, /991 flUyOR LeWid /2OO ELm Ave. catidbud, [A, 7200~ Deun Muyon lewi~: On Tuehduy, j'une. //, ut 6PM the CunL~lud Citg Council. wiLL ne the upped o{ the Sufety Comminnionn necommendat ion, ReLutive the npeeding pnobLem un Pontiuc DRLV~. Z wiLL le in Onunp County on j'une /I, 1 huve Lived ut 3558 Pontiuc Dnive dince /979. thud thin Letten. Being Refined, huve witnenned numenoun If neun uccidentn" of neighbonn attempt to buck out of thein dnivewuyn, to 50 mile pen houtt npeedetn The cunve~ on PoniLac dL~ve, denLen olnenvat~on Ly Lo& the A und the JzomeowneR and muken npeedn OV~R 25 MPh' hu~u~doun. The necent PoLice Depuntment uttention to the pnoblem in appn howeveit Z have neen no impnovement of the pnobLem. Lately Z /? noticed u numben o{ npeedenn between the hounn o{ 6-7:30 pfl., pnimundy in u South to Alonth dinection. /hem UR~ nix young childnen in OUR nhont bLock. A child woul LittLe cXunce o{ LLURVLVUL ut the pnenent duy npeedn on Pontia und uttempting to uvoid the 4 - P0ntiGt.C DRiVe in U diAULLteR WUiting to eRUpt. We ReAidenfL ha Xud tweLve I1 Lucky yeunn II . Duily the tnu{{ic Lecomnheuvien un mote neckleu-. Joua Council. munf take skin nuhject ~ee~.uunLy betone you find You lecorne digzutueen. to Leftenn u{ dymputhy. 1,- iE $43 78 *J IO ~~~~~~ eRt E. 6 ' -#' on f+ifl"m cnn flUiOR UshC Ret. 3558 Pontiuc DR. f6/9/ 434-3521 k -47/ r74 +/lM/ 0 0 ,a \ I-- -’ Y Presented by: Chestnut Hills Community Ac.tion Group PROPOSED RECOMMENDED PRACTICE Institute of Transportation Engineers 525 School Street, S.LJ. Suite 410 Washington, D.C. 30024-2719 USA BmLu?u 4- Lac : Lb I -- ,-I - 1 s- ?- e. I 0 0 m '1 4. -1 STANDAFB ITE METRIC CONVERSIONS During the service life of this document, use of the metric system in t United States is expected to expand. The following common factors represe the appropriate magnitude of conversion. The quantities given in U. customary units in the text, tables, and figures represent a precision lev that, in practice, typically does not exceed two significant figures. making conversions, it is important to not falsely imply a greater accuracy the product than existed in the original dimension or quantity. Howeve certain applications, such as surveying, structures, curve off s calculations, etc., may require great precision. Conversations for su purposes are given in parentheses. Area - Length 1 inch = 25 mm (millimeters--25.4) 1 square inch = 6.5 cm (6.41 1 inch = 2.5 cm (centimeters--2.54) 1 square foot = 0.09 (0.0929) 1 foot = 0.3 m (meters--0.3048) 1 square yard = 0.84 m (0.8' (hectares--0.405) 1 mile = 1.6 km (kilometers--1.61) 2 2 0.4 - 1 yard = 0.91 m (0.914) 1 acre - I Volume Mass 1 cubic inch = 16 ~m~~(16.39) 1 Ounce = 28 gm (gram--28.34 1 cubic foot = 0.028~ (0.02831) 1 pound = 0.45 kg (kilograms. I cubic yard = 0.77m (0.7645) 0.454) 1 quart = 0.95L (liter--0.9463) 1 ton = 900 kg (907) 1 gallon = 3.8 L (3.785) f> Speed Light foot/sec. = 0.3 m/s (0.3048) 1 footcandle = 11 lu3 (lume miles/hour = 1.6 km/h (1.609) per m---J,0.8 (Sandelas pe mc-- 3 - 426) I footlambert = 3.4 cd/m- Temperature To convert OF (Fahrenheit) to "C (Celsius), subtract 32, then divide by 1.8. For other units refer to the American Society of Testing Matetials (1916 F Street, Philadelphia, PA 19103) Standard for Metric Practice, E380. 0 0 e k. .. CONTENTS RECOMMENDED GUIDELINES FOR THE DESIGN AND APPLICATION OF SPEED HUMPS P1 LIST OF FIGURES FOREWORD 1-00 INTRODUCTION ........................... 1.01 Purpose.. ........................ 1.02 Speed Humps Versus Speed Bumps .............. 1.03 Previous Research and Experience ............. 1.04 Conclusions ............ .I. .......... 1.05 Use of Guidelines ..................... 2.00 GUIDELINES FOR SPEED HUMP USE .................. 2.01 Engineering Study ..................... 2.02 Street Classification and Use ............... 2.03 Street Width and the Number of Lanes ........... 2.04 Street Grades ....................... 2.05 Horizontal and Vertical Alignment ............. 2.06 Sight Distance ...................... 2.07 Traffic Speeds ...................... 2.08 Traffic Volumes ...................... 2.09 Traffic Safety ...................... 2.10 Vehicle Mix ........................ 2.11 Emergency Vehicle Access ................. 2.12 Transit Routes ...................... 1 2.13 Citizen Support ...................... 1 3.00 COMMUNITY RELATIONS AND ADMINISTRATIVE PROCEDURES ........ 1 3.01 Supporting Ordinances and Regulations ........... 1 3.02 Staff Evaluation ..................... 1 3.03 Coordination Procedures .................. 1 3.04 Speed Hump Request Procedures ............... 1 3.05 Removal Procedures .................... I 3.06 Cost ........................... 1 v 0 L . 'I PAGI 4.00 DESIGN AND CONSTRUCTION CONSIDERATIONS .............. 11 4.01 Dimensions and Cross-Sections ............... 11 4.02 Spacing and Location ................... 13 4.03 Traffic Control ...................... 17 4.04 Installation Angle .................... 18 4.06 Roadway Edge Treatments .................. 18 4.07 Coordination with Street Geometry ............. 22 4.09 On-Street Parking ..................... 22 4.10 Streetlighting ...................... 22 4.11 Construction Materials .................. 22 4.12 Construction Procedures .................. 22 4.05 Drainage ......................... 18 4.08 Coordination with Traffic Operations ........... 22 5.00 MONITORING AND EVALUATION .................... 23 5.01 On-Site Observation .................... 23 5.02 Speed Studies ....................... 23 5.03 Volume Studies ........... t .......... 24 5.04 Stop Sign Obedience .................... 24 5.05 Travel Time Studies .................... 24 5.06 Accident Analysis ..................... 24 5.07 Resident and Driver Surveys ................ 24 5.08 Noise Analysis ...................... 24 5.09 Vibration Analysis .................... 25 5.10 Pedestrian. Bicycle. and Social Activity ......... 25 5.11 User Cost Analysis .................... 25 5.12 Vehicle Emission Analysis .................. 35 6.00 OTHER CONSIDERATIONS ....................... 25 6.01 Liability Concerns .................... 1-5 6.02 Vehicle and Cargo Damage ................. 26 6-03 Coordination with Pedestrian Crossings .......... 26 6.04 Aesthetic Considerations ................. 26 6.05 Incorporation in New Street Design ............ ?h 6.07 Maintenance Issues .................... 2; 7.00 SOURCE MATERIALS ......................... 28 6.06 Enforcement Needs ..................... 16 e 5 * 1' RECOMMENDED GUIDELINES FOR THE DESIGN AND APPLICATION OF SPEED HUMPS This recommended practice was developed and approved in ac formally adopted Institute procedures which are designed to he; received has been considered in order that the recommended practice WOI represent the best consensus obtainable on the state-of-the-art at the time approval. This report was developed by an TTE Special Task Force appointed in July 1' by the Technical Council. Members of the Task Force were: all interested parties are given opportunities to provide inpu - 111 David E. Barnhart, P.E. (M) Richard F. Beaubien, P.E. (F) Bert Beukers, P.E. (F) Ian C. Boyd, P.E. (F) Howard R. Chapman, P.E. (F) John P. Clement, P.E. (F) Charles E. DeLeuw, Jr. (M) R. Marshall Elizer, Jr., P.E. Chairman (F) William E. Haro, P.E. (M) I Jim Jarvis (A) William R. McGrath, P.E. (H) Kenneth Melston, P.E. (F) Jere E. Meredith, P.E. (F) Andrew P. O'Brien (M) Sheldon I. Pivnik (F) Thornas A. Sohrweide, P.E. [A) Burton W. Stephens Roy L. Sumner [M) Douglas W. Wiersig (A) This report was reviewed by Department 5 of the ITE Technical Counci. ?embers of the Technical Council Department 5 Standing Committee < Transportat ion Design at the time this report was approved wert The Chairman of the Technical Council was and the Vic Chairman was Certain individual volunteer members of the Institute recommended practic developing bodies are employed by Federal agencies, other governmenta offices, private enterprise, or other organizations. Their participation i the Institute recommended practice developing activities does not constitut government agency or other organization endorsement of any of the Institut recommended practice developing bodies or any Institute recommended practice which are developed by such bodies. Any suggestions for revisions to this recommended practice or appeals shoul be submitted to the ITE Director of Technical Affairs: Institute o Transportation Engineers; 525 School Street, S.W.; Washington, D.C. 20034. f 0 e. . . .. FOREWORD Until the 1970's the effects of motor vehicle traffic on the quality of UI residential environments were largely neglected as a serious transportal problem. In the past decade, however, a number of converging forces 1 increasingly brought these effects to the attention of both citizens and 1( transportation officials. Many local governments are finding themselves UI intense pressure to reduce the speed and volume of traffic on neighbor1 streets to address both real and perceived safety and quality of life issue Increasing levels of automobile ownership, smaller household size, longer t lengths, poorly designed residential street systems, and under-desig arterial roadways in urban areas are some. of the factors contributing continued traffic growth and vehicular intrusion in residential areas. At same time, capital shortages, rising construction costs, and environmen concerns are concurrently limiting the future expansion of the transportat facilities necessary to address these problems and continually increas needs. As a result, congestion on arterial streets is increasing in II urban and suburban areas and more traffic is diverting to local resident streets to bypass congestion. In some cities, street systems are incompl or have been poorly planned resulting in local residential streets being only facilities available to serve collector and traffic movement functio Whatever the reason, increased traffic volumes and speeds along lo residential streets often prompt citizen concerd and protest, even wh traffic vcilumes are not particularly large. Residential traffic problems can obviously take a variety of forms. following categories of problems or issues are those most often heard w dealing with neighborhood traffic concerns. Traffic Safety -- The occurrence of accidents, and more frequer, the fear or expectation that accidents or near-accidents may occ is often a leading problem. Much citizen sensitivity to traf . .stems from a desire for safer streets. In some cases these stre! .serve as primary pedestrian routes for school children which rei to amplify these concerns. . Traffic Speed -- Excessive speed is a frequent resident complaii In some cases, the speed of the majority of vehicles is a prob while in other cases it is only a few "fast" drivers. The negat reaction to speed is often a translation of concern over safetv I high noise levels. Vehicles driven at high-speed, even if 01 occasional, are seen as an insult by thoughtless drivers to peace, quiet, safety and quality of life within the neighborhood. . Traffic Volumes -- The total amount of traffic is another frequ,. cause of residential complaints. As with speed, complaints ab( high volume are often a reflection that speed and safety issues a: exist. s 0 0 ,. Noise, Vibration and Air Pollution -- These are aspects affect the basic quality of neighborhood life. While less visible quoted than the previous problems, these concerns can be signific of larger andlor older vehicles, if street curvature is severe, if the pavement has a rough surface. Traffic Source -- In most cases, "through'' traffic is the source resident complaints although quite often the problem lies G traffic generated by area residents. Traffic Composition -- Certain types of traffic are also pr causes of annoyance, especially trucks, buses, and motorcycles wt create more noise, fumes, vibrations and are perceived n hazardous than automobiles. Reduction of Street Activities and Social Activities -- When traf volume, speed, and large vehicle mix increase, the desire residents to meet and converse on the street is reduced. Similax the comfort level of parents to allow children to play in fr yards and on sidewalks is reduced. Other physical activities E particularly if major percentages of the traffic stream are made as walking and jogging are also affected. Impacts on Land Use -- The presence 1 of excessive traffic discourage residential land uses and leads to increased resic turnover and neighborhood instability although this is not alk the case. There is also some evidence that streets with gre; auto accessibility may be more susceptible to residential crime. Appearance, Identity, and Maintenance -- Excessive traffic L often detract from the more positive features of a neighborf thereby affecting the neighborhood identity and cohesion which reduce some residents' incentive to maintain their properties. While proper subdivision planning and residential street design are the n effective methods of avoiding residential traffic problems, these goals not always achievable. Where problems exist traffic management programs t been successfully demonstrated as effective strategies for addres: residential safety and quality of life issues. They remain, however Certain techniques and strategies appropriate and successful in one particr neighborhood may not be appropriate in a different setting. In many case: successful neighborhood traffic management program is dependent more on put participation and consensus building than on the particular traffic cont techniques used. While neighborhood streets are typically public property thus belong to everyone, most residents feel an "ownership" of their strf and therefore take vocal exception to outside and discourteous drivers. Traffic management strategies employed to address residential traffic conct can generally be assigned to four basic categories: challenging task from an engineering, political, and institutional standpoi 1. Establishing and enforcing general laws and ordinances pertaininj speed limits, intersection control, and parking regulations. ' strategy should generally be the first used to attempt to SI evolving neighborhood concerns. C 0 0 r % 2. Installing traffic control devices that provide specific regulato warning, or guide messages to motorists. These should be u judiciously and in conformance with the Manual on Uniform Traf Control Devices. 3. Installing geometric design features that manage the physi movement of vehicles or pedestrians within the roadway or withi neighborhood. These should be used as a remedial technique o when the above methods have proven ineffective. 4. Educating residents to better understand the causes of traf problems, potential solutions to those problems, and advantages/disadvantages of implementing these solutions. 'I strategy should be pursued any time neighborhood concerns are be addressed. This recommended practice provides guidelines for the design and applicat of speed humps, a roadway geometric design feature intended to physica reduce vehicle speeds. Other types of geometric design features that are addressed in this document but could be considered in a residential traf management program are raised intersections, rumble strips, chokers, traf circles, median barriers, diverters, forced-turn channelization, cul-de-sacs. These features are designed to attradt special attention, red vehicle speeds, and/or physically restrict-or prevent vehicle movement alon roadway or within a neighborhood. Geometric design features should genera be installed only after less restrictive actions have been considered, and no event should their use be intended to allow or encourage the use of pub streets as playgrounds. The Institute of Transportation Engineers has recognized the need for pro\ ing transportation professionals and community leaders with strategies techniques for creating compatible relationships between residential neight hoods and streets. In an attempt to address that need the Institute developed Residential 'Street Design and Traffic Control, a book that fk discusses the history and causes of residential traffic problems. It provj information that will hopefully assist the transportation professional understanding and finding solutions to those problems. 0 e * 1.00 INTRODUCTION 1.01 Purpose The purpose of this recommended practice is to provide guideli for the design and application of speed humps which considered to be a technique to control vehicular traffic spe along a roadway. They consist of raised pavement constructed placed in, on and across or partly across a roadway. For a roadway geometric design feature whose primary purpose is reduce the speed of vehicles traveling along that roadway. Wh such as traffic diversion, that is not their primary inter purpose. purposes of this recommended practice, speed humps are defined there may be' certain side effects to speed hump installati 1.02 Speed Humps Versus Speed Bumps A speed "hump" is a raised area in the roadway pavement suri extending transversely across the travel way (see Figure I. Sometimes called pavement undulations or "sleeping policeme speed humps normally have a maximum height of three to f inches with a travel length of approxhnately twelve feet. A speed "bump" is also a raised pavement area across a roac and generally has a height of three to six inches with a ler of one to three feet (see Figure 1.1). Speed bumps are typic: found on private roadways and parking lots and do not tend exhibit consistent design parameters from one installation another. SPEED SPEED HUMP BUMP Figure 1.1 . I) -2- e * From an operational standpoint, humps and bumps .have critica different impacts on vehicles. Within typical residential sp ranges, humps create a gentle vehicle rocking motion that cau some driver discomfort and results in most vehicles slowing near 15 m.p.h. at each hump and 25 to 30 m.p.h. between prope spaced humps in a system. At high speeds the hump can act a "bump" and jolt the vehicle's suspension and its occupants cargo. A bump, on the other hand, causes significant dri discomfort at typical residential speeds and generally results vehicles slowing to 5 m.p.h. or less at the bump. At high spe suspension quickly absorbs the impact before the vehicle body react. In general, bicycles, motorcycles, and other vehic with rigid or near-rigid suspensions are more susceptible damage and loss of control from humps than vehicles with flexi suspensions. However, speed humps represent a lesser risk those vehicles than do speed bumps. Speed humps have the advantage of being largely self-enforc and of creating a visual impression, real or imagined, tha street is not intended for speeding or "through" traffic. ! items to consider prior to speed hump installation are tl initial construction and continuing maintenance costs, potential negative impact on emerggncy and service vehic. increases in vehicle noise, the imposition of inconvenient acc to some parts of the neighborhood, and, to some, tl appropriate for use at all hours of the day and night. addition, it is mandatory that they be supported with : combination of traffic control devices such as signs anc pavement markings to warn motorists of their presence indicate the expected and appropriate behavior. Where designed and installed with proper planning and enginee review, speed humps have generally been found to be effectivc controlling vehicle speeds without increasing accident rates. fact, some studies indicate that speed hump installstions actually reduced accident rates on residential stre Additionally, there is no evidence in the source nater reviewed for this report indicating that properly designed installed speed humps have caused or contributed to accident increased accident rates. Within the United States speed bumps of varying design have routinely installed on private roadways and parking lots wit the benefit of proper engineering study regarding their de and placement. Speed humps, on the other hand, have evolved extensive research and testing and have been designed to acl- a specific result on vehicle operations without impc unreasonable or unacceptable safety risks. The guidelines speed humps as presented in this document are primarilv b upon those experiences. bumps tend to have less overall vehicle impact because unsightliness. They are also static and therefore must w 0 c -3- * 1.03 Previous Research and Experience Speed humps were originally developed in the early 1970's by Transport and Road Research Laboratory (TRRL) in Great Brita TRRL first tested along a test track various hump signs shapes on several vehicle types operating over a range of speel From this work the "TRRL" parabolic profile hump was develop1 Since then speed humps have been extensively tested and used Europe as well as Australia and New Zealand. The U.S. Fede Highway Administration (FHWA) also performed "off-road'' test of the TRRL humps in St. Louis in 1979 and deemed them safe proceed with public street tests. In addition, an emerg number of cities in the United States and Canada either use have tested speed humps since the early 198O's, and in Novem 1983 a Subcommittee of the California Traffic Control Devi Committee issued a final report which endorsed the prudent use speed humps on public streets. Recent research in Australia has developed an alternative des to the "TRRL" profile humps developed in Great Britain. Research Board (ARRB) have yielded observations and rest similar to their English counterparts. The flat top section usually constructed of brick paving' with asphalt or concr ramps and has generally been found more aesthetically accepta than non-brick treatments. This design tends to reduce deformation problems experienced with asphalt humps 'but increase vehicle noise and maintenance requirements. The results of speed hump research and testing can be genera summarized as follows: - Traffic speeds are decreased at the humps and at locati between properly spaced successive humps. Speeds of fastest drivers are affected as well as those of "aver: drivers. The speed distribution generally narrows with greatest effect on higher vehicle speeds. Speed reducti generally remain constant over time. so-called "flat-topped" road humps tested by the Australian F - A single hump will only act as a point speed control. reduce speeds along an extended section of street a se of humps is usually needed. - Speed humps will often divert traffic to other stre especially in those situations where a significant am of traffic is using the street as a shortcut, detour overflow from a congested collector or arterial road Volume reductions are also affected by the number spacing of humps and the availability of alterna routes. - Speed and volume modifications caused by humps tenc: remain constant over time. 0. v -4- c .. - Speed humps have not been found to pose a traffic sa hazard when properly designed and installed at appropr locations. In fact, accident experience generally rem stable or decreases due to reduced speeds and vol thereby improving the inherent safety of a partic street or residential area. - Where humps are successful at reducing speeds, thert probably little net change in road noise or possibly ev reduction in noise levels. Traffic noise will gener decrease with fewer vehicles and lower speeds, but n may increase at the hump, particularly if signifi numbers of trucks use the street. - Adequate signing and marking of each speed hump essential. - The need to slow for speed humps tends to have a nega impact on air quality and energy consumption assui traffic volumes remain the same. For comparison purpo this impact is typically less than the effects of a sign installation. - Large trucks, buses, and emerggncy vehicles must pass humps at relatively low speeds or significant jolts to vehicle, discomfort or injury to occupants, and jostlin cargo will be experienced. Speed humps have been usel deter trucks and larger vehicles from using partic streets. - The majority of local street residents will norm support speed hump installations and endorse t continued use. 'rt should be noted that some speed hump installations in United States and other countries have proved unsuccessful ultimately been modified or removed. Factors resulting in t. removal have included the following: - Residents' dissatisfaction over the "gentle" hunp de (as opposed to the more drastic bump) and its perce inability to dramatically slow vehicles or reduce tra volumes to a desired level. - Undesired traffic diversion to other residential street - Aesthetics of the humps and associated signs and markin - Increased noise level at the hump caused by vehicle roc and acceleration/deceleration, - Impacts on snow plowing and other Street mainten functions. e -5- v . .: - Concerns with impacts to emergency vehicle response. - Concerns over liability. - Funding for the initial and continued maintenance costs .. the hump and its traffic control devices. The materials reviewed in the preparation of this report listed in the "Source Materials" section of the report. ' list also includes documents that could not be obtained speed hump user. Table 1 is a list of those agencies identified in the SOL materials that have tested or used speed humps as resident traffic management devices. review but may be of interest or assistance to the poteni I J ,w a -6- TABLE I PARTIAL LISTING OF AGENCIES WITH SPEED HUMP EXPERIENCE United States and Canada Phoenix, Arizona Jefferson County, Colorado Agoura Hills, California Washington, D. C. Brea, California Hillsborough County, Florida Camarillo, California Orlando, Florida Claremont, California Seminole County, Florida Corona, California Tampa, Florida Palo Alto, California Temple Terrace, Florida Pasadena, California Titusville, Florida Placentia, California Fulton County, Georgia Sacramento, California Wichita, Kansas Sacramento County, California Rockville, Maryland San Jose, California Boston, Massachusetts San Leandro, California Deephaven, Minnesota San Luis Obispo, California St. Louis, Missouri Santa Monica, California Omaha, Nebraska Santa Rosa, California Columbus, Ohio Simi Valley, California Toledo, Ohio Thousand Oaks, California Oklahoma City, Oklahoma Westlake Village, California Dallas, Texas Ottawa, Ontario, Canada Bellevue, Washington Toronto, Ontario, Canada Seattle, Washington Vancouver, British Columbia, Canada Apple ton, Wisconsin Winnipeg, Manitoba, Canada Knternat ional Australia Polland Belgium Israel Canada Japan Finland New Zealand France Norway Germany South Africa Great Britain Sweden Research Agencies Australian Road Research Board (ARRB) Federal Highway Administration (FHWA, United States Department of Netherlands Study Center for Traffic Engineering Transport and Road Research Laboratory (TRRL), Great Britain Transportation) 0 w -7- 1.04 Conclusions A5 discussed above, extensive research and use throughout Gr Britain, Australia, the United States, Canada and other countr indicates that the use of a properly designed speed hump or sp hump system, installed using the proper engineering analysis judgment, can be a useful geometric design feature to man traffic speeds on roadways intended to serve as local resident streets. Speed humps have been found, in general, to red traffic speed, volumes, and accidents depending on site-specific circumstances of the installation. In additi they discourage through traffic from using a local street as alternative route to inconvenient or congested arterial i collector systems. Despite concerns over liability , vehic damage, and emergency vehicle impacts, these problems have I occurred or have been found to be insignificant when consider the positive aspects of humps. However, speed humps are not cure-all for residential street traffic problems and should applied only where sound engineering judgment justifies thc use. Other passive and active devices and techniques should considered and possibly tested to determine if less restrict: concerns. Speed humps should not be considered an option to g( residential planning and subdivision'street design, nor shot they be used to convert streets to playgrounds or otherw: encourage pedestrian activity in public streets. The lack of guidance and heavy reliance on individual judgme has led to hump-type installations that incorporated PC designs, improper roadway geometric coordination, poor choice construction materials, methods, and absence of needed signs i markings. The safety of speed humps and their ability to perfc their intended use is directly contingent upon their pro€ design and application. When it is determined that a resident] traffic management problem exists and that speed humps are appropriate technique to reduce or eliminate the problem, tf ITE Recommended Practice will assist in the design : application of those geometric design features. forms of residential traffic management will address tht 1.05 Use of the Recommended Practice This LTE Recommended Practice is to be used in conjunction w: good engineering practice. These guidelines do not constitu either final or complete design criteria for speed humps, spe hump systems, or residential traffic management control prograir Local conditions must be evaluated for all speed hL installations. In addition, specific terrain, weather, traffi or land use characteristics may require local modification these guidelines. Other documents such as the ITE Recommenc Guidelines for Subdivision Streets: A Recommended Practic Residential Street Design and Traffic Control, and other standz practice documents should be consulted as necessary. a w -8- . t- 2.00 GUIDELINES FOR SPEED HUMP USE 2.01 Engineering Study Speed humps should only be installed to address documented saf or traffic concerns supported by traffic engineering studies, after consideration of alternative traffic control measures. Since speed humps may divert traffic to other street faciliti an estimate of the amount and location of that diversion sho be made so that the potential impacts of the proposed humps be fully considered. If the humps are expected to create eq or greater traffic problems on another residential street, t should not be installed. 2.02 Street Classification and Use Speed humps should only be installed on those roadway facilit functionally classified as "local" streets as defined in A Pol on Geometric Design of Highways and Streets published by MSF the American Association of State Highway and Transportat Officials. These streets generally permit direct access abutting lands, connect to higher clsssification streets, of the lowest level of mobility, usually contain no bus routes, deliberately discourage service to through traffic moveme Further, these local streets should be generally residential nature. 2.03 Street Width and Number of Lanes Speed humps should typically be used only on streets with no n than two travel lanes or where the overall pavement width is greater than 40 feet. In addition, the pavement should have E - surface and drainage qualities. 2.04 Street Grades Speed humps should generally be used only on streets with grz of 8% or less approaching the hump. When installed on strc with significant downgrades, special care should be taken ensure that vehicles will not approach the humps at excess speed. 2.05 Horizontal and Vertical Alignment Speed humps should not be placed within severe horizontal vertical curves that may result in substantial lateral vertical forces on a vehicle traversing the hump. General humps should be avoided within horizontal curves of less than feet centerline radius and on vertical curves with less 1 minimum stopping sight distance. If possible, humps should located on tangent rather than curve sections. V 0 -9- .. 2.06 Sight Distance Speed humps should generally generally only be installed wh the minimum safe stopping sight distance (as defined in AASHT A Policy on Geometric Design of Streets and Highways) can provided. 2.07 Traffic Speeds Speed humps should generally only be installed on streets wt- the posted or prima facie speed limit is 30 m.p.h. or lo Speed humps should not be used on streets where the majority vehicles travel at relatively fast speeds, e.g., 45 m.p.h. greater. When speed humps are installed to address speeding concer studies should be performed to confirm the magnitude and ext of the speeding problem to ensure that the installation of hu can be expected to appreciably address that problem. 2 -08 Traffic Volumes 1 Speed humps should typically be installed only on streets with average daily traffic volume of 3,000 vehicles or less. Gh humps are sometimes installed on streets with higher volum their use should receive special evaluation and justif icat before approval. 2.09 Traffic Safety When installed to address documented or anticipated vehicle pedestrian accidents, the causes of those accidents should susceptible to correction by speed humps. 2.10 Vehicle Mix Speed humps should normally not be installed on streets t carry significant volumes (greater than 57) of long wheel-b vehicles unless there is a reasonable alternative route for tli vehicles. Special consider~~tion should also he given motorcycle, bicycle, and other types of special vehicles that the street. The impacts that speed humps may have on th individual vehicle types should be considered in the decision install humps, and ultimately considered in their design locat ion. 2.11 Emergency Vehicle Access Speed humps should not be installed on streets that are defi or used as primary or routine emergency vehicle access routes. -- 7 * -10- 2.12 Transit Routes Speed humps should generally not be installed along streets b established transit routes. However, if humps are installed transit routes their design should consider the spec operational characteristics of these vehicles. 2.13 Citizen Support When speed humps are installed in response to citizen requests documented majority of the residents along the affected port of that street should ideally support their installation. 3.00 COMMUNITY RELATIONS AND ADMINISTRATIVE PROCEDURES 3.01 Supporting Ordinances and Regulations Before initiating a speed hump installation program, agenc should first adopt the appropriate policies, regulations, anc ordinances to govern elements such as the community involven process, hump design and locatio4 criteria, cost shar relationships, installation and maintenance requirements, evaluation/modification procedures. 3.02 Speed Hump Request Procedures Resident surveys should be required to determine support speed hump installation after it is determined that a partict street is eligible for humps. Ideally, a, majority of residents should be in favor of the installation a~ consideration of alternative traffic control and trar management techniques. 3.03 Staff Evaluation An adequate engineering and safety investigation of any reqt should be made to determine that the agencies' adopted guide11 are met for speed hump use. Since speed humps may have a wide ranging impact not only on vehicles crossing them but also on the residents living on immediate and nearby streets, their installation should typic: be studied within the context of a overall Neighborhood Tral Management study. Such a study would involve thorough proce: for considering, evaluating, implementing, and monitoring SI humps and any other traffic management techniques utilized. 7 e -1 1- . I. 3.04 Coordination Procedures Proposed speed hump installations should be reviewed by police, fire , ambulance and oth.er emergency service departmer adjacent neighborhood residents that may be impacted by the SF hump installation, and other potentially affected groups suct transit operators and refuse collection agencies. Commc process. If humps are to be installed, residents and affected agenc should be notified of the exact objectives, timing, location other relevant details of the installation. It is also advis: to meet with emergency service providers to more fully in1 them of the hump's expected impacts on special vehicle types various operating speeds. received should be fully considered in the decision-mal 3.05 Removal Procedures Removal of speed humps should only be considered after adequate review period and subsequent engineering analysis been performed to determine the traffic characteristics along route and the impacts to the remainink street system. If a f is being removed due to a lack of public support, a majorit) residents should typically support its removal. Before making a decision to remove speed humps, all petitio1 originally requesting the installation should be given opportunity to comment on the proposed removal. 3.06 Cost Consideration should be given to a possible requirement those individuals requesting speed humps be required participate in the funding of their installation, maintens1 and removal, if necessarv. Regardless of funding source, it critical that adequate and ongoing resources be allocated properly inspect and maintain the hiimps and supporting device: 4-00 DESIGN AND CONSTRUCTION CONSIDERATIONS 4.01 Dimensions and Cross-Sections FOK typical residential streets the most widely-used circu parabolic speed hump (TRRL profile, 3", ,!I' or 4" maximum) shown in Figure 4.1. The 3" hump can be expected to cause sp~ of from 30 to 25 m.p.h. at the hump, with a 4" hump crea crossing speeds of 15 to 30 m.p.h. Humps should not exceed A height, and where significant percentages of trucks, buses, other long-wheel base vehicles are expected, an approximatc height is generally considered more acceptable. An alterna design that has been successfully tested in Australia is show Figure 4.2 (flat-topped). Site specific roadwav and trn 0 -12- 0 -_ -il .. 0 0 056 1.07 1.53 1.99 2-31 1.13 1.89 3-11 228 340 JY8 3.50" 433'5/Efp )fuHp 0 l.67 /.?8 23 2.W 4?67 Ldl .?fz 2% JWR + 3' spf&p HUMP 0.bY 1.22 /.75 2.22 z.6Y 3.m 3.31 1% 3.75 J8Y 197 Y.oo'+ 4"5P€€ONUHP 0.11) 0.Yz 1.31 IIi1iC44r4 ++4)+*J++t *- 6' /L * - _--. . - - ____ . g Figure 4.1 I - 125 m or8.6m . "1 ,I I I I t,, mm 2 brddicrg d Figure 4.2 0 -13- e .._ -. characteristics should be evaluated to determine if one of t1 designs, or an alternate, is appropriate for the traffic roadway conditions at the installation location being considei 4.02 Spacing and Location Speed humps within a series are generally placed from 200 feet 750 feet apart. On a street with desirable maximum opera1 speeds of 30 m.p.h., humps should be spaced at approximately foot intervals. Figure 4.3 (from FHWA Report No. ED-814 illustrates the general relationship between hump spacing influence results, an empirical relationship between hump spac and speeds has been developed in Australian research effoi Based on data from the United Kingdom and Australia, following equation was derived: For a 4" high speed hump: vehicle speeds at and between humps. While local conditions L 2 HS = 0.50 (2.59 (V85) -656) Where Hs = the optimal spacing of humps (ft.), and Where V = the desired 85th percentile speed (m.p.h.1 1 85 be tween road humps. This equation is deemed valid for d range of from 16 m.p.h. t( m.p.h. Using this formula for a 4" high road hump, the optimal spa( for the 85th percentile speeds of 30 m.p.h. is 838 ft. and fo; m.p.h., it is 481 ft. A special Subcommittee of the California Traffic Control Dev Committee developed an approximate spacing equation for a 3" 1 speed hump from the speed data in Australian and Cnited Lint tests. This equation is as follows: ? Hs = .5(2(V85)--700) Where Hs = the optimal spacing between 3" humps (measured in feet), and Where V = the desired 85th percentile speed 85 be tween humps (in m. p. h. ) . The spacing for the 85th percentile speed of 30 m.p.h. calculated to be 550 ft., and for 25 m.p.h. is 175 ft. n n C Y 0 v 0 m 0 - 0 0, (Y 0 .m d 0 r r.n LCT uE -L Em m bno O* CI. .- 0 a2 -0 II 4 !; cc '* ' 0 -0 h ' < - 0 ou -0 LL 4 u 2 0- n - on0 -0 mc r: e= -.I L 3- L- .nu 0 .- u -0 a L ca - Y - 3 or L- 4- La ma a* -a= E" V 0- -0 L 2:: P n C Q 0 -0 0 nrr (Y LC 9c YI QQ .. vu nn 00 ma a 3- LL 4.7 '0 -0 - 2 1 a -15- 0 -- *. . ,- A series of two or more speed humps are usually more effect than single hump installations. Any one series of humps sho generally not be greater than one-half mile in length and the of one series should not be -immediately adjacent to anot series. Speed humps may also be used in pairs to increase th effectiveness. When installed in pairs humps are generally closer than 10 feet and no further apart than 40 feet. T should ideally be located adjacent to property lines as oppo to the center of a property in order to minimize residen aesthetic concerns. The first hump in a series should normally be located ii position where it cannot be approached at high speed from eit direction. To achieve this objective speed humps (at the fi hump in a system) are typically installed within approximat 100 feet or less of a small-radius curve or stop sign, or at top of a hill if installed on a street with signific downgrade. FHWA Report No. FHWA/RD-81/031, Improving Residential Street Environment, offers the following guideli for determining the number and placement of humps for vari street segment lengths: 1. Single short blocks (less than 400 ft.) with SF control problems are unusual. Where such blocks n be treated, a single hump positioned near mid-bl would likelv provide satisfactorv speed control c the entire block. 2. Where control is required on single block segments moderate length, a two hump configuration should satisfactory. 3. On very long blocks, 3 or more humps may be necessai 4. On lengthy continuous segments or on control segmf comprised of a number of blocks, it appears desir: to space interior humps bOO to 600 ft. apcrt, altiic spacings up to 750 ft. apart mav be satisfactory. least one hump should be placed in each block c7 control segment. Figure 4.4 illustrates these hump spacing concepts. .. 0 -17- e _- 4.03 Traffic Control Traffic control consisting of signs, markings and poss: flashing signals is essential to warn roadway users of a SI hump's presence and guide their subsequent action. While minimum standards exist for devices to be used in conjunci with speed humps , devices typically used by agencies include following: Traffic Signs - The most common warning sign used appl to be the standard MUTCD W8-1 "BUMP" warning sign. W1 the MUTCD does allow special warning signs for non-stant situations, most agencies have found the "BUMP" sign tc appropriate for use with speed humps. The sign typically installed in advance of the hump and at the although some agencies install only one or the ot Advance warning signs should be located based on H Table 11-1, "A Guide for Advance Warning Sign Place Distance." Some agencies also require installation o advisory speed plate indicating the recommended cros speed at the hump. Advisory speed plates are considered useful in educating unfamiliar roadway user the recommended crossing speed when humps are initi installed. Some agencies install a special supplemental p of street segment. These signs typically carry the le "Next XX Feet" and are installed under the first hump preceding a series of humps. Side road approaches intersect a street within a series of humps should als evaluated with regard to the need for advanced notifica signing. Some agencies install warning signs supplemental arrow plates indicating the location of s humps on an intersecting street. In certain instances it may also be justified to ins special attention flags or flashing lights to speed warning signs. These devices are sometimes used in initial installation period or in locations where urii combinations of roadway or vehicle operating condi present special conditions that warrant additional wa devices. I indicating multiple humps are in place for a certain le Markings - ?tarkings in use by agencies today in1 advance word messages (typically "BUNP") and spl markings directly in advance of or on the hump. Se? hump marking designs are in use today, but the d' selected should not create confusion with sta crosswalk markings unless the hump location is intende pedestrian crossings. Pavement word and symbol mar should be white in color as required by the MUTCD. I 0 -18- a -. .I Some agencies have installed double yellow center1 markings to call additional attention to hump locations to prohibit passing in the vicinity of the hump, and ot agencies have installed reflective markers in advance of at the hump to improve nighttime visibility. Figures 4.5 and 4.6 illustrate a number of signing and mark designs in use by agencies today. Any agency installing SF humps should review their State and Federal Manual on Unif Traffic Control Devices for minimum requirements bef establishing typical speed hump signing and marking designs their jurisdiction. 4.04 Installation Angle Speed humps should be installed at a right angle to centerline tangent of the roadway. 4.05 Drainage and Utilities Speed humps should be installed with appropriate provisions I for roadway drainage and utility access. Humps should gener; not be located over or contain maintenance access holes, 01: located adjacent to fire hydrants. Ideally a hump should be installed at a location immediatei; the downside of an existing drain inlet. If this is not feas the construction of a bypass drain or other treatment to rl water around the hump should be considered. 4.06 Roadway Edge Treatments On roadways with barrier curbs, humps should ideally extend f across the road from curb to curb. If tapering is necessary drainage or other reasons, the edge taper should be accompli at an angle that will not affect the downstroke of bicvcle pe or subject vehicles to undercarriage damage. A phenomenon known as "gutter running" may be encouraged tapered hump edges since drivers can drive with one wheel in gutter thereby reducing the humps' ability to slow vehicles. humps are installed with tapers, or used on non-curbed road\ raised pavement markers, delineator posts, or other treatn should be considered to eliminate or reduce the possibilit vehicles attempting to partially or totally avoid the hump. should be recognized, however, that these devices may h3v impact on maintenance and snow removal activities. If inst2 on roadways with paved shoulders, the hump should ideally e? across the shoulder in order to discourage vehicles attempting to avoid the hump. Figure 4.7 illustrates techniques for providing hump tapers edge treatments on non-curbed roads. -1Y- a &MIMG FLAGS [FIRST WEEK) -- ="x ma w3-72 WARflIffi 3GM BLACK CW YELLOW, ,, b'SsU71l3 E LETTERS W6(15) SlGM MPU S\rJN LOCATICNS aS DIizECTEC EY EhJGihlEEG L- -1 - 0 Humps for '2 mile Pz Humps for 300 yards SI I Hump20 yds Ll d a -20- 0, -- -, L 10" reflective white stripes Installed by City forces y EOGE OF PAVEMENT EXISTING GUTTER b CURE - 1 SIDEWALK I ~MOVUIFYunGS10= WWTE wm wiu mTWn Figurc 4.6 W -21- *- _I A.C. STANOAAO VARI€S COAT CUR8 :T=+++ FACE m I %H7 bahind Figure 4.7 0 -22- 0 .- *- 4.07 Coordination with Street Geometry A thorough on-site analysis of roadway geometrics should performed to ensure that speed humps will not be introduced a critical point in the roadway system, i.e., a severe combinat of horizontal and vertical curvature and/or street gradient. 4.08 Coordination with Traffic Operations Speed humps should not be installed within 250 ft. of a traf signal- or within an intersection or driveway. This suggestior not intended to apply to the use of a raised intersection a valid traffic management technique. 4.09 On-S tree t Parking Care should be taken to ensure that vehicles parked on street: not diminish the effectiveness of the signing and marking speed humps. Should parking be removed adjacent or in advance the hump, the ability of vehicles to avoid tapered humps gutter-running'' will be enhanced. Each hump installation shc be evaluated independently for' site-specif ic par1 considerations. 17 4.10 Streetlighting To improve nighttime visibility, especially where sight dist is less than desirable, coordinating hump locations with exis or planned streetlighting should be considered. '4.11 Construction Materials The construction of the hump can be pre-cast concrete secti concrete cast in situ, asphalt or brick/concrete pav Experience has shown that the use of soft material will resul deformations as the top of the hump is puslied in the directio the t:raf f ic stream. 4-12 Construction Procedures It is recommended that a template be constructed to verify accuracy of the hump profile and to ensure that the de? dimeinsions are attained within reasonable tolerances (non one-half inch or less provided that the hump does not excf inches). If the profile is incorrect, hump characteristics be changed which may result in vehicle damage or ineffec speed control. IF the hump is constructed in situ, it is recommended that road surface be excavated at tapering edges to prevent spa h 4 \ Segment of circle 0 Sm Radius * 54.22 ft. P 7 e -24- 0 -d '. _- 5.03 Volume Studies Traffic volume counts should be made on the subject street and those other streets where traffic diversion may be expect( These counts should be made before installation and after trafl patterns have stabilized to determine the magnitude and specii location of this diversion. Both turning movement and 24-hour volume counts may be needed quantify these impacts. 5.04 Stop Sign Obedience Studies may be desirable before and after hump installation determine if the speed humps have impacted the compliance rate affected stop sign locations. Increased violation rates shc be considered in speed hump evaluations and selective enforce5 may be necessary to address the problem. 5.05 Travel Time Studies Based on the particular requirements bf the installation, it be desirable to perform detailed travel time studies before after hump installation to determine the effect on overall tr; time along the subject street or through the area. 5.06 Accident Analysis A thorough before and after accident analysis should be perfo to determine if accident trends have been noticeably impactec the speed hump installation. It may be necessary to estab ongoing analyses at some locations to gauge the longer- trends of accident rates. 5-07 Resident and Driver Surveys Within 30 to 60 days after installation (or at the end of established trial period) it may he desirable to survey adja residents and other affected residential areas to assess t concerns and perception of the speed humps' performs Motorists continuing to travel the street may also be selecti surveyed to assess their opinion of the speed humps' insts tion. Emergency and service agencies should also be offered opportunity to comment on the installation. 5.08 Noise Analysis It may be desirable to perform both before and after studit determine the speed hump's impact on traffic noise in advanc at, and beyond each hump site. w -25- _I _.. - ,- 5.09 Vibration Analysis It may be desirable to perform vibration analysis to determine roadway vibrations transmitted by the hump crossings are expec to have detrimental effects on adjacent properties structures. 5.10 Pedestrian, Bicycle, and Social Activity Before and after observations may be made at various times of day and night to determine if pedestrian, bicycle, and ot types of resident activity have been altered as a result of speed hump installation. 5.11 User Cost Analysis It may be desirable to perform a detailed "beforelafter" cost analysis considering vehicle speeds, travel times , veh and driver costs, and other elements. This analysis shoulc based on the particular characteristics of the speed hump sy and other residential traffic management techniques b employed . I 5.12 Vehicle Emission Analysis It may be desirable to perform a vehicle emissions analysi determine the speed hump's impact on air quality. This anal will require both before and after studies of traffic vol~ acceleration/deceleration, and speeds. 6.00 OTHER CONSIDERATIONS 6.01 Liability Concerns Speed humps and other pavement undulations are not tr, control devices as defined by the Manual on Uniform Tr, Control Devices. They are, however, geometric design featuri the roadway and should be designed, installed, operated, engineering judgment. If speed humps are not installed in a proper manner and wit care, and vehicle damage or personal injury occurs, i possible that the installing agency could be found t maintaining a public nuisance, i.e., a known defect in the s system which may result in increased liability expc Therefore , complete and proper documents should be retain justify the decisions made. Local and state laws should a1 reviewed to identify any regulations pertaining to rc design, roadway maintenance, traffic control, or other elf that may be related to the use of speed humps or other georr design features. maintained using accepted engineering principles and pr e -26- 0 .- <. 6.02 Vehicle and Cargo Damage Where streets with speed humps are expected to carry substant numbers of long wheel-base vehicles or other special vehi types such as motorcycles and bicycles, a special attempt sho be made to warn and notify drivers of these vehicles that sp humps exist and how they should be driven to minimize proble It may also be desirable to modify the standard hump design further minimize impacts to these users. 6.03 Coordination with Pedestrian Crossings If mid-block pedestrian crossings exist or are planned, it may desirable to coordinate them with speed humps since vehi speeds will generally be lowest at speed hump crossings. fact, it may be desirable to install a hump directly adjacent or on the pedestrian crossing. Pedestrian access can encouraged by paving any grassed area connecting the hump nearby sidewalks. In addition to standard signing, pedestr crossing signs should be installed for any established crossin 6.04 Aesthetic Considerations I It is possible that speed humps can be constructed of spec materials such as brick pavers or specially-treated concrete order to enhance their appearance. However, consideration sho be given to street maintenance requirements in the area whether or not special materials can be properly maintained the responsible agency. 6.05 Incorporation in New Street Design It is desirable in the planning of new residential subdivisi to configure and design local streets to minimize excess speed, excessive volumes, and cut-through traffic from out5 the immediate neighborhood. However, where adequzte subdivis planning and street design has not or can not he achieved, one of the aforementioned problems is considered likelv, it be appropriate to include speed humps as a part of new stt construction after consideration of less restrictive design traffic control techniques. Adequate signs, markings, and ot devices should also be provided to support their installation. 6.06 Enforcement Needs During the initial stages of speed hump experience, it 1 generally be desirable to employ special police assignment enforce traffic violations occurring at or near speed humps along routes experiencing diversion. 0 -27- 0 -* .- 9 6.07 Maintenance Issues Care should be taken in the initial installation and monitori of speed humps to ensure that edge ravelling and profi deformation does not exceed established tolerances. Regular scheduled inspections and maintenance should be performed maintain the appropriate design relationship between the hump a the street so the hump continues to perform its intended purpc within allowable tolerances. If pavement maintenance activiti result in speed hump markings being reduced or eliminated, tf should be promptly replaced or supplemented with temporary sig providing the same warning to motorists. While damage from snow plowing activities was initially a concl in speed- hump installation, experience has shown that humps generally not a detriment to those activities provided that hump edges are properly maintained. t - -- 1 Bar-Ziv, y., zaide1, nd Hakkert. A-S.. "Traffic Rest' Technion city w Means of Speed Reducing Devic Markers.*' Transportation Research Institute* Road Wichita* Kansas Long, Todd hey. The Use of Traffic Control He s in the Prevention of Throu h Traffic Movement on Residential Streets. Hasters Thesis. gGeorgia Institute of Technology, civil Engineering j -- . -Department, September 1990. Haifa, Israel. 1986- ~ - city Of Dallas. Texas, Speed Hump Policy and Installation Procedures on , City of Wichita, Speed Bump'Hump Studyo of operations and Maintenance. 19B6* Of ~ 1 Residential Streets (Preliminary Report), Department Transportation. Dallas, Texas, July 1990. England and Wales Gove-nt Statute No. 1856, The High* Gorman. Uichael N.. et. al., "Evaluation of Speed Hump Program in the Humps) Regulations 1986. London. England, 1986. ! City of Dmaha." ITE Journal, June 1989, pp. 28-32. Institute of Transportation Engineers. Technical Council 5B-15, Technical Council InfOnriatiOn I Bumps-Appropriate for Use on Public Street .I' 2 Zaidel. D.. Hakkert, A.S.. and Pistiner. A.H.. A Critical Evaluation of the Use of Humps in Urban Areas. Insistute, Technion-Israel Institute of Technology, Haifa, Transportation Research 56, No. 11, pp. 18-21. 1986. Israel, July 1989, Uak. K.K., "A Further Note on Undulation as a Speed Con1 Transportation Research Record 1069, Traffic Cont Rail-Highway Crossings. T.R.B., D.C.. 1986. Petcersson. H.E.. "Rumble StKipS." National Swedish RO. Research Institute, Report No. 890, 1986 (in Swed Road Traffic Authority, Guidelines for the Use and Inst Homburger. Wolfgang S., Elizabeth A. Deakin, et. al., Residential Street Design and Traffic Control. Washington, D.C.. Institute of Transportation Engineers, 1989. ~umps. Victoria, Australia, 1986. I Tako, Michael J.. "Long-Term Study of Speed Humps in Tampa, Florida." City of Tampa Transportation Department, Florida. March 1988. City of Portland, Oregon, Neighborhood Traffic Manaeenenc Program. Porclahd Office of Transportation, April 1988. Stephens, B.W.. "Road Humps for the Control of Vehicul: Traffic Flow." Federal Highway Administration, Public Roads, Vol. 50, No. 3, pp. 82-90. 1986. Hanchey, C.H. and Myer, S.E., "Local Traffic Engineering: Where are We." I.T.E. Journal. pp. 27-31. May 1988. Wuerz, Donald E.. "Speed Humps." Letter to the Editor, Civil - Zaidel, D.. Hakkert. S.A., and Barkan. R., "RwbIe StKl Engineering, July 1988. Strips ac a Rural Intersection." Transportation 1069. Traffic Control Devices and Rail-Highway CI Chadda. H.S.. and Cross. S.E.. "Speed (Road) Bumps: I: opinions ." American Society of Civil Engine Nevnham, Donald F.. "Speed HumpsfFinal Report .I' a memorandum to the Altamonte Springs City Manager. Altanonte Springs, Florida. September 23. 1988. City of Pasadena. California, Evaluation of Tvo-Inch Hieh Experimental Transporration, Vol. 111, No. 4. Jul! Speed Humps on Wilson Avenue Between Orange Grove Dlvd. and Meier, Diane. The Policy Adopted in Arlington County. ' Washington Blvd. Department of Public Works and Transportation. Solving Real and Perceived Speeding Problems Pasadena. California. Xovember 1988. Streets. Paper presented at 55ch Annual I' Orleans. LR., August 1985. and Procedures. Department of Public h'orks. Appleton, Wisconsin. 1988. City of Appleton. Wisconsin. Speed Hump Warrants; Speed iiump Polic~rs Hakkert, A.S.. Zaidel, D., and Bar-Ziv, T.. "Speed Hun1 Roads." Report 85-81. Technion-Israel Insticut Transportacion Research Institute, 1985 (in Hebr' Hashirnoto. K.. Nishirnuro, H., Taterna. Y.. and Fujicsuka. T., "Assessing the Effectiveness of the General Traffic Safety Yodel Scheme." 1988 <in Japanese). pivnik. Sheldon I., "Xeighborhood Speed Control I.iJbil National Association of Australian State Road Authorities. Guide to Transportation Research Board. Washingcon. D Consideracions." a paper presenced at the Annu. 1984. - ' Traffic Engineering Practice: Part IO--Local Area Traffic 2 Hanagement. Sydney AuStKillin, 1988. TRB Session 126, "Neighborhood Speed Control - A Syntl Hump Experience." January 1984. City of Sacramento. California. "Policies and Procedures for the Installation of Undulations." Internal Circular. September 8. 1987. Informal Report Number 84-05-02, "Speed Bump Survey ..' Himmar 5. Chadda. Ph.D:, P.E. Washingcon. D Public Works. May 1984. Uynne. G.G.. "European Speed and Traffic Control Deveiopment." C Journal, pp. 43-44. September 1987. Inouye, Martin R., "SacrJmento County Neighborhood SPI City of Bellevue. Washington. Neighborhood Traffic Control Study." Western KTE. Vol. XXXVII. No. 3. June Program-Speed Hump Installation and Removal Criteria. Public Works Department, City of Bellevue. Washington, 1987. Humps. Public Works and Transportation Department, Pn:adena. ~ California. 1987. Rezek, J-. "Rmbl. Strips." Alaa~. hpar-mt of 'h Facilities. Research Notes Vol. 4. NO. 5, N~~~~ hePerican Ahsociation of State Highway and ==ansportar Policy on Geometric Design of Highuaya and str D.C.. 1984. De wit. T.. and Slop. U.. "Traffic Humps as Rec-enc Study Centre for Traffic ~~~i~~~ City of Pasadena. Californfa. Policies for the Installation of S eed Department of Transport. london. Traffic Advisory Unit Leaflet 3/87, "Speed Control Humps." Traffic Policy Division. London, 1987. and Effects." PTRC Annual Ueeting PKOC.. 1984. U.K. The Institution of Highways and Transportation vith the Department ! of Transport, "Roads and Traffic in Urban Areas." 1987. GovaertS, u-. "Evaluation of Speed Humps in Lewen." Vola 35, NO. 11, 1984 (in Dutch). Zebaurers, Valdis, "Speed Control Bumps in Jefferson County." Highways , and Transportation Department, Jefferson County. Colorado, 19e7. Hi€XinSs J-s-, Barbel. W. (Federal Hfghvay Administr. Department of Transportation), "Rumble Strip Institute of Transportation Engineers. Rec-ended c, City of Phoenix, Arizona. "Experimental Tests vith Speed Humps in 1984. Phoenix: Final Report." Depaitment of Screets and Traffic, City of Phoenix, Arizona. January 1986. Subdivision Streets--A Recornended practice. 1984. Janris, J.R., "Concrolled Testing of 'Flat-Topped Road Humps','' Internal Report Australian Road AIR 853-2. Research Board. Victoria. Australia. September 1986. Zaidel. D- et dl.. "An Experimental Comparison of pa. Rumble Strips at Lou-Volume Rural Intersectio Annual Meeting Procedings. 1984. Xinistry of Transport - Traffic Division, "Speed Restraining Devices on Yosef Ban-Iaari Street in Jerusalem - Before and After Stud?.." City of Jerusalem, October 1986 (in Hebrev). C1ement. J-p-. "Speed Humps and the Thousand Oaks h, ITE Technical Council Committee 58-15, "Road Bumps--Appropriate for lke on Public Streets?," ITE Journal, November 1986, pp. 18-?I. vereniging het Nederlandsche Uegencongres, "Study of Stevens, Burton U., "Road Humps for the Concrol of 'Jehicular Speeds and Traffic Flow." Public Roads, December 1986. pp. 82-90. in Hewelo: Advantages and Disadvantages." w 1. Netherlands. January 1983 (in Dutch). Journal. January 1983. pp. 35-39. U.K. Department of Transport, "Road Humps." Joint Circular 8/86 (Iondon) and 52/86 (Welsh). December 1986 Link, 0.9 Meiron, 0.8 Hakkert, A.S., and Zaidel, D., "Speed Restraining ' DeviceS - CriCeria for Installation Guidelines Proposal - psrt A*" MinistrY of Transport - Traffic Division. July 1983 (in Hebrev). Jarvis, J.R., Sveatman, P.F.. "The Loading Of Pavements j of Road Humps." ARRB Proceedings of the 11th Conf rhe University of Melbourne. Vol. 11. part 2. 1982. Jivatode, R., and Burke, T., ,,Neighborhood Speed Control Project." D.C. Department of Transportation Caarder. f-. "Bus Traffic and Road Kunrps." hnd ~~~~i~~~~ of Technology, University of Lund, Sweden, August 1982, Washington. D.C.. 1980. ''Lynne, George, Traffic Restraints in Residential Neighborhoods. I . Transition, Inc., New Brunswick. New Jersey, 1980. 1977. 0 -. z W *.. 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