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HomeMy WebLinkAbout7.1 DonohueDrSpdStdyCITY OF DUBLIN AGENDA STATS~iENT City Council Meeting Date: September 8, 1986 SUBJECT: Donohue Drive Traffic Study (Continued from Previous Meeting) EXHIBITS ATTACHED: RECOMMENDATION: 1) 2) 3) 1) 2) 3) Report from TJKM dated October 14, 1985 Minutes of October 14, 1985, City Council Meeting Report from Dublin Police Services Notice Sent to Residents Review report Receive public input Deliberate and determine whether further improvements are warranted. FINANCIAL STATEMENT: None at this time. DESCRIPTION: ~ ~ At its~meeting of Augus~ 25, 1986, the City Councilzreviewed the report submitted by TJKM in October of 1985 regarding speeding problems on Donohue Drive and Landale Avenue. This report did not recommend installation of STOP signs at any of the three intersections studied (Donohue at Gardella, Donohue at Ironwood, and Landale at Vomac) but did suggest increased police enforcement of the speed limit and installation of reflective pavement markers along the double yellow stripe at the sharp curve near the Ironwood intersection. These pavement markers were not installed at the time because of objections to the noise created when motorists drive over them. An oral presentation by TJKM at the August 25th meeting indicated that the _pavement__ markers woul~ still be recommended. The City Council determined to continue their review of the report to the meeting of September 8th so that residents of the area would have an opportunity to comment on the proposed solutions. Notices regarding the meeting were mailed to residents of Donohue Drive, Landale Avenue, Ironwood Drive, Starward Drive, and Vomac Road on August 26th. Dublin Police Services has supplied the following information regarding citations, accidents, and prevailing speeds observed since October of 1985: A total of 71 citations were issued for moving violations. Ten collisions occurred during this time, one of which involved an injury. A review of the citations indicates that the estimated prevailing speed would be 25 to 35 m.p.h., with the additional comment that peak period speeds would tend to be lower and off-peak speeds would tend to be higher. Dublin Police Services' recommendation is concurrent with TJKM's regarding "consistent, repetitive, and obvious enforcement by patrol officers." ITEM NO.~~ COPIES TO: TJKM Dublin Police Services MEMORANDUM 4637 Chabot Drive, Suite 214 Pleasanton Ca. 94566 (415) 463-0611 TO: FROM: SUBJECT: Lee Thompson, City Engineer City of Dublin Chris D. Kinzel, Principal TJKM Donohue Drive/Landale Avenue Speed Study We have completed an investigation of requests made by Dublin residents concerning the speeding problem on Donohue Drive and Landale Avenue. As part of our investigations we measured the prevailing speeds on Donohue Drive and on Landale Avenue using radar from unmarked vehicles. We obtained 24-hour traffic counts and turning movement counts during the a.m. and p.m. peak traffic periods. We reviewed the history of reported accidents and discussed with the Police Department their experience with citations on Donohue Drive and Landale Avenue. Finally, we made several field surveys of the' area in order to observe problems and possible solutions. Existing ConJitions Donohue Drive is a two-lane curving residential street which extends north from Amad, or Valley Boulevard to Ironwood Drive where it curves west and becomes~Landale Avenue. Landale Avenue is also two lanes and becomes Starwaf~' Drive. Landale Avenue intersects with Vomac Road, providing access to San Ramon Road via Shannon Avenue or Vomac Road. (See Figure 1.) The entire length of Donohue Drive and Landale Avenue is fronted by single family residences, except for a fire station and some apartments on Donohue Drive just north of Amador Valley Boulevard. Pa'rking is permitted on both sides of the street. During the day many vehicles including some large vehicles such as campers and trailers park along the street. A double yellow no-passing stripe is painted the entire length of Donohue Drive and Landale Avenue. The speed limit is 25 mph and signs are posted on Donohue Drive at Hillrose Drive and on Starwa4Kd Drive near Oxbow Lane. Prevailing Speeds In order to measure the severity of the speeding problem identified by the residents, we conducted radar speed surveys at two locations. The first location was on Donohue Drive approximately 500 feet north of Irving Way. Speeds were measured during both the a.m. and p.m. peak traffic periods. During the a.m. period, most southbound vehicles were in the 28-37 mph range and most northbound vehicles in the 25-34 mph range. During the p.m. period, most southbound vehicles were in the 27-36-mph-range~ with mo~t' northbound vehicles in the 28-37 mph range. PLEASANTON ' SACRAMENTO ' FRESNO · CONCORD Lee Thompson -2- Of the vehicles Obsewved speeding excessively (£aY 'over 38 mph) the make-up of the drivers ranged the whole gamut, from young people to mothers with two to three children in the car. The second location was on Landale Avenue east of Vomac Road. At this location, speeds were measured during the p.m. peak period. The speeds were generally lower because the majority of the traffic was turning at Vomac Road. Westbound, the majority of vehicles were in the 21 to 30 mph range westbound and 19 to 28 mph eastbound. A summary of the radar Speed surveys is as follows: Vehicles Location Direction Observed 50th 85th Percentile Percentile 7:30-8:30 A.M. Donohue Dr. 500' N. of Irving Donohue Dr. 500' N. of Irving Northbound 30 28 mph 34 mph Southbound 50 33 mph 37 mph 4:15-5:00 P.M. Donohue Dr. 500' N. of Irving Donohue Dr. 500' N. of Irving Northbound 99 33 mph 37 mph Southbound 76 31 mph 37 mph 4:00-5:15 P.M. Landale A~e. 150' E. of Vomac Eastbound 29 25 mph 30 mph Landale'~ve. 150' E. of Vomac Westbound 29 25 mph 30 mph The 85th percentile speed is that speed at or below which 85 percent of the observed vehicles are travelling. It is a well recognized fact among traffic engineers that most drivers are able to drive at reasonable speeds without the benefit of any speed limits, speed signs, or enforcement. The behavior of traffic is a good indication of the appropriate speed zone which should apply on a particular highway section. It is generally felt that at least 85 percent of the drivers operate at speeds which are reasonable and prudent for the conditions pertaining in each situation. Therefore, the 85th percentile speed of a spot speed survey is the primary indicator of a speed limit which might be imposed subject to the secondary factors of accident experience, traffic volumes, road features or other special situations. The 85th percentile speed on Donohue Drive southbound was 34 mph in the morning and 37 mph in the afternoon, on Donohue Drive northbound 37 mph, on Landale Avenue 30 mph. Although these speeds indicate that a speed limit higher than the posted 25 mph speed limit might be appropriate, we do not recommend raising the speed limit. The existing 25 mph speed limit is appropriate for Donohue Drive and Landale Avenue because they are local, residential streets. Lee Thompson -3- Traffic Counts Traffic was counted at three intersections during the a.m. and p.m. peak periods: Vomac Road and Landale Avenue, Donohue Drive and Ironwood Drive, Donohue Drive and Gardella Drive. Figures 2 and 3 present a summary of the intersection counts. A 24-hour count was made on Donohue Drive between Irving Way and Ironwood Drive. A total of 1,608 vehicles were counted on Donohue Drive, 767 northbound and 841 southbound. (See Table I) These counts show very. light traffic with the majority of traffic proceeding along Donohue to Landale then turning onto Vomac or the reverse movement Vomac to Landale to Donohue. It was noted during these counts that many right-turning vehicles do not stop at the STOP sign on Vomac at Landale. Some of this traffic may be "through traffic," vehicles shortcutting through the area to avoid the congestion on San Ramon Road and on Amador Valley Boulevard. Accident History The accident history on Donohue/Landale shows two non-injury accidents in 1983, two non-injury in 1984, and two non-injury in 1985. None of these happened during peak hour traffic. Of these six total accidents, three and possibly four of them involved drunk drivers. Details of the accidents are summarized on Table II. Citation Experience The Police Department reports that very few citations are given on Donohue Drive o~-Landale Avenue. According to the Police Department, because of limited resources, they concentrate their enforcement efforts on the major streets where they can have the most impact and be more visible to many more drivers. In the past when they have attempted to enforce speeding in this area they have given only about one ticket in an eight hour period. This is because the traffic volumes are relatively low. Many drivers that we, in an unmarked vehicle, observe speeding slow down when they see a police car. So few citations are issued. However, if drivers are slowing down because of the presence of a police car, then the enforcement effort should be considered effective, even though few citations are issued. Field Review We observed the area at several times of day. During the morning hours, traffic is very light and speeding is not a noticeable problem. During the afternoon, traffic is somewhat heavier though still very light, averaging two to three vehicles per minute. An occasional vehicle is speeding noticeably. Lee Thompson -4- . :.. :., The existing traffic signs and markings are in 9ood condition, except the double yellow-stripe--loolc~-aqqttqe--dull.--Approxi'mately-50--pe¥cent of'th~ vehicles, including many that are not noticeably speeding, cross over the double yellow stripe in the vicinity of Gardella Drive and Hillrose Drive where Donohue Drive is somewhat curvy. Some vehicles cross the line even on the straight portion of Donohue Drive from north of Irving Way to Ironwood Drive. Petition of Residents Residents have requested additional STOP signs be installed to stop traffic on Donohue Drive and Landale Avenue. Specifically, STOP signs have been requested on Donohue Drive at Gardella Drive, on Donohue Drive at Ironwood Drive, and on Landale Avenue at Vomac Road. The intended purpose of the STOP signs would be to reduce the prevailing traffic speeds. However, studies have shown that STOP signs used for speed control do not reduce speeds, and sometimes increase speeds, except in the immediate vicinity of the signs. A good example of a similar situation where STOP signs were ineffective for speed control is Davona Drive in Dublin. In 1982, the City Council authorized STOP signs at two intersections along Davona Drive. Since their installation, there continue to be complaints of speeding. Over the years, traffic engineers have ~oted that the use of STOP signs for speed control is ineffective. Motorists tend to roll through unwarranted STOP signs and then make up for lost time by going even faster. In the case of Davona Drive we have not made STOP sign compliance checks, but drivers'are' violating the STOP signs because on most occasions there is no vehicle or pedestrian traffic to stop for. In our most recent radar checks we have. noted that speeds have not reduced since the placement of the STOP signs. } We made a total of 12 radar checks at different times and locations along/ Davona Drive and found that the average speed is still about 30 mph and the/ speed driven at or below by 85 percent of the motorists is still aboul~ 35 mph. //For Donohue Drive, speeds on the straight portion with perhaps the highes'~g~ J prevailing speeds, would remain the same or increase if the STOP signs were/ x,~ installed. STOP signs at Gardella Drive and at Ironwood Drive would b~ ~requently violated because there is practically no side street traffic ~or w~ich the Donohue Drive traffic needs to stop. At Landale Avenue - Vomac Road the traffic volumes are more evenly divided among the approaches and the volumes are higher than at Gardella Drive or Ironwood Drive. However, a STOP sign at this location will have no effect on speeds along Landale Avenue or Donohue Drive. Over 90 percent of the traffic entering this intersection is making a turn and so is already slowing. The residents also have requested WATCH FOR CHILDREN signs on Donohue Drive near Hillrose Drive and near Gardella Drive, on Landale Avenue near Sunwood Drive and on Sunwood Drive near Gardella Drive. WATCH FOR CHILDREN signs are not an official traffic control device. They are ineffective because virtually every residential and many non-residential streets, could have them. They may, in fact, be counterproductive by encouraging children to play in the street, feeling they are protected by the signs. Lee Thompson -5- Recoa~endations We have studied the suggestions of the residents to install additional STOP signs and WATCH FOR CHILDREN signs on Donohue Drive and Landale Avenue. We do not recommend either approach. STOP signs used for speed control are ineffective. Rather, multi-way STOP signs are installed to assign the right-of-way at intersections with heavier traffic volumes than we have here or to correct a serious problem with intersection accidents. WATCH FOR CHILDREN signs are ineffective at best and may create less safe conditions by encouraging children to play in the street. Our recommendations are: Increase police enforcement in the area, especially in the afternoon peak period and later at night when some of the drunk driving accidents have occurred. Enforcement should include speeding and STOP sign violations. The area should include Starward Drive and Vomac Road as well as Donohue Drive and Landale Avenue. Repaint the double yellow stripe on Donohue Drive and Landale Avenue. ~ Install raised reflective pavement markers along the outer edge of the / existing double yellow stripe. This will effectively narrow the lane/ and give a warning to drivers going too fast for the curves. The sound and feeling of running over the markers should cause some inattentive drivers to slow down. The raised markers have two disadvantages which should be mentioned. They may increase noise levels for the residents as vehicles run over them. By effectively narrowing the road, they may increase the likelihood of drivers hitting parked cars. If the residents have no serious objections to these potential disadvantages, we recommend installing the raised markers. At the very least, the existing double yellow stripe should be repainted. psw Enclosures 15725 TABLE I 2~, HOUR TRAFFIC COUNT AGENCY: LOCATION: TYPE OF COUNT: Dublin Donohue Drive between Irving Way and Ironwood Drive Directional Northbound Day Monday Tuesday Date 6/17/85 6/18/85 12-1 A.M. - 7 1-2 A.M. - 5 2-3 A.M. - 1 3-4 A.M. - 2 4-5 A.M. - 1 5-6 A.M. - 6 6-7 A.M. - 12 7-8 A.M. - 24 8-9 A.M. - 27 9-10 A.M. - - 25 10-11 A.M. - 26 11-12 A.M. - 39 12-1 P.M. - 37 1-2 P.M: - 46 2-3 P.~. - 54 3-4 P.M. 51 4-5 P.M. 70 - 5-6 P.M. 93 - 6-7 P.M. 69 - 7-8 P.M. 47 - 8-9 P.M. 42 - 9-10 P.M. 45 - 10-11 P.M. 23 - 11-12 P.M. 15 - A.M. Peak 11-12 39 P.M. Peak 5-6 .93 - TOTAL 404 363 Southbound Ronday 6/17/85 Tuesday 6/18/85 - 8 - 6 - 3 - 0 - 4 - 15 - 25 - 60 - 37 - 29 - 38 - 35 55 7O 65 66 38 40 18 13 5-6 70 64 48 49 55 365 7-8 60 476 ADT 767 TOTAL ADT ........................ 1,608 841 TABLE II DONOHUE DRIVE/LANDALE AVENUE ACCIDENTS Location Hillrose at Donohue Donohue Drive 30' N/O Irving Way 1983 Type of Accident Non Injury, 2-Vehicle, Head-On Non Injury, 2-Vehicle, Backing Time 12:10 P.M. 3:10 P.M. Cause Inattention Inattention Donohue at Hillrose Irving 40' East of Donohue 1984 Non Injury, 2-Vehicle, Hit Parked Car Non Injury, Hit Parked Car After being chased by patrol- man, speeds as high as 55 were attained on Landale/Donohue. 1:00 P.M. 3:20 A.M. Drunk Drunk Donohue Drive 40' S/O Irving Donohue Driv~6' S/O Irving 1985 Non Injury, .2-Vehicle, Sideswipe Non Injury, Hit Parked Car Probably speeding according to report. 9:50 P.M. 1:50 A.M. Drunk, Speeding Possible Drunk DONOHUE DRIVE AND LANDALE AVENUE EXISTING C'ONDITIONS ~~ FIGURE 1 T]qANSPORTATION CON$1Ut. TAN TS ~/0 ~ ,~ .., 9 Ix'a'" 7:30- 8:30 ~.M. _ . DONOHUE_DRIV~E AND LANDALE. AVENUE ..... .- A.M. PEAK HOUR ~~ FIGURE TRAFFIC COUNTS ~r--~ 2 TRAN~PORTA?ION ~ON~ANT~ 4:30 - 5:30 ~.M. DONOHUE .DRIVE _AND. LANDALE AVENUE P.M. PEAK HOUR ~~ FIGURE TRAFFIC COUNTS ~ 3 T~ANS~ORTATION COmbaTANTS in order to improve sight distance for cars leaving their driveway. Red curbing is requested on both'sides of the driveway. Staff concurs with this request for a sight distance problem on a slight curve in the street. This parking restriction will improve sight distance and facilitate right and left turns out of the driveway. A total of two on-street parking spaces, one on either side of the driveway would be removed. No public comments were made. Mayor Snyder closed the public hearing. On motion of Cm. Hegarty, seconded by Cm. Moffatt, and by unanimous vote, the Council waived the reading and adopted ORDINANCE NO. 27 - 85 ESTABLISHING TRAFFIC REGULATIONS (NO PARKING ZONES - REGIONAL STREET) SPEED STUDY DONAHUE DRIVE/LANDALE AVENUE TJKM, the City's Traffic Engineering firm was directed to study requests by residents related to speeding on Donohue Drive and Landale Avenue. The scope of the study covers existing conditions, prevailing speeds, traffic counts, accident history,-citation experience, field review, petition of residents and recommendations. The residents of the area requested stop signs on DonohUe Drive and Landale Avenue. TJKM, however, points out that signs are ineffective for speed control. Residents also requested "Watch for Children" signs. TJKM states that "Watch for Children signs are ineffective, and may create less than safe conditions by encouraging children to play in the street." In discussing prevailing speeds TJKM states that: The 85th percentile speed on Donohue Drive southbound was 34 mph in the morning and 37 mph in the afternoon, on Donohue Drive northbound 37 mph, on Landale Avenue 30 mph. Although these speeds indicate that a speed limit higher than the posted 25 mph speed limit might be appropriate, we do not recommend raising the speed limit. The existing 25 mph speed limit is appropriate for Donohue Drive and Landale Avenue because they are local, residential streets. During the field review it was noted that about 50 percent of the vehicles cross over the double yellow stripe on the curved portion of Donohue Drive near Gardella Drive and Hillrose Drive. It was also found that some vehicles cross the center stripe on the straight portion of Donohue between Irving Way and Ironwood Drive. Staff recommendations were to increase police enforcement which includes speeding and stop sign violations; repaint the double yellow stripe on Donohue Drive and Landale Avenue in the same locations; and install raised reflective pavement markers along the outer edge of the existing double CM-4-219 October 14, 1985 R~gular Meeting '0 yellow stripe (if the residents don't object). There might be local objections for two reasons: 1) Noise levels are higher when cars run over the markers; and 2) The markers effectively narrow the road and may increase the likelihood of drivers hitting parked cars. ~JKM stated that the markers would "give a warning to drivers going too fast for the curves. The sound and feeling of running over the markers should cause some inattentive drivers to slow down". Staff has talked to Mrs. Mary Rogers, one of th~ residents who wanted to have a neighborhood meeting prior to this Council meeting. Ten copies of the traffic study were made available to her, as well as an offer of staff time to attend the meeting to explain the study and recommendations. Mr. Dean Cook, 7577 Landale Avenue reported to the Council that he has had several cars totaled in their front yard. Their neighbors also have had cars totaled. Mr. Cook felt that stop signs on Landale Avenue at Ironwood and at Sunwood would slow traffic. Mayor Snyder indicated that he was a strong advocate of Mr. Kinzel's recommendations. In the past, the Council has put up stop signs as a result of residents' requests and later the Traffic Engineer's analysis of the results were proven correct. The City spends a lot of money for the expert opinion of a Traffic Engineer,-and if that Engineer makes recommendations, they are based on his expertise and experience in the field. Cm. Moffatt felt that increased police patrol was needed, and perhaps the Council should look towar~ adding a traffic patrol officer during the next budget year. Radar enforcement was discussed, and Cm. Jeffery felt this to be a perfect area for utilization of radar. On motion of Cm. Jeffery, seconded by Cm. Moffatt, and by unanimous vote, Council authorized Staff to repaint the double yellow stripe on Donahue Drive / and Landale Avenue in the same locations and directed the Police DepartmentJ to increase enforcement in the area. Cm. Hegarty made a motion which was seconded by Cm. Vonheeer to place a stop sign at Ironwood Drive. This motion was defeated due to NO votes cast by Cm. Jeffery, Cm. Moffatt and Mayor Snyder. BART LIVERMORE-PLEASANTON EXTENSION STUDY SUPPLEMENTAL ANALYSIS Bay Area Rapid Transit District has released a report analyzing the extension possibilities for the extension from Pleasanton to Livermore. The analysis provides a review of the alternatives and BART has requested comments. The Council reviewed the report, indicating Dublin has already deferred comments pending Livermore's comments with regard to route. Dollar figures have not yet been presented. The Council expressed concern as to when BART Regular Meeting CM-4-220 October 14, 1985 ALAf4EDA COUNTY SHERIFF'S DEPARTJHENT From: To: Deputy, D. ATKINSON #618 Police Chief, J. SEVERINI ~.~ August 29, 1986 DONOHUE DRIVE/LANDALE AVENUE TRAFFIC STUDY Subiect: STATI STI C' INFORMATION Citations issued October 1985 to August 26, 1986 by month month moving parking driving under the influence October 1985 10 3 2 November 1985 32 i 0 December 1985 3 I 0 January 1986 10 I 0 February 1986 16 0 0 March 1986 6 - I 0 April 1986 5 8 0 May 1986 4 3 0 June 1986 1 2 0 July 1986 I 0 0 August 1986~ 3 2 0 Automobile collisions October 1985 to August 26, 1986 by month month number of collisions October 1986 1 November 1986 0 December 1986 0 injuries 0 auto type property damage only January 1986 2 0 February lg86 0 March 1986 i 0 April 1986 0 May 1986 2 0 June 1986 0 July 1986 2 0 August 1986 2 I auto - property damage only auto - property damage only auto - property damage only auto - property damage only 1. auto - property damage only 2. auto vs bicycle TOTAL CITATIONS ISSUED OCTOBER 1985 to AUGUST 26, 1986 TOTAL COLLISIONS 10 collisions, 1 injury 71 moving, 22 parking page 2 TRAFFIC SURVEY -- DONOHUE DRIVE/LANDALE AVENUE August 29, 1986 (continued') PREVAILING SPEED On February 25, 1985, Dublin City Ordinance 5-85 was adopted by the City of Dublin. This ordinance established, and declared speed limits for Dublin City streets. Section i (i) of this ordinance established a safe and prudent speed for Donohue Drive as 25 miles per hour. In establishing this ordinance, a comprehensive traffic engineering (speed limit - traffic regulation) survey was conducted and prepared by the JHK and Associates company (Emeryville, California). Their recommendation at that time was a posted, safe speed of 25 miles per hour for the Donohue Drive, Landale Avenue area. This speed recommendation was made by using radar comparision, (clocking of motor vehicles using radar), and an engineering survey of the traffic area (two lane, paved asphalt roadway, north/south direction, residential neighborhood, with uncontrolled access from residential driveways -- intersections controlled by stop signs) In review, the prevailing speed for this roadway would be 25 to 35 miles per hour. (estimate) This speed range is obtained by reviewing the citations issued for 22350 CVC (u'hsafe speed) for this roadway, reviewing the traffic engineering survey, and personal knowledge of traffic conditions in this area. The statistics obtained are somewhat misleading, however. The traffic survey establishes a safe speed "for normal traffic conditions". The normal flow of traffic is determined during "off peak" driving times. Speeds, and conditions during a~tive, commute hours, and during nightime hours are going to vary from this norm. Speeds during commute or active use hours should have a tendency to show traffic slower thamnormal, with the exception of the "in a hurry" type driver. Speeds during nightime hours, when traffic is less congested, and the roadway free of pedestrian traffic, bicycles, ect; will show an increase in normal traffic speed, and an increase of obvious violations of the posted speed. To control, and maintain what would be considered a "safe speed" for this roadway, (given the design, location, and traffic use) would only be accomplished by consistant, repetitive, and obvious enforcement by patrol officers. (ie: citations "slow people down") 19 ,._~i-- m. 8g CITY OFFICES 6500 DUBLIN BLVD. ADMINISTRATION B29-4600 BUILDING INSPECTION 829~)822 CITY COUNCIL 829-4600 CODE ENFORCEMENT 829~822 ENGINEERING 829-4927 FINANCE 829-6226 PLANNING 829-4916 PO LICE 829..0566 PUBLIC WORKS 829-4927 RECREATION 829-4932 CITY OF DUBLIN P.O. BOX 2340 DUBLIN. CALIFORNia 94568 August 26, 1986 Dear Resident, The City Council of the City of Dublin will be reviewing the Donohue Drive traffic study, which was conducted last fall, at its next regular meeting on September 8th. At the time the original study was made, the City's traffic engineering firm recommended an increase in police enforcement of the speed limit. They felt that stop signs were not warranted and might tend to increase speeding rather than slowing the traffic down. The City Council has requested a review of this study in order to determine whether additional measures might be taken in order to help curtail speeding on Donohue Drive. You are invited to participate in this meeting, which will be held in the Dublin Library meeting room, 7606 Amador ValXey Blvd., on Monday September 8th at 7:30 p.m. If you have any questions, please feel free to call the City of Dublin Engineering Department at 829-4927. City Engineer LST/gr