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HomeMy WebLinkAboutRPT 6 TRAFF SIG OPER'S 10-04-93AGENDA] REPORTS NO. 6 10-4-93 Com" '- Inter- DATE: OCTOBER 4, 1993 TO: WILLIAM A. HUSTON, CITY MANAGER FROM: PUBLIC WORKS DEPARTMENT/ENGINEERING DIVISION SUBJEC~ TRAFFIC CONCERNS REGARDING TRAFFIC SIGNAL OPERATIONS OF LEFT- TURN ARROW PHASING RECOMMENDATIONS: Pleasure of the City Council. FISCAL IMPACT: At this time, there is no fiscal impact to the City regarding the preparation of this report. BACKGROUND: At the September 7, 1993 City Council meeting, Mayor Potts requested the preparation of a report regarding the noted subject. He indicated the report should investigate the possibility of permitting left-turns, when safe, on red left-turn arrows when a green ball is indicated for the through traffic movement. Mayor Potts reinforced this request at the September 20, 1993 City Council meeting and also requested that the report address the possibility of implementing flashing red left-turn arrows at intersections. The Mayor also indicated that during the past year, the City of Irvine has been removing left-turn arrows at several locations throughout that City. DISCUSSION: In October 1991, the City's Engineering Division staff conducted a left-turn operation study which addressed a resident's concern with the use of red left-turn traffic signals and subsequent suggestion to install flashing yellow left-turn arrows in place of red arrows at the City's traffic-signal locations. The study indicated that left-turn arrows reduced traffic accidents, minimized delays during off-peak hours, reduced air pollution and fuel consumption. This study recommended, among other things, continuance of the City's current policy of installing protected l%ft-turn phasing on coordinated or arterial roadways. A copy of the study is attached for your information. This study was presented for City Council consideration at their meeting of January 6, 1992. After discussion of the item, the Council voted to receive and file the subject report. Copies of the aforementioned January 6, 1992 Agenda Item and the respective City Council minutes are attached for your information. To address Mayor Potts' recent concerns regarding left-turn operations, staff has consulted the Caltrans Traffic Manual, the Federal Manual of Uniform Traffic Control Devices, the California ~ehicle Code, and the attached October 1991 Traffic Signal Left Turn Operation Study. The Police Department has reviewed the left turn phasing concerns outlined in this report and concurs with staff's findings and conclusions. Based upon staff's investigation, it has been determined that neither permissible left-turn movements on red arrows or flashing red arrow indications at signalized intersections meet federal or state guidelines. It is indicated in the noted references, that vehicles must make a complete stop at red arrows and may not proceed' through a signalized intersection until the signal indications change to green, or as otherwise directed by an enforcement officer. Furthermore, the noted references indicate that flashing red arrows shall not be operated unless all signal faces on an approach are also flashing red. Actions to modify the City's traffic signal system to reflect the subject left-turn operations may place the City in a position of non-compliance within federal and state guidelines for such operations and subject the City to potential liability exposure. Also, it could cause significant driver confusion which may cause increased accident rates at City signalized interseCtion locations as well as at signalized locations within other jurisdictions. Procedures to change regulations regarding these issues would require consideration by the State of California Traffic Control Devices Committee and the Federal Highway Administration. Mayor Potts also indicated that the City of Irvine has removed left-turn arrows at several locations throughout that City. Based upon staff's review of this issue, it was learned that the City of Irvine has recently modified its left-turn policy for traffic signals. The City had be~n installing left-turn arrows on the minor intersection approaches in addition to the arterial street approaches at all signalized intersections. The Irvine City Council, at their meeting of September 24, 1991, directed their staff to remove left-turn arrows for minor street approaches at 44 traffic signal locations. The left-turn arrows for the major street approaches were to remain. In contrast, the City of Tustin has never installed left-turn arrows on minor street approaches unless the standard left'turn criteria has been met. Robert S. Ledendecker Director of Public Works/City Engineer Attachments ESL:DA: [eftturn ~Dou~las R. Anderson Transportation Engineer Page 6, 1-6-92 ' RESOLUTION ~O. 92-03 - A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF TUSTIN, CALIFORNIA, DESIGNATING PLACEMENT OF CERTAIN STOP SIGNS Motion carried 5-0. 3. REQUEST FOR STOP SIGNS ON "A" STREET AT SECOND STREET AND AT THIRD STREET 4. EMERGENCY PLACEMENT OF STOP SIGNB FOR THE INTERSECTIONS OF "A" STREET AT SECOND AND THIRD STREETS Robert Ledendecker, Director of Public Works,' reported that Item No. 3 was a warrant study regarding intersections at "A"/Second Streets and "A"/Third Streets. He stated that based upon State guidelines, the intersections did not warrant all-way stop control~. Mr. Ledendecker said that at the December 2 1991 Council meeting, Council ordered stop sign installation at "A#/Second Streets and "A#/Third Streets. Item No. 4 provided the administrative procedure to formally authorize the emergency placement of the four way stop sign installation at the subject intersections. It was ~oved by Potts, seconded by Pontiou~, to receive and file Item No. 3, Request For Stop Signs On "A" Street at Second Street and at Third Street. Councilmember Potts clarified the legality of Council's action to install the stop signs. .. Motion carried 5-0. It was moved by Edgar, seconded by pontious, to adopt the following Resolution No. 92-04 authorizing the emergency placement of a four-way stop sign installation at the intersection of "A" Street and Second Street and at the intersection of "A" Street and Third Street: RESOLUTION NO. 92-04 - A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF TUSTIN, CALIFORNIA, DESIGNATING PLACEMENT OF CERTAIN STOP SIGNS Motion carried 5-0. 5. REQUEST FOR REMOFAL OF LEFT TURN ARROWS AT TRAFFIC SIGNALS Dana Kasdan, Engineering Serwices Manager, reported that resident, Anthony Trujillo, had suggested that flashing yellow arrows be substituted for red left-turn traffic signal arrows. Staff had conducted a left-turn phasing policy study which indicated that left-turn arrows reduced traffic accidents, minimized delays during off-peak hours, reduced air pollution and fuel consumption. The study recommended installation of protected left-turn phasing on coordinated or arterial streets; continued conversion of four remaining protected/permissive left tuun intersections to protected heft-turn movements; and refrain from installing any new prctected/permissive signal phasing. He also stated that flashing ye!l~w left-turn arrows dio not meet Federal and State guidelines. Mr. Kasdan additionally reported that Councilmember Potts had requested an informatienal report reqarding the City of Irvine's removal of 44 left-turn arrows. He explained that the City cf Irvine Council had voted to remove left-turn arrows only for minor street approaches. Council/staff discussion followed regarding the timeline for upgrading the four protected/permissive left turn intersections; and the number of left-turn arrows on minor street approaches. The following member of the audience spoke on inaccuracies in the staff report: Anthony Trujillo, Tustin CITY COUNCIL MINUTES Page 7, 1-6-92 It was ~oved bY Potts, seconded by Prescott, to receive and file subject report. Councilmember Edgar stated traffic accidents had been reduced since implementation of the current left-turn phasing policy and traffic signal operations. Mayor Pro Tem Pontious commented that the new signal at Red Hill/Mitchell Avenues was very effective and eliminated considerable left-turn delay. Motion carried 5-0. 6. FEASIBILITY STUDY TO PROVIDE A MEDI~W OPENING ON TUSTIN RANCH ROAD AT PALERMO Councilmember Potts stated~the Almeria Homeowners' Association requested this item be continued for one month. It was moved by Potts, seconded by Edqa~, to continue this item to the February 3, 1992 meeting. Motion carried 5-0. XI. NEW BUSINESS 1. UNDERGROUND UTILITY DISTRICT NO. 11 - RED HILL AVENUE Robert Ledendecker, Director of Public Works, described the location of Underground Utility District No. 11 and reported that Southern California Edison Company had requested an extension for the removal of the overhead wires and utility poles from December 1, 1991 to June 1, 1992. It was moved by Edgar, seconded by Pontious, to approve the ' Edison Company request for time extension from December 1, 1991 to June 1, 1992 for the removal of the overhead wires and utility poles along Red.Hill Avenue and Copperfield Drive. Motion carried 5-0. 2. FORMATION OF ORANGE COUNTY FIRE PROTECTION DISTRICT Ronald Nault, Finance Director, repcrted staff worked with the Orange County Fire Department, the Structural Fire Fund cities, and the Cash Contract Cities evaluating the concept of regional fire services. In 1991 the contract cities formed a steering committee to investigate alternatives that would serve the Current demographic make-up of the Fire Department service area and the cities felt that creation of a Fire Protection District was the best alternative. The cities hired a consulting firm to evaluate 5he financial feasibility and other issues related to the fcrmation of a district and their findings were contained in Draft Final Report, Phase I. He stated funds had been appr'opr]ate/ in the budget; and staff believed it was in the City's ~est interest, and cost effective, to remain a participant in this formation. Council/staff discussion followed r~garding whether each city would have a voting representative in the district; current limitation of 11 members on the district panel; investigating contracting with the district or co?.'ersion to full membership of the district. It was moved by Potts, seconded by Pontious, to 1) Receive and file the Draft Final Report, ?~ase I, "An Evaluation of Financial Feasibility for an OranTe County Fire Protection District" and (2) Adopt the follc=ing Resolution-No. 92-01 agreeing to participate in the fornation of an Orange County Fire Protection District: RESOLUTION NO. 92-01 - A RESOL/3TION DF THE CITY COUNCIL OF THE CITY OF TUSTIN, CALIFORNIA, SU P?ORTING AND AGREEING TO PART ICI PATE IN THE FORMATION O.-- AN ORANGE COUNTY FI RE AGENDA DA,r:: DECEMBER 27, 1991 Inter-Com TO: WILLIAM A. HUSTON, CITY MANAGER FROM: PUBLIC WORKS DEPARTMENT/ENGINEERING DIVISION SUBJECT: REQUEST FOR TaE REMOVAL OF L..EFT TURN ARROWS AT TRAFFIC SIGNALS RECOMMENDATION Receive and file. BACKGROUND Mr. Anthony Trujillo appeared before the City Council at the meetings of March 4, and July 1, 1991, where he expressed concern about an abundance of red left-turn traffic signals and suggested that flashing yellow arrows could be used in place of red arrows. Staff has corresponded with him which has resulted in a study (attached) that provides information regarding the City's current left turn phasing policy, experience of the City's traffic signal operations, and recommendations. Councilmember Potts at the December 2, 1991, City Council meeting requested an information report regarding the City of Irvine's removal of 44 left turn arrows at traffic signals. The attached study noted above, also describes the City of Irvine's decision regarding the left turn arrows. DISCUSSION The study indicates that when left-turn arrows have been installed at traffic signals in the City of Tustin, traffic accidents have been substantially reduced. The delay to left-turning vehicles is considered minor during off-peak hours due to traffic responsive features of traffic signal controllers, and is felt to be a small price to pay for the additional safety.and other benefits such as: reduced air pollution, reduced overall delay, and reduced fuel consumption for the entire street system. The suggestion to utilize flashing yellow left-turn arrows has been investigated. Such an operation does-not meet current federal and state guidelines for traffic signal operation. The study recommends that the City should retain it's current policy of installing protected left turn phasing only on coordinated or arterial streets, should continue to convert the remaining four protected/permissive left turn intersections to protected left turn movements, and refrain from installing any new protected/permissive signal phasing. A copy of the study has been sent to Mr. Trujillo, and he has been advised that the matter has been agendized for City Council consideration at their meeting of January 6, 1992. The City of Irvine has recently modified its left-turn arrow policy fortraffic signals. The City had been installing left-turn arrows on the minor intersection approaches in addition to the arterial street approaches at all signalized intersections. The Irvine City Council, at their meeting of September 24, 1991, decided to remove left-turn arrows for the minor street approaches at 44 traffic signals. The left-turnarrows fort he major street approaches are to remain. In contrast, the City. of Tustin has never installed left-turn arrows on minor street a~proaches to major streets unless the standard left-turn criteria has been met.. Robert S. Ledend~ker Director of Public Works/ City Engineer ~Sandra Doubleday ~ Traffic Engineering Consultant RSL: kl, b: LE FTTURN Attachment ·., OCT 2 $1991 '~JSTIN PUBLIC WORKS TRAFFIC SIGNAL LEFT TURN OPERA TION STUD Y Presented by: BSI Consultants, Inc. Presented to: City of Tustin 15222 East Del Arno Tustin, CA 92680 October 1991 TABLE OF CONTENTS STATEMENT OF ISSUE ...................................... INTRODUCTION ............................................ TUSTIN'S CITY POLICY ON LEFT TURN PHASING .................... 1 TUSTIN'S PAST EXPERIENCE WITH PROTECTED/PERMISSIVE LEFT TURN SIGNAL OPERATIONS ................................... OTHER CITIES EXPERIENCES WITH PROTECTED/PERMISSIVE LEFT TURN SIGNAL OPERATIONS ................................... 3 PROTECTED/PERMISSIVE LEFT TURN SURVEY TABLE ............ 4 SUGGESTED GUIDELINES FOR EVALUATING PROTECTED/PERMISSIVE LEFT TURN SIGNAL LOCATIONS ........................... 5 IRVINE'S EXPERIENCE WITH LEFT TURN PHASING ................... 5 CONCLUSION AND RECOMMENDATIONS .......................... 6 AT'FACHMENTS ............................................. 6 SUBJECT Investigation into protected/permissive left turn phasing and the elimination of left turn arrows. RECOMMENDED ACTION Retain City's current Left Turn Policy of installing protected left turn phasing only on coordinated or arterial routes. Continue to convert the remaining four protected/permissive left turn intersections to protected left turn phasing. Refrain from installing any new protected/permissive signal phasing due to past experiences and the determination that this of phasing is not viable for use on coordinated routes. STATEM~NT OF THE ISSUF_~ OR PROBLEM Mr. Anthony Trujillo, a citizen of Tustin is concerned with the delay to left turning motorist due to exclusive left turn phasing. Mr. Trujillo has stated mat he feels this type of phasing unnecessarily increases the delay and wastes fuel. Mr. Trujillo requested that existing protected left turn red arrows be removed in the City of Tusfin to permit permissive left turns to occur. Mr. Trujillo feels this would decrease stop delays and save on fuel consumption. In a subsequent conversation with City staff, Mr. Trujillo suggested replacing the protected red arrow with a flashing yellow arrow as a method to warn motorist that permissive left turns would be permitted when sufficient gaps occurred in the approaching traffic. INTRODUCTION The purpose to this report is to gather information on the City of Tusfin's current city left turn phasing policy and past protected/permissive left turn phasing experience in order to explain the City's philosophy on traffic signal operations. This report also accumulated additional information from various cities and agencies in Orange County on protected/permissive traffic signal operations. In the protected/permissive type of operation, a car can either turn left on a fully protected interval indicated by a green arrow or, when there are adequate gaps in traffic, the car can turn during a green ball indication. This report also addresses the City of Irvine's recent decision to remove protected left turn arrows at numerous locations throughout their city. TUSTIN'S CITY POLICY ON LEFT TURN PHASING The City of Tustin has adopted a policy of installing protected left turn arrows at signalized intersections on all arterial route approaches where left turn phasing has previously been found to be warranted. The California's Department of Transportation established guidelines for left turn phases are used to determine when left turn phasing is warranted. For additional information see the attached section of the Traffic Manual entitled 9-03.0 Guidelines of Left Turn Phases. LEFTTURN.STY/DT TUS It has been Tustin experience that left turn accidents are substantially reduce~ when a left-turn arrow is provided. The left turning motorist does not have to make a judgement call when making a left turn when opposed by high traffic volumes and relatively high speeds. It is recognized that during coordination periods a red left turn arrow can delay left turning vehicles. This delay, however, is a small price to pay for the added safety, reduced air pollution, delay, and fuel consumption to the entire roadway system. During non-coo~a~ periods, the delaY to left turning vehicles is minor. This is due to the traffic signal controller being able to respond to lighter traffic conditions by serving the left mm only when there is demand. By removing the red arrow as suggested by Mr. Trujillo, the signal phasing would revert back to a protected/permissive phase. Mr. Trujillo's .suggestion of replacing existing red arrows at protecmd left turn traffic signal phasing with yellow flashing arrows would not meet current Uniform Traffic Control Standards. When a traffic signal is being operated as a flashing device, all Signal faces in an approach shall flash as stated in the Manual on Uniform Traffic Control Devices, 1988 Edition. This would not permit the left mm movement to flash yellow when the through traffic movement would show a solid green ball. Also the Manual on Uniform Traffic Control Devices states that no steady green indication or' flashing yellow indications shall be terminated and immediately followed by a steady red or flashing red indication without the display of the' steady yellow indication. Please find the appropriate sections of the Manual on Uniform Traffic Control Devices attached to the end of this report. TUSTIN'S PAST EXPERIENCE WITH PROTECTED/PERMISSIVE LEFT TURN SIGN.~L OPERATIONS The City installed their first project/permissive left turn phasing in 1977 at four intersections on McFadden Avenue. Ten intersections on Newport Avenue and Irvine Boulevard and one intersection at Red Hill Avenue and Carnegie Avenue were installed in 1981. In 1988, due to complaints from citizens and left mm accidents at these intersections, the City Council requested staff to review the City policy on the use of protected/permissive left mm phasing. One of the major problems with the protected/permissive left mm operations is the Trap, this condition occurs when one left turning vehicle (a) is stopped in the intersection on the green ball waiting for traffic to clear in order to make the left turn. If opposing left turn tr~,fffic is about to receive a protected left mm arrow (lagging left), then the left turn vehicle (a) will see a yellow ball and may assume that opposing through traffic also has a yellow. This assumption is wrong since the opposing traffic has a green ball and will soon receive a green left arrow. Thus, a trap is created if the left turning vehicle (a) attempts to turn on the yellow ball, and clear the intersection before the red. Due to this trap situation, a protected/permissive can not be leading in one direction and lagging in the other. They must both be either leading or lagging. LEFTTURN. STY.rDT TUS 2 The City ha~ an on-going program of coordinating all signals within the City. This coordination requires the use of lead/lag phasing in order to provide an adequate green band through a group of intersections. Approximately 30% of the signals in the City use lead/lag phasing now and, as more routes are coordinated, additional intersections will require use of lead/lag phasing. Another problem with the protected/permissive left turn operation is that once the left turn arrow has been received and is terminated by a yellow arrow (a left red arrow is not recommended), it is difficult to stop the flow of left turning vehicles. This creates additional enforcement problems for the police department as well as potential for increased accidents. Based on the staff review, it was recommended that no new protected/permissive left turns be installed and that existing ones be converted to protected. To date, all but four locations have been converted and they are scheduled for conversion in the near future. OTItER CITIES EXPERIENCF~ WITH PROTEC~D/PERMI~qSIVE LEFT TURN OPERATIONS For this study, a total of 15 cities, the County of Orange and Caltrans were contacted and surveyed on the subject of protected/permissive left turn operation. Of these 17 agencies, only a few had actually implemented policies on this type of operation. The following table summarizes the information gathered from this survey. Currently, most cities contacted had only a few intersections with protected/permissive phasing, if any at all. Some of the reasons given by the cities that do not implement protected/permissive operation are as follows: · Significant increase in accidents due to motorist misunderstanding of protective/permissive operation, or judgement error on the part of the motorist · Liability problems · Public opinion · Awaiting further studies to be done Of those cities that were using protected/permissive operation, most had experienced accidents attributed to protected/permissive phasing. Reasons given for these accidents were: · Driver misunderstanding of operation · Driver understood operation but made a judgement error All cities surveyed agreed that protected/permissive phasing does not make an intersection less prone to accidents, but with time it is hoped that driver understanding of this type of operation will bring the benefits that are intended without the accidents. mmv~.swmT ,us 3 The majority of those surveyed indicated that they would put protected/permissive operation in if the situation called for it, while there were a few who were trying to do away with it because of such reasons as public opinion. Also, there are those cities, as mentioned before, who are still awaiting the results of studies being done, and those who just have not looked into this type of operation much at all. PROTF~TED/PERMI~qSIVE LEFt TURN SURVEY TABLE Well-defined Number Plan to Install City/Agency Policy of Locations Accidents in Future Caltrans Yes. 5 in O.C. No. Yes. Irvine Yes. 0 N/A No. Anaheim Yes. 7 Yes. Yes. Huntington Beach Yes. Numerous Yes. Yes. Placentia Yes. 0 N/A Yes. , , Brea Yes. 1 No. Yes. Newport Beach Yes. 1 Yes. No. Costa Mesa Yes. Few Yes. Yes. Buena Park No. 0 N/A Yes. County of Orange No. i No. Yes. Cypress No. 0 N/A Yes. Fullerton No. 4 No. Yes. Garden Grove No. 0 N/A Yes. La Habra No. 2 No. Yes. La Palina No. 0 N/A Yes. Orange Yes. 0 N/A No. Santa Ana Yes. 0 N/A No. LEFIWURN.STY/DT TUS 4 SUGGESTED GUIDELINES FOR EVALUATING PROTECTED/PERMLqSIVE LEFr TURN SIGNAL LOCATIONS Listed below are suggested guidelines to follow when evaluating protected/permissive left turn operation locations. · Do not use permissive phase during ~ hours. · Avoid sequence lagging of protected/permissive/protected left turn. · Do not install at lagging left'iurn locations on coordinated routes. · Do not install if there were five or more accidents during a recent 12 month period. · Do not use if there is a sight distance problem, either vertical or horizontal. · Do not use with double left turn. · Do not use if opposing through traffic is greater than 40 mph. · Do no use where there is a large percentage of buses and/or trucks. · Do not use in high pedestrian areas. · Do not use if the street is near capacity. IRVINE'S REC£NT EXPERIENCE WITH LEFT TURN SIGNAL REMOVALS The City of Irvine. at its September 24, 1991 Council Meeting, directed staff to initiate removal of left turn phasing at 44 signals based on a report from staff. The City of Irvine's policy on left turn' phasing prior to the staff report was to install left turn arrows on all approaches, not just arterial approaches as in Tustin. The left turn arrows t~hat are being removed in Irvine are on the minor street approaches only. The City of Tustir. has never installed left turn phasing on these minor street approaches unless l~ft turn warrants were met. LEFTTURN.STY/DT TUS 5 CONCLUSION AND RECOMME~A~ONS On major intersections, protected left mrn arrows provide a safer operating intersection by reducing the number of potential conflicting movements. The City of Tusfin has an active signal coordination plan with 30% of intersections currently using lead/lag, lag/lead operation to maximize the efficiency of coordinated operation. For these reasons, it is recommended that the existing protected left mm operation be maintained. Also, from past experience with protected/permissive operation in the City of Tustin, it is recommended that this type of operation not be used at any coordinated arterial intersections. ATTACHMEaNTS: 2. 3. 4. Guidelines for Left Turn Phases - Traffic Manual City's Response Letter to Mr. Tmjillo City of Irvine's City Council Report on Removal of Left Turn Phasing Excerpts from the Manual on Uniform Traffic Control Devices LEFTrURN.STY/DT TUS 6 ATTACHMENT STATE OF CALIFORNIA DEPARTMENT OF TRANSPORTATION 1985-1 Issued by the DEPARTMENT OF TRANSPORTATION GEORGE DEUKMEJIAN Governor LEO TROMBATORE Director, Department of Transportation R. G. ADAMS Deputy Director, Highway Maintenance and Traflic Operations C. D. BARTELL Chief, Division of Traffic Engineering JOHN GOMES Editor 12-1986 TRAFFIC SIGNALS AND LIGHTING I Traffic Manual volume minor street approach (one direction only) for one hour (any four consecutive 15-minute peri- ods) of an average da),, falls above the curve in Fig- ure 9-2C for the existing combination of approach ]:meg. When the 85th percentile speed of major street traffic exceeds 40 miles per hour, or when the inter- section lies within a built-up area of a isolated com- munity having a population of less than 10,000, the peak hour volume warrant is satisfied when the plot- ted point, referred to above, falls above the curve in Figure 9-2D for the existing combination of approach lanes. ' :' 9-03.0 Guidelines for Left Turn Phases Since separate signal phases for protected left turns will reduce the green time available for other phases, alternate means of handling left turn con- flicts should be considered first. The most likely possibilities are: i. Prohibition of left turns. This can be done only if there are convenient alternate means of mak- ing the movement. Typical alternate means are: (a) a series of right and/or left turns around a block to permit getting to the desired destina- tion, or (b) making the left turn at an adjacent unsignalized intersection during gaps in the op- posing through traffic. 2. Geometric changes to eliminate the left turn. An effective change would be a complete sepa- ration or a complete or partial "clover leaF' at grade. Any of these, while eliminating left turns, requires additional cost and right of way. Protected left turn phases should be considered where such alternatives cannot be utilized, and one or more of the following conditions exist: 1. Accidents. Five or more left turn accidents for · a particular left turn movement during a recent 12-month period. 2. Delay. Left-turn delay of one or more vehicles ' which were waiting at the beginning of the green interval and are still remaining in the left turn lane after each cycle for one hour. 3. Volume. At new intersections where only. es- timated volumes are available, the following cri- teria may be used. For a pretimed signal or a background-cycle-controlled actuated signal, a left turn volume of more than two vehicles per approach per cycle for a peak hour; or for a traffic-actuated signal, 50 or more left turning · vehicles per hour in one direction with the product of the turning and conflicting through traffic during the peak hour of 100,000 or more. 4. Miscellaneous. Other factors that might be con- sidered are: consistency of signal phasing with that at adjacent intersections, impaired sight distance due to horizontal or vertical curvature, or where there is a large percentage of buses and trucks. 9-04.0 Removal of Existing Signals Changes in traffic patterns may result in a situation where a traffic signal is no longer justified. When this occurs, consideration should be given to removing the traffic signal and replacing it with appropriate alternative traffic control devices. City of Tustin ATTACHMENT ¢2 March .7, 1991 Mr. Anthony Trujillo 2001 Kingsboro Circle Ttistin,' CA' 92680 .... Subject: Protected Left Turn Phasing at Signalized Intersections Dear Mr. Trujillo: Thank you for attending the recent City of Tustin Council meeting on March 4, 1991. Thc matter of protected left turn phasing at signalized intersections is very important to public agencies. Public agencies, such as the City of Tustin, are responsible for installation, maintenance and optimization of the operation of these traffic signals. The types of protected movements most frequently used are: o at high rate accident locations, o where there are high number of turning movements, o where there are delays for on-coming traffic to clear, o along coordinated corridors. In addition, the City of Tustin has been involved with litigation pertaining to not providing protected left turn phasing at various signalized int_ersections. The CiD' Council has recently approved modifications to the existing traffic signals with permissive/protected left turn phasing to include the installation of protected left turn phasing. In addition, the Air Quality Management Plan of the AQMD specifically includes requirements that public agencies implement computer-coordinated traffic signal systems on major a:-terials in order to reduce air pollution, delay, and fuel consumption. Guidelines and minimum warrants have been established by State of California (Department of Transportation) for left turn phasing. A copy is attached for your information. 300 Centennial Way - Tustin, California 92680 - (714) 544-8890 Anthony Trujilio March 7, 1991 Page 2 It is our understanding that while driving at night (10 p.m. to 12 midnight), you have been stopped at some City intersections and have had to wait for a period of time for the green left-turn arrow, even though there was no on-coming traffic. A traffic signal controller normally has a certain sequence through which it must go in order to serve the direction a motorist is traveling. This takes time. However, in the late night hours, it should be fairly minimal, if there is no other conflicting traffic demand. If an unusually long delay is experienced, this may indicate that part of'the system (for example, traffic detector loops) may be malfunctioning and may need maintenance. If you 'are aware of any specific locations where such a malfunction may be occurring, please do not hesitate to report these to us. We sine-erely appreciate your concern, and if you have any questions please do not hesitate · to contact me. Sincerely, City of Tustin Ms. Sandra Doubleday Engineering Consultant SD:RR:dt Attachments CC: William A. Huston Robert S. Ledendecker ATTACHMENT REQUEST FOR CITY COUNCIL ACTION SEPTEMBER 24, 1991 COUNCIL MEETING DATE: DireCtor of Community Development -Ci%yg~an~ager RECOMMENDED ACTION: · Direct staff to initiate' removal of left turn phasing at intersections as outlined in the staff report based on available funding. · Direct staff to return in six months with a status report on the progress of the program. COMMISSION RECOMMENDATION: The Transportation Commission reviewed this issue at their August 26, 1991 meeting and unanimously supported implementation of the proposed program. EXECUTIVE SUMMARY: · Staff has been asked to consider safe criteria for ~dentifying potential intersection candidates Whereby signals could be converted from protected left-turns (exclusive phase with left- turn arrows) to permissive left-turns (combined phase where left turns occur by yielding to through traffic with circular green indication). The City currently maintains 197 signals, most of which have protected left-turns. When trying to coordinate traffic signals, delay becomes an important consideration. Staff has been asked to identify options which can help reduce delay at intersections. One such program is the elimination of protected left-turn phases where they are clearly not warranted. To achieve the goal' of reducing delay, and yet retain the high safety standards established Citywide, staff is recommending only 44 signals as potential candidates at this time. Advantages for this type of program include improved signal coordination, reduced delay, savings in fuel, and reduced air pollution among others. Improvement programs like this, which enhance signal timing and signal coordination, are consistent with the Circulation Element of the General Plan. Some disadvantages are driver expectation to see a green arrow, pedestrians contending with additional turning traffic, and potential safety implications· Because of the costs involved, it is recommended that only those locations where signal coordination is critical and where delay can be reduced safely be considered· Any other criteria, beyond that which has been discussed, should be reviewed in the upcoming City Traffic Management Systems and Operations Study. Public Safety has reviewed this issue and shares the safety concerns mentioned. RCJ:CL/pb(rfccaleftturnremoval.rpt) MEMORANDUM COUNCIL MEETING DATE: SEPTEMBER 24, 1991 TO: CITY MANAGER FROM: DIRECTOR OF COMMUNITY DEVELOPMENT SUBJECT: PROPOSED LEFT-TURN PHASING REMOVAL PROGRAM STATEMENT OF THE ISSUE.: The Transportation Commission has directed staff to implement a program for removal of protected left-turn phasing at various locations to reduce delay and improve signal coordination. TRANSYT-7F computer simulation studies indicate 10 - 15% reduction in intersection delay at certain locations. It is believed this may be accomplished without compromising safety by applying the criteria described in this report. Please note that the program will be implemented in four to six phases based on area locations in the City, traffic patterns, and circulation, so that more accurate costs and traffic factors can be studied and analyzed, as work proceeds. The tentative schedule would complete Westpark and Woodbridge in December, IBC in January, Spectrum in March, and Northwood in April. A public education program will accompany this project including newspaper articles, media information, and special signing, etc., to smooth the transition from one type of operation to another. Staff will also monitor the accident records and report any safety concerns. It should be noted that there are existing intersections Citywide without left-turnphasing presently which are not experiencing any special accident problems. ALTERNATIVES CONSIDERED: Staff reviewed two other alternatives: a) no change; b) removing all left-turn phasing. The concept of no change does not address the desire to reduce delay and improve mobility, which are contained as goals in the City's Circulation Element. Other options to reduce delay effectively are limited. The alternative to removing all left turn phasing was modified from 197 signal locations to approximately 44, based on other considerations, State guidelines, geometrics, safety, liability, and areawide consistency. cosT/souRc~ OF FUNDS: The cost associated with this program varies, depending on the equipment in place at each location. The initial cost estimate is $500 per direction resulting in approximately $50,000 for the entire program (44 intersections). Funding for the conversions will come from the existing signal maintenance account, and no new funding is being requested. Memorandum September 24, 1991 -2- RECOMMENDED ACTION: · Direct staff to initiate removal of left-turn phasing a't intersections as outlined in the staff report based on available funding. 2 .' Direct staff to return in six months with a status report on the progress of the program. Report prepared by: Conrad Lapinski, Principal Traffic Engineer Reviewed by: Arya Rohani, Manager of Transportation Services~ Submitted by: ~ · 'DIRE~-'~'OR OF COMMUNITY DEVELOPMENT RCJ: AR: CL/PB ( ccle ftturnremoval, rpt) Attachments: List of. potential locations for consideration Map of intersections cc: City Attorney LIST OF POTENTIAL LOCATIONS FOR CONSIDERATION Note: Ail intersections 1. Ada @ Alton 2. Arbor @ Walnut 3. Banting @ Alton 4. Bircher @ Alton 5. Burr @ Sand Canyon 6. California @ Campus 7. Construction So. @ Barranca · 8. Creek @ Alton 9. Dupont @ Michelson 10. Dupont @ Yon Karman 11. Eastwood @ Bryan 12. Fairbanks @ Alton 13. Fairbanks @ Irvine Blvd. 14. Fortune @ Gateway (1 direction) are for two directions unless ~tated 23. Murphy @ 24. Northwood @ Yale 25. Pacifica @ Barranca · 26. Parker @ Irvine Blvd. 27. Paseo Westpark @ Alton 28. Paseo Westpark @ Main 29. Paseo Westpark @ San Marino (All 4 directions) 30. Paseo Westpark @ San Remo (All 4 directions) 31. Roosevelt @ Yale 32. San Carlos @ Harvard 33. San Juan @ Harvard 34. San Leon @ Harvard 15. Fortune @ Pacifica (1 direction) 16. Gateway @ Irvine Center Drive 17. Hughes @ Alton 18. Kelvin @ Jamboree 19. Lake @ Alton 20. Martin @ Campus 21. Morgan @ Alton 35. San Marino @ Harvard 36. Sky Park N @ Red Hill 37. Sky Park S @ Main 38. Southwood @ Yale 39. Technology @ Barranca 40. Technology N @ Alton 41. Technology S @ Alton 42. Thomas @ Muirlands 22. Morse @ Von Karman 43. Westwood @ Bryan 44. Yale @ Irvine Center Drive ATTACHMENT, "[.. )" ' CITY OF IRVINE COMMUNITY DEVELOPMENT ONE DIRECTION TWO DIRECTIONS FOUR DIRECTIONS TRANSPORT~.TION SERVICES POTENTIAL LEFT TURN PHASING REMOVAL FIGURE