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Item 4CCITY OF SOUTHLAKE MEMORANDUM (February 21, 2012) To: Shana Yelverton, City Manager From: Robert H. Price, P.E., Public Works Director Subject: Approve a professional services agreement with Kimley- Horn and Associates, Inc. for design services for the FM 1709 Traffic Signal Timing Study project in the amount of $71,200 Action Requested: Approve a professional services agreement with Kimley- Horn and Associates, Inc. for design services for the FM 1709 Traffic Signal Timing Study project in the amount of $71,200 Background Information: TxDOT construction of the FM 1709 Median and Deceleration Lane project began in November 2010. Construction is still on- going. Raised medians have been installed from Pearson Lane to Nolen Drive. Irrigation, electric, and landscaping work will continue through completion. Deceleration lane construction is currently on- going. Anticipated completion of TxDOT's construction is summer 2012. With the addition of raised medians and deceleration lanes along FM 1709 from Pearson Lane to Commerce Street /Gateway Drive, u -turn and left turn volumes will be substantially greater at all intersections than they were when the corridor's traffic signals were re -timed in 2008. Kimley -Horn and Associates, Inc. (KHA) will develop new signal timing plans and assist with the implementation and fine - tuning of the traffic signals at all of the existing intersections along Southlake Boulevard. The intersections from west to east are as follows: Pearson Lane, Davis Boulevard /Randol Mill Road, Peytonville Avenue, Southridge Lakes Parkway /Waterford Drive, Shady Oaks Drive, White Chapel Boulevard, Byron Nelson Parkway /Diamond Boulevard, Carroll Avenue, Central Avenue, Village Center Drive, Kimball Avenue, Nolen Drive, Commerce Street /Gateway Drive. As part of the study, Kimley Horn will obtain the existing signal timing information from TxDOT, verify intersection roadway geometry, record traffic counts and turning movements, and evaluate vehicular and pedestrian clearance times. The consultant will also accompany TxDOT personnel as the new timing is implemented and will perform in the field fine - tuning of the signals. At the end of the project, the final timing plans and the electronic Synchro model will be provided to the city and TxDOT. The current schedule anticipates that construction of both the medians and the deceleration lanes will be completed by summer 2012. Financial Considerations: Funds for the study are included in the previously approved Capital Improvements Program project budget. The amount budgeted for the study was $90,000 from Red Light Camera funds. Strategic Link: The FM 1709 Median and Deceleration Lane project links to the city's strategy map relative to the focus areas of Mobility, Infrastructure and Performance Management and Service Delivery. The specific corporate objectives that are met by the construction of this project include Providing travel convenience within the City and the region, Providing high quality customer service, and Investing to provide and maintain high quality public assets. Citizen Input/ Board Review: None Legal Review: None Alternatives: The City Council may approve the Professional Services Agreement or deny it. Supporting Documents: Location Map Kimley -Horn Agreement Staff Recommendation: Approve a professional services agreement with Kimley- Horn and Associates, Inc. for design services for the FM 1709 Traffic Signal Timing Study project in the amount of $71,200 Staff Contact: Robert H. Price, P.E., Gordon J. Mayer, Jr., Cheryl Taylor, P.E., C Public Works Director P.E., City Engineer ivil Engineer a a Z O a v 0 J F- LU O a Project Understanding The Texas Department of Transportation (TxDOT) is currently implementing access management improvements on FM 1709 within Southlake. The project, which is scheduled to be completed in March 2012, includes the construction of a raised median. Because of the raised median, left turns will no longer be possible into or out of driveways and minor cross - streets. Instead, the traffic that formerly turned left into or out of these driveways will have to make u- turns at the median openings, almost all of which are at signalized intersections. Since the combined a -turn plus left -turn volumes will be substantially greater than they were when this corridor's traffic signals were re -timed in 2008, the City is undertaking this project to develop new signal timing plans. Because TxDOT will continue to operate and maintain the FM 1709 traffic signals, it is recommended that appropriate TxDOT personnel be involved in the review process as the new timing plans are developed. Also, it is assumed that the new timing will be implemented by TxDOT personnel with assistance and support from the Consultant. Scope of Services Project Intersections The project will include developing and assisting with the implementation and fine - tuning of updated traffic signal timing for the following thirteen (13) existing signalized intersections ( "Project intersections "): 1. FM 1709 & Pearson Lane 2. FM 1709 & Davis Boulevard (FM 1938) 3. FM 1709 & Peytonville Avenue 4. FM 1709 & Southridge Lakes Parkway /Waterford Drive 5. FM 1709 & Shady Oaks Drive 6. FM 1709 & White Chapel Boulevard 7. FM 1709 & Byron Nelson Parkway/Diamond Boulevard 8. FM 1709 & Carroll Avenue 9. FM 1709 & Central Avenue 10. FM 1709 & Village Center Drive 11. FM 1709 & Kimball Avenue 12. FM 1709 & Nolen Drive 13. FM 1709 & Commerce Street /Gateway Drive The City staff is aware of three (3) additional locations on FM 1709 where traffic signals may be needed in the future. One is at Jellico Circle/Watermere Drive, which is between the Pearson Lane and Davis Boulevard signals. Another is about is about 1,200 feet west of the Carroll Avenue signal. The third location is Meadowlark Lane /Players Circle, which is between the Peytonville Avenue and Davis Boulevard signals. To the extent practical, this project's new progression scheme should accommodate future signals at any or all of these locations. Kickoff Meeting At the outset of the project, the Consultant will prepare for and attend one kickoff meeting with the Client to begin the exchange of data to be provided to the Consultant. Also, various policy issues relative to signal timing will be discussed. Since TxDOT will continue to operate and maintain the traffic signals, it is assumed that TxDOT personnel will be invited to attend this meeting. Following the meeting, the Consultant will prepare and distribute a brief memorandum that summarizes the topics discussed and the consensus that was reached regarding signal timing policy issues. Assemble Existing Data The Consultant will obtain from TxDOT the current local controller and coordination timing for all project intersections. It is anticipated that this information will be provided in the form of printouts from the signal system database. This information will need to include the following: • Local controller timing parameters o Minimums and maximums • Vehicular clearances • Pedestrian timing • Phase sequences • Local special functions • Coordination timing • Cycle lengths, offsets, splits, and phase sequences • Time -of -day, day -of -week (TOD/DOW) schedules • Special events timing • System- commanded special functions As available and provided by the Client or TxDOT, the Consultant will also review any relevant traffic counts made subsequent to the 2008 re- timing project. Qualitative Assessment Using personnel experienced in traffic signal operations, the Consultant will perform an in -field qualitative traffic operations assessment. This will specifically include observing existing cycle lengths, splits, offsets, phase sequences, and left turn operations modes (e.g., permissive -only, protected - permissive, or protected - only). The Consultant will also identify by movement any intersection approaches where excessive queuing is observed, where capacity appears to be substantially constrained, and /or where excessive delay appears to be the result of inefficient signal operations. For all Project intersections, the Consultant will also make note of locations where possible changes in lane assignment may improve intersection operation. Another item that will specifically be observed is the interaction between u- turning traffic and traffic making right turns on red. All Project intersections will be observed during the weekday AM, midday, PM peaks as well as on Saturday afternoon. Verification of Arterial and Intersection Geometry and Pedestrian Accommodation The Consultant will perform a field inventory to collect or verify the following information: 2 Project intersections o Number of lanes and lane use • Modes of left turn operation • Existence of push buttons • Length of left -turn bays • Crosswalk and stop bar locations • Arterial segments between project intersections o Number of lanes o Posted speed limits Pedestrian accommodation (for each intersection side) • Walk/don't walk signals • Pushbuttons Traffic Counts The Consultant will make new recording machine traffic counts as following locations, which are the same as locations of counts made for the 2008 re- timing project. The data will be recorded by direction in 15- minute increments and totaled on an hourly basis. • One (1) 7 -day count will be made between Village Center Drive and Kimball Avenue • Two (2) 24 -hour weekday counts will be made. One will be west of White Chapel Boulevard and the other will be west of Jellico Circle New turning movement counts (TMCs) will be made at all Project intersections for the weekday AM, Midday, and PM peak periods plus one weekend peak period. The appropriate day (Saturday or Sunday) for the weekend peak will be determined from the 7 -day counts. For each peak period, data will be collected for six (6) consecutive 15- minute periods. For each 15- minute increment, the data will tabulated, by approach direction (e.g., northbound), and by turning movement (e.g., a -turn, left, straight, or right). The number of pedestrians crossing will also be tabulated by side of the intersection. Although the beginning and ending times will be adjusted based on the results of recording machine counts, the time periods will generally be as follows: • Weekday AM Peak (typically 6:30 AM to 8:30 AM) • Weekday Midday Peak (typically 11:30 AM to 1:30 PM) • Weekday PM Peak (typically 4:30 PM to 6:30 PM) • Weekend Midday Peak (typically 1:00 PM to 3:00 PM) Each of the weekday TMCs will be made on a non - holiday Tuesday, Wednesday, or Thursday when the Carroll ISD schools are in session. The weekend TMC will be made on a weekend when a holiday does not occur on Saturday or Sunday, the preceding Thursday or Friday, or the following Monday. Travel Time Runs "Before" and "after" travel time runs will be made during each of the four time periods for which a TMC was made. The one route will be FM 1709 from Pearson Lane to Commerce Street /Gateway Drive. During each time period, five runs will be made in each direction. These runs will be made using "floating car techniques ", i.e. the driver of the test vehicle car to travel at the pace set by other traffic. The "before" runs will be made prior to the implementation of any changes to the existing signal timing. These runs will establish baseline conditions (speeds, delay, and number of stops), to assist in the determination of appropriate progression speeds, and to identify areas where queue management is critical and areas where recurrent congestion may affect progressive traffic movement. Following the implementation and fine - tuning of the new signal timing, the "after" runs will be made to quantify the degree of improvement. Signal Warrant Anal This scope does not include the performance of signal warrant assessments. Clearance Interval Calculations The new 2011 edition of the Texas Manual on Uniform Traffic Control Devices (Texas MUTCD) became effective on December 8, 2011. That manual includes changes in the procedures for calculation of vehicular and pedestrian clearance times. As such, for all of the Project intersection, the Consultant will recalculate the clearance intervals in accordance with the new Texas MUTCD. For the vehicular yellows and all -reds, the following ITE formula* will be used: CP = t + V /(2a ± 64.4g) + (W + L)/V where: CP = non - dilemma change period (yellow plus all -red) t = perception- reaction time (nominally 1 second) V = approach speed (in ft /sec) g = percent grade (positive for upgrade, negative to downgrade) a = deceleration rate (ft/sec typically 10 ft /sec W = width of intersection, curb to curb (feet) L = length of vehicle (feet, typically 20 ft) * Source: Traffic Engineering Handbook, 6 th Edition, Institute of Transportation Engineers, Washington, DC 20005, 2009 The following criteria will be used to calculate the proper values for the pedestrian clearance interval: E • The assumed walking speed will be 3.5 feet per second unless a different standard value is mutually agreed upon at the outset of the project • The distance to be traversed will be from the near curb (or edge of pavement) to the middle of the far curb, and • It will be assumed that the end of the calculated pedestrian clearance will be timed concurrently with the associated vehicular clearance intervals (yellow and all -red). Number of New Timing Plans For the entire project area, five (5) new timing plans will be developed: • Weekday AM Peak • Weekday Midday Peak • Weekday PM Peak • Weekend Peak • Off -peak The off -peak timing plan will be intended for use during time periods when traffic volumes are relatively low but still great enough for coordinated operation to be desirable. Typical times when this timing plan may be desirable will include weekday mornings between 9 and 11 AM, evenings between 7 and 10 PM, and certain hours on weekend mornings. Update SynchroTM Models The Consultant will update the SynchroTM files of the final (i.e., as- fine - tuned) signal timing from the 2008 re- timing project. These models will be updated to reflect geometric changes as well as subsequent timing changes reflected in the data provided by TxDOT. The new TMCs made for this project will be used to update the traffic volume information. The newly calculated clearance times will also be incorporated into the models. The Consultant will then use the following process to calibrate the PM Peak model for existing peak conditions. The model's link speeds will be adjusted to achieve a reasonable correlation with actual corridor travel times as determined during the qualitative assessments and the before travel time runs. The SimTraffic feature will be used to perform a qualitative (i.e., visual) assessment of the adequacy of the calibration. Specific factors that will be reviewed include queue lengths and the locations of significant stops and delays. Iterative adjustments will be made until reasonable calibration is achieved. Once the "existing" PM peak model has been satisfactorily calibrated, the same procedures will be used to update and calibrate the "existing" models for the AM, Midday, and Weekend Peak time periods. The Synchro model for the off -peak timing plan will be developed using approximately 70 percent of the counted volumes the weekday midday peak. The exact percentage will be based on factors derived from the 7 -day counts. Intersection Operations Assessment During the qualitative assessment and field verification, the Consultant will identify possible opportunities to improvement intersection operations through lane assignment changes (e.g., by 5 changing a straight -only lane to a shared left- through lane). Using the SynchroTM models and new TMC data, the Consultant will quantitatively assess the benefits of such possible changes. The Consultant will prepare and submit a brief technical memorandum that discusses the following: • Recommended lane assignment changes • Recommended changes in crosswalk or stop bar locations Cycle Length Requirements and Control Area Boundaries Using the SynchroTM models, the practical minimum cycle lengths of the major intersections will be determined for all four timing plan periods. For the timing plans developed in 2008, all of the FM 1709 signals in both Southlake and Keller were part of the same control area. In other words, all of these signals operated at a common cycle length during each peak period. Having just one control area is desirable since progression cannot be provided across the boundary between control groups that are operating at different cycle lengths. For each of this project's updated timing plans, the intent will be to find one common cycle at which it is possible for all of the Project intersections to operate. More than one control group will be assumed to be necessary only if there are substantial differences among the shortest practical cycle lengths and /or it is not feasible to obtain reasonably good two -way progression for all intersections at a common cycle length. Also, wherever feasible and appropriate, the intent will be for this project's new timing plans to interface as smoothly as possible with the existing coordinate timing at adjacent intersections. Considering all of these factors, the Consultant will determine the most appropriate control groups. Develop Preliminary Timing Plans Each of the five (5) new timing plans will be developed using the following process. • Synchro's optimization process will be used to generate a "first cut" version of the timing plan. • "On- screen" review and adjustment will then be performed by senior engineers with extensive experience in traffic signal operations: o At intersections that are not over - saturated, SynchroTM tends to allocate more time than necessary to minor movements. Accordingly, the splits for non - coordinated phases will be reduced to provide additional split times for the coordinated phases. o The progression bands will be reviewed and offset will be made to improve operations for the coordinated movements. Also, to the extent possible without creating a yellow trap, phase sequence adjustments will be made. D For capacity- critical intersections, the Consultant will review the TMC data to determine if multiple splits appear to be needed. For example, if the peak 15- minute volumes occur at the same time for all movements, only one split will be presumed to be needed. However, if the peak 15- minute period for one critical movement occurs substantially earlier or later than the peak 15- minute period for other critical movements, it may be appropriate for that timing plan to have more than one split at that intersection. Develop Preliminary Time -of -Day Schedule Using the seven -day count data, the Consultant will develop a recommended time -of -day /day -of- week (TOD /DOW) schedule for operation of the new signal timing plans. Timing Plan Review Meeting The Consultant will prepare for and attend up to two (2) meetings in Southlake to review the proposed timing plans. The Consultant will present the proposed timing plans and TOD /DOW schedules to the Client and TxDOT. The Consultant will also present recommendations for any operational changes that appear to be needed due to interactions between a -turns and right turns on red. An LCD projector will be used so that the effects of possible timing plan modifications can be viewed on- screen. Through interactive discussions, consensus will be reached regarding modifications to be made before the new timing plans are implemented. Following these meetings, the Consultant will make the agreed -upon modifications and prepare the timing plan data in the format needed by TxDOT personnel to enter the new timing into the controllers. This will consist of SynchroTM timing sheet print -outs of the intersection timing along with a table showing the new time -of -day schedule. Given the number of intersections and timing plans, it is assumed that not more than two (2) review meetings will be required to reach consensus regarding the new timing plans. Timing Plan Data Entry The actual entry of new timing plans into the controller databases will be done by the TxDOT's staff. This is typically done by first entering the timing data into a laptop computer. During this process, the Consultant will provide on -call support to resolve issues that may arise. Timing Plan Implementation and Fine - Tuning The Consultant will accompany TxDOT as the new timing is downloaded from the laptop computer into the controllers. The Consultant will then perform in -field fine - tuning to enhance the actual on- street operation of the new timing plans. This fine - tuning will be led by senior engineers with extensive experience in traffic signal operations. It is assumed that TxDOT personnel will be on -hand to download desired timing adjustments into the controller databases. 7 The fine - tuning for the five (5) new timing plans will be performed as soon as practical. If such fine - tuning is initially performed during the summer of 2012, follow -up fine - tuning will be performed in early September 2012 after the 2012 -13 Carroll ISD school year has begun. Final Documentation Using the same process previously described for the "before" runs, the Consultant will make the "after" travel time runs. The locations, times -of -day, and number of runs will be the same as for the "before" runs. The Consultant will develop a project final report the will include the following; Executive summary Narrative discussion of the Project with supporting figures such as maps of the control groups by time period Tabular comparisons of the before and after travel time runs The Consultant will submit a draft version of the final report for review by the Client and TxDOT. Seven (7) copies will be provided — five (5) for the Client and two (2) copies for TxDOT. Following receipt of comments, the Consultant will prepare and submit a sealed final report. Twelve (12) copies will be provided — ten (10) for the Client and two (2) copies for TxDOT. The Consultant will also provide the Client with a PDF version of the sealed final report. The Consultant will provide the Client and TxDOT with documentation of the final (i.e., as fine - tuned) timing plans. This will be in form of SynchroTM timing sheet print -outs of the final intersection timing along with a table showing the final time -of -day schedule. For both the Client and TxDOT, the Consultant will also provide copies of the final SynchroTM electronic files.