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PZ Item 10 - Queueing Memo TNP Firm Registrations Texas Board of Professional Engineers, Firm No. F-230 | Georgia Board of Professional Engineers, Firm No. PEF007431 Texas Board of Professional Land Surveying, Firm No. 10011600 | 10194381 | 10011601 Texas Board of Architectural Examiners, Firm No. BR 2673 engineers surveyors landscape architects www.tnpinc.com TEXAS FORT WORTH DENTON ALLEN SAN ANTONIO CYPRESS SUGAR LAND GEORGIA BLAIRSVILLE ALBANY TEXAS FORT WORTH DENTON ALLEN SAN ANTONIO CYPRESS SUGAR LAND GEORGIA BLAIRSVILLE ALBANY Memorandum To: City of Southlake, Stephanie Taylor, P.E. – Transportation Manger From: Chris Edwards, P.E. CC: Philip Varughese, P.E. Date: April 8, 2020 RE: Keller ISD Queueing Analysis: Florence Elementary School Replacement Teague Nall & Perkins, Inc. has performed a queuing analysis to evaluate the on-site storage demands for the proposed Florence Elementary School Replacement in Keller Independent School District (KISD). Florence Elementary is located at the intersection of Johnson Road and Harrell Drive in Southlake, Texas. The site location and site plan are shown in Figure 1 and Figure 2, respectively. Figure 1: Florence Elementary School Site Location 2 Florence Elementary School Replacement is planned to open in August 2021, with an initial population of 472 students served by approximately 40 faculty and staff. In August 2031 (10 years after opening), the school is expected to reach an ultimate capacity of 572 students. The parking areas are divided into two separate areas to accommodate faculty and staff parking, parent drop-off/pick-up, and bus loading zones. The available parent pickup drive is approximately 1,065 linear feet (LF) from entrance to the furthest pick-up location. The bus drive is expected to be approximately 725 LF. In addition, the site provides 169 on-site parking spaces, of which 8 are accessible parking spaces. Figure 2: Proposed Florence Elementary School Replacement Site Plan 3 I. DATA COLLECTION Trip generation data is based on information provided in the Trip Generation Manual, 10th Edition, 2017 and the Trip Generation Handbook, 3rd Edition, 2014, developed by the Institute of Transportation Engineers (ITE). The average Weekday, PM Peak Hour of Generator trip rate for Elementary Schools (ITE Land Use 520) is 0.34 trip generations per student (see Appendix A). The traffic characteristics assumed for this analysis are as follows: • The afternoon pickup will have a longer queue than the morning drop-off. Morning drop-off activity is more temporally distributed and queue occupancy times are significantly lower. For afternoon pickup, many vehicles arrive prior to release time and must wait in queue until students are dismissed. Therefore, the afternoon pickup is considered more important for calculating on-site storage queue lengths; • The PM Peak Hour of Generator coincides with the KISD dismissal time for elementary schools, currently 3:10 PM. • From previous data collection, 67% of vehicular trips will queue before student dismissal, and 33% will arrive after dismissal; • The students will board the buses in the bus loading zone, precluding buses from using queue storage in the student pick-up lanes; The number of PM peak trips generated by the proposed Florence Elementary School Replacement in the opening year of 2021, and the ultimate design year of 2031, are computed in Table 1. Table 1: Expected Florence Elementary School Replacement Personal Vehicle Volumes II. QUEUE LENGTH ANALYSIS To accommodate queue length, the proposed elementary site has the following characteristics. The proposed parent loop for student pick-up/drop-off is designed to be 24’ wide to accommodate two lanes of queuing, resulting in 2,130 LF of storage. A total of 169 parking spaces are provided on site and the school employs approximately 40 faculty and staff members. Assuming each faculty and staff member drives separately to work, 121 spaces remain available for parent parking (does not include accessible parking), which may further reduce the expected queue by 2,420 LF (assuming 20’ per car). To estimate queue lengths generated prior to school release, the following assumptions were made: • Each vehicle occupies 20 feet of queue length; • 67% of the projected vehicles are expected to arrive at the school prior to student release; • There are 169 parking spaces planned on the campus, of which 8 are accessible spaces. A total of 121 spaces are available after allowing for faculty/staff and leaving accessible spaces open. Year:2021 2031 Total Number of Students: 472 572 Total PM Peak Trips Generated (0.34 trips/student):160 194 Percentage of Trips Queueing before dismissal: 0.67 0.67 Personal Vehicles expected in Peak Queue: 108 130 4 Using these assumptions, the estimated storage length needed to accommodate the expected total queue length before the school release time is approximately 2,160 LF, based on 108 vehicles in 2021. The storage length needed in 2031 is approximately 2,600 LF, based on 130 vehicles. The following table contains the calculated and provided length of queuing space as designed on the site plan for the initial student population in 2021 and with full build-out conditions and enrollment in 2031. Table 2: Calculated and Provided Queue Storage Figure 3 shows the proposed Florence Elementary School Replacement and some of the surrounding roadway network. The figure shows that the calculated pick-up queue (2,160 LF in Year 2021 and 2,600 LF in Year 2031) can be accommodated within the proposed elementary school site if a portion of the available parking is utilized. 2021 472 108 2,160 2,130 2,420 4,550 2031 572 130 2,600 2,130 2,420 4,550 Year No. of Students No. of Personal Vehicles expected in Queue Linear Feet of Queue Storage Storage Needed Queue Lane Storage Parking Storage Total Storage 5 Figure 3: Proposed Florence Elementary School Replacement Pickup Queue III. CONCLUSIONS AND RECOMMENDATIONS The queueing study for the proposed Florence Elementary School Replacement in KISD is provided to determine the expected storage requirements for afternoon pickup based on the peak vehicle queue typically occurring during dismissal. This study is based on expected characteristics of the proposed school, characteristics of nearby schools, and information provided in the Trip Generation Manual, 10th Edition, 2017 and the Trip Generation Handbook, 3rd Edition, 2014, developed by the Institute of Transportation Engineers (ITE). The queuing analysis shows that all queued vehicles will be maintained within the school property 6 during the peak periods and not impede the flow of traffic on adjacent streets. The parent loops are designed to minimize or eliminate any crossing of traffic flows within the queuing area. In addition to the parent loops, there are 121 open parking spaces available to accommodate an additional 2,420 LF of queue. Based on best planning practices, the following strategies to minimize peak queuing conditions on school campuses can be considered: • Create safe routes for pedestrians and bicyclists to encourage use of these modes instead of trips by vehicle. School administration can also actively promote walking or biking to school among students. • Utilize the 121 standard parking spaces expected to be available for parents that arrive early. To ensure parents use these spaces instead of the joining the queue, it is suggested that they receive direction to use these parking spaces. • Enforce “No Parking” along the circulation path during drop-off and pick-up operations. • Student pick-up area is inside the school campus and not along the street. • No unattended vehicles should be in the queue line. Parking spaces are provided if parents need to leave their vehicles. • Staff and/or volunteers should assist in loading students. • It is recommended that a school representative stand near the entrance to the parent pick- up driveway and, if the drives are full, direct traffic to use the available parking spaces for queueing purposes. 7 Appendix A ITE Trip Generation for Elementary Schools (Land Use 520) PM Peak Hour of Generator