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12131 113th Avenue NE, Suite 203, Kirkland, WA 98034 I [PHONE REDACTED] I TECHNICAL MEMORANDUM Date: August 16, 2018 TG: 17001.00 To: Min Luo, P.E., PTOE – City of Redmond From: Ryan Peterson, P.E., PTOE – Transpo Group Subject: Rose Hill West, Trip Generation Study This memorandum describes UCP Rose Hill’s proposed Rose Hill West project. The scope of this analysis has been previously approved by City of Redmond staff and includes a review of traffic safety, trip generation estimates, pipeline and with-project traffic volumes, traffic operations at both NE 100th Street/132nd Avenue NE and site accesses, signal warrant analysis, and mitigation measures. Project Description The proposed project includes the construction of 35 single-family residential units located west of 138th Avenue NE and south of NE 100th Street. Two access points are proposed south of NE 100th Street. The project site is currently occupied by four single-family residential dwelling units. Figure 1 shows the project site and surrounding vicinity and Figure 2 shows the preliminary site plan. It is anticipated the development would be completed and occupied by 2019. Figure 1. Site Vicinity ---PAGE BREAK--- 2 Traffic Safety Recent collision records were reviewed within the study area to identify existing traffic safety issues at the study intersection. The most recent five-year summary of accident data available from the WSDOT is for the period between January 1, 2013 and December 31, 2017. In addition to the intersection, collision data along roadways surrounding the study intersection was also reviewed. This information is summarized in Table 1. Figure 2. Preliminary Site Plan ---PAGE BREAK--- 3 Table 1. Five-Year Collision Summary – 2013-2017 Location Traffic Control Number of Collisions Total Annual Average ADT1 Collision s per MEV2 2013 2014 2015 2016 2017 Intersection 1. 132nd Avenue NE/NE 100th Street Unsignalized 2 2 1 3 4 12 2.40 15,550 0.42 Roadway Segments 132nd Avenue NE Corridor NE 95th Street to NE 104th Street - 1 1 1 3 3 9 1.80 - - NE 100th Street Corridor 128th Avenue NE to 138th Avenue NE - 0 0 0 1 2 3 0.60 - - 1. ADT = Annual Daily Traffic. ADT estimated by applying a factor of 10 to the PM peak hour total entering vehicles at the intersection. 2. Million Entering Vehicles A review of collisions was conducted for the study intersection and specified roadway segments. The study intersection and corresponding roadway segments each demonstrated annual averages of 3 collisions per year or less. The collision rate is representative of the number of collisions per one million entering vehicles (MEV) at the study intersection. Intersections with a rate greater than 1.0 collision per MEV are typically identified for further investigation to determine whether an adverse condition exists. As shown in the table, the study intersection of 132nd Avenue NE/NE 100th Street has approximately 0.42 collisions per MEV and does not indicate any specific adverse safety condition. Trip Generation The following table illustrates the anticipated number of net new daily, AM peak hour, and PM peak hour vehicle trips the proposed development would likely generate. These estimates were derived by applying the proposed and existing number of units to the daily and peak hour trip generation fitted curve equations for Land Use Code No. 210 (“Single-Family Detached Housing”) published by the Institute of Transportation Engineers (ITE) in the Trip Generation Manual (10th Edition, 2017). Net new trips were calculated by subtracting trips generated by the existing residential units from trips generated by the proposed units. Table 2. Estimated Weekday Vehicle Trip Generation1 Land Use Size Daily Trips AM Peak-Hour Trips PM Peak-Hour Trips In Out Total In Out Total Proposed Use Single-Family Detached Housing (LU #210) 35 DU 396 8 22 30 23 14 37 Existing Use Single-Family Detached Housing (LU #210) 4 DU 54 2 6 8 3 2 5 Net New Vehicle Trips 342 6 16 22 20 12 32 Notes: DU= dwelling unit 1. Trip generation based on ITE Trip Generation (10th Edition, 2017). ---PAGE BREAK--- 4 As illustrated above, the proposed development is anticipated to generate approximately 342 net new daily vehicle trips, with 22 new trips generated during the AM peak hour and 32 new trips generated during the PM peak hour. Traffic Volumes AM and PM peak period traffic counts were collected at NE 100th Street/132nd Avenue NE in October 2017. In addition, 12-hour vehicle volumes were collected in August 2018 on each approach of the NE 100th Street/132nd Avenue NE intersection. Detailed intersection traffic counts are provided in Attachment A. Future horizon year (2019) without-project AM and PM peak hour traffic volumes were estimated at NE 100th Street/132nd Avenue NE by increasing existing through traffic by an annual growth rate of 2 percent and adding project trips from other developments in the project vicinity (“pipeline projects”). Anticipated traffic volumes from the following 8 developments were identified via City of Redmond’s Project Viewer and were used to develop the future without-project traffic volumes: North Rose Hill Short Plat (6 lots) Willow Hill – Lot 9 (9 lots) Fu Short Plat (2 lots) Short Tom-Duplex (2 units) Benjamin Estates (14 lots) Gabarino Property (15 lots) Heather’s Ridge (8 lots) Rose Hill Preliminary Plat (29 lots) A total of 8 developments (either permitted or under construction) were identified in the site vicinity with sizes ranging from 2 units to 29 single family homes. It should be noted that for the developments east of 132nd Avenue NE and north of NE 100th Street, it was assumed that half of the estimated trips travelling to/from the north would use NE 100th Street to access 132nd Avenue NE and half would use NE 104th Street to the north. As a conservative assumption, it was assumed approximately 9 single family homes located south of NE 100th Street could use 138th Avenue NE to access NE 100th Street and would act as through movements at the proposed project’s site access locations. Pipeline traffic and project-generated traffic were assigned to the roadway network based on separate AM and PM distributions. These distributions were based on existing counts at NE 100th Street/132nd Avenue NE, and are consistent with analysis completed for the Rose Hill Preliminary Plat adjacent to the project site. Previously conducted AM and PM peak period traffic counts from March 2016 (projected to 2019) at NE 100th Street/132nd Avenue NE are used in developing trip distributions for the development. During the AM peak hour, 60 percent of traffic is distributed to and from the south via 132nd Avenue NE, 35 percent to and from the north via 132nd Avenue NE, and 5 percent to and from the west via NE 100th Street. The AM peak hour distribution is shown on Figure 3. ---PAGE BREAK--- 5 During the PM peak hour, 90 percent of the project trips are expected to access the site from the south while the remaining 10 percent would access from the north. The PM Peak hour distribution is shown on Figure 4. Figure 4. PM Peak Hour Distribution and Assignment Figure 3. AM Peak Hour Distribution and Assignment ---PAGE BREAK--- 6 Two site accesses on NE 100th Street, at 137th Place NE and 138th Avenue NE, were evaluated under future with-project conditions. It is anticipated that approximately 50 percent of the project generated trips would access the site from each of the two site accesses, respectively. Existing (2017) AM and PM peak hour volumes were rounded to the nearest 5 vehicles to account for daily traffic fluctuations from October 2017 counts. Future (2019) volumes were estimated using a 2 percent per year growth rate between the existing (2017) analysis year and the future (2019) analysis year. Existing (2017), future (2019) without-project, and future (2019) with-project traffic volumes are summarized in Figure 5. Traffic Operations Intersection level of service (LOS) for existing, future without-, and with-project conditions were evaluated at the 132nd Avenue NE/NE 100th Street intersection along with the site accesses using the 9 software program based on procedures identified in the Highway Capacity Manual (HCM, 2010). All intersection parameters such as channelization and intersection control were consistent through all analysis scenarios. At side-street stop-controlled intersections, LOS is measured in average delay per vehicle during the peak hour of traffic and is reported for the worst operating movement of the intersection. Attachment B provides a detailed explanation of LOS criteria and definitions. Detailed LOS worksheets are provided in Attachment C. Figure 5. Existing (2017), Future (2019) Without-Project, and Future (2019) With-Project Peak Hour Traffic Volumes ---PAGE BREAK--- 7 Table 3. Estimated Weekday AM and PM Peak Hour Traffic Operations Intersection Existing (2017) 2019 Without-Project 2019 With-Project LOS1 Delay2 WM3 LOS Delay WM LOS Delay WM AM Peak Hour 1. 132nd Avenue NE/NE 100th Street D 27 WB E 43 WB F 51 WB A. 137th Place NE/Site Access A - - - - - - A 9 NB B. 138th Avenue NE/Site Access B - - - - - - A 9 NB PM Peak Hour 1. 132nd Avenue NE/NE 100th Street F >180 WB F >180 WB F >180 WB A. 137th Place NE/Site Access A - - - - - - A 9 NB B. 138th Avenue NE/Site Access B - - - - - - A 9 NB Note: WB = westbound approach, NB = northbound approach 1. Level of Service (A – F) as defined by the 2010 Highway Capacity Manual (HCM), Transportation Research Board. 2. Average delay per vehicle in seconds. 3. Worst movement reported for unsignalized intersections. The City of Redmond operations standard is LOS D or better. As shown in Table 2, during the AM peak hour, 132nd Avenue NE/NE 100th Street operates at LOS D under existing conditions and LOS E under future without-project conditions. With the addition of project traffic, the 132nd Avenue NE/NE 100th Street intersection is anticipated to degrade from LOS E to LOS F with an increase in delay of approximately 8 seconds, and an increase in vehicle queue length of approximately 1 vehicle at the worst movement (westbound approach). During the PM peak hour, the 132nd Avenue NE/NE 100th Street intersection is anticipated to operate at LOS F under all three analysis conditions. Under future with-project conditions, westbound queues are anticipated to experience an increase of about 2 vehicles compared to without-project conditions. Under both AM and PM peak hour periods, the site access intersections are anticipated to operate at LOS A with less than 10 seconds of delay. Maximum queues at the site accesses are anticipated to be no more than 1 vehicle. Signal Warrant Analysis A signal warrant1 analysis was conducted for the 132nd Avenue NE/NE 100th Street intersection under with-project conditions. The following presents the data (geometry and traffic volumes) used to perform the signal warrant analysis of Warrants 1 through 3 and 7, as well as the findings. Intersection Geometry and Traffic Volumes The existing 132nd Avenue NE/NE 100th Street intersection is a 4-way intersection and is stop- controlled for the eastbound and westbound approaches. The future (2019) with-project weekday AM and PM peak hour traffic volumes at the intersection, as previously mentioned, are shown in Figure 5. For Warrants 1 and 2, 12-hour vehicle counts were collected in August 2018 to provide a localized hourly distribution of traffic volumes by approach over the course of the 7 a.m. to 7 p.m. warrant time frame. Daily pipeline and project trips were then scaled using this localized hourly distribution and added to the 12-hour traffic counts (the northbound and southbound through movements of the 12-hour counts were grown at 2 percent for 3 years, mirroring the growth process previously described). This layering of daily pipeline and project trips added to post-growth rate 12-hour 1 Manual on Uniform Traffic Control Devices (MUTCD), Federal Highways Administration (2009). ---PAGE BREAK--- 8 counts provides a conservative representation of future traffic volumes at the intersection because daily trip generation was assumed to occur within a 12-hour period. Analysis for Warrant 3 did not include the use of the 12-hour traffic counts; rather the volumes used for warrant 3 were the same future (2019) with-project volumes used in the traffic operations analysis. Both AM and PM peak hours were analyzed. Average peak hour vehicle delays from the traffic operations analysis were input as well. The following sections provide a summary of the methodology for the signal warrants evaluated for the 132nd Avenue NE/NE 100th Street intersection (Warrants 1, 2, and Warrant 1 – Eight Hour Vehicular Volume Warrant 1 consists of two conditions that independently assess whether a traffic signal is warranted based on traffic volumes. The first condition (Condition A) determines if traffic volumes at an intersection are consistently high enough throughout an average weekday to warrant the installation of a signal. The second condition (Condition B) is considered when Condition A is not met, and assesses whether traffic on the minor street experiences excessive delay due to high traffic volumes on the major street throughout an average weekday. These two conditions are combined such that fulfilling either of the two conditions would meet the warrant for installation of a signal. Detailed volume threshold criteria are identified for these conditions in the warrant methodology, and if traffic volumes exceed these thresholds for 8 or more hours on an average weekday, the signal warrant is satisfied. Alternatively, if neither of Conditions A or B are met, the volume criteria for both conditions can be reduced to 80 percent of their values such that if both conditions are then met, then installation of a traffic signal could be warranted. Based on the future with-project traffic volumes shown in Attachment D, Warrant 1 would not be satisfied as documented in the traffic volume signal warrant worksheet also provided in Attachment D. Warrant 2 – Four Hour Vehicular Volume Signal Warrant 2 is applied where the volume of intersecting traffic is the primary reason for considering installation of a traffic signal. The warrant is satisfied by comparing the traffic volumes on the major street and minor street with a chart included in the MUTCD. If the major and minor street traffic volumes intersect above the MUTCD chart threshold for four or more one-hour periods, then the signal warrant would be satisfied. Based on the future with-project traffic volumes shown in Attachment D, Warrant 2 would not be satisfied as documented in the traffic volume signal warrant worksheet provided in Attachment D. Warrant 3 – Peak Hour Signal Warrant 3 is applied when, for a minimum of one-hour of an average day, the minor-street traffic suffers undue delay when entering or crossing the major street. The warrant is satisfied by one of two categories are met: If all three of the following conditions exist for four consecutive 15-minute periods: o The total stopped time delay by traffic on one of the minor street approaches controlled by a stop sign exceeds 4 vehicle hours for a one lane road; and o The volume on the same minor street approach (one direction only) exceeds 100 vehicles per hour for one moving lane; and o The total entering volume serviced for during the hour equals or exceeds 800 vehicles per hour for four or more approaches. ---PAGE BREAK--- 9 Comparing the traffic volumes on the major street and minor street with a chart included in the MUTCD. If the major street traffic volume and the highest minor street approach volume intersect above the MUTCD chart threshold for four or more one-hour periods, then the signal warrant would be satisfied. It should be considered that MUTCD notes that this particular signal warrant “shall only be applied in unusual cases such as office complexes, manufacturing plants, industrial complexes, or high- occupancy vehicle facilities that attract or discharge large numbers of vehicles over a short time” (MUTCD, 2009). It is unclear as to whether the intersection of 132nd Avenue NE/NE 100th Street meets this criterion. Regardless, based on the future with-project traffic volumes shown in Attachment D, Warrant 3 would not be satisfied as documented in the traffic volume signal warrant worksheet provided in Attachment D. Warrant 7 – Crash Experience Signal warrant 7 is applied when collision experience at an intersection may be a potential cause for installation of a signal. The warrant considers collisions that may be corrected with the addition of a traffic signal and is met when five or more collisions are reported within a 12-month period. In 2017, four collisions occurred at the 132nd Avenue NE/NE 100th Street intersection. This was taken into account under the signal warrant analysis inputs. Warrant 7 would not be satisfied as documented in the signal warrant worksheet provided in Attachment D. When considering additional trips generated from potential future residential units in the area, signal warrant 7C (80% Volumes for Warrants 1A, 1B or 4) is met when over 150 net new trips are added to the intersection, or approximately 160 total single-family dwelling units. Traffic from approximately 120 additional residential units outside of the proposed project would be necessary to satisfy a signal warrant at the intersection. Mitigation Mitigation measures limited to the payment of transportation impact fees have been identified to reduce potential transportation-related project impacts. All site accesses operate at LOS C or better under existing and future AM and PM peak hour conditions. The 132nd Avenue NE/NE 100th Street intersection degrades from LOS E to LOS F with the addition of project traffic during the AM peak hour. This intersection operates at LOS F during the PM peak hour with or without the project. Signal warrants are not met at the 132nd Avenue NE/NE 100th Street intersection. Transportation Impact Fees The project would be required to pay the City’s Transportation Impact Fee. Per the City of Redmond Impact Fee2, the single-family dwelling unit fee is $6,771.67 per unit, resulting in an impact fee of approximately $237,010 for the 35-unit project. This fee is a preliminary calculation and the final impact fee would be calculated by the City of Redmond at the time of building permit issuance. 2 City of Redmond Impact Fees Schedule, January 2018. ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK---