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1130 SW Morrison St., Suite 318 Portland, OR 97205 [PHONE REDACTED] lancastermobley.com Memorandum To: City of Woodburn Copy: Sarah Rose, AC + Co Architecture Community From: Melissa Webb, PE Date: May 12, 2025 Subject: Contractor Storage Building – Trip Generation Memorandum Introduction This memorandum reports and evaluates the transportation impacts related to the addition of a contractor storage building, located at 669 Ray J. Glatt Circle in Woodburn, Oregon. The proposed redevelopment includes the construction of a 14,110 square foot construction office and warehouse in the southern portion of the lot (Phase and an additional 4,780 square foot office expansion building just south of an existing facility (Phase The purpose of this memorandum is to examine the projected trip generation of the proposed redevelopment for the morning peak hour, evening peak hour, and average weekday. Based on the trip generation projections, the City of Woodburn’s and ODOT’s impact thresholds for requiring a full Transportation Impact Analysis (TIA) will be evaluated. Project Location & Description The project site is located on tax lot number 051W07AC03500 and is situated east of N Boones Ferry Road, west of Ray J. Glatt Circle, and north of OR-214 in Woodburn, Oregon. The property encompasses approximately 2.08 acres and has two existing buildings on-site, which will remain upon redevelopment of the property. Access to the site is currently taken from existing access driveways along Ray J. Platt Circle and N Boones Ferry Road. An aerial view of the project site and the nearby vicinity is shown in Figure 1, with the subject site outlined in yellow. In addition, a site plan is attached to this memorandum. Melissa A Webb Digitally signed by Melissa A Webb Date: 2025.05.12 08:57:55 -07'00' ---PAGE BREAK--- May 12, 2025 Page 2 of 4 Figure 1: Site Location (image from Google Earth) Trip Generation The proposed redevelopment will include two phases. Phase 1 will include the construction of a 14,110 square foot construction office and warehouse in the southern portion of the lot, and Phase 2 will include the construction of an additional 4,780 square foot office expansion building north of the Phase 1 facility. There are two existing buildings on the north end of the site that will remain upon redevelopment. Since the size and land use of these facilities is not expected to change upon redevelopment of the site, these existing facilities were assumed to have no change in trip generation. To estimate the number of trips that will be generated by the proposed redevelopment, trip rates from the Trip Generation Manual 1 were used. Phase 1 will consist of a facility for office space as well as a warehouse storage area. Therefore, data from land use codes 150, Warehousing, and 712, Small Office Building, were used to estimate the Phase 1 development’s trip generation based on the square footage of gross floor area. Phase 2 will consist of a facility for the expansion of office space: therefore, data from the land use code 712, Small Office 1 Institute of Transportation Engineers (ITE), Trip Generation Manual, 11th Edition, 2021. ---PAGE BREAK--- May 12, 2025 Page 3 of 4 Building, was used to estimate the Phase 2 development’s trip generation based on the square footage of gross floor area. The resulting trip generation estimates are summarized in Table 1. Detailed trip generation calculations are included as an attachment to this memorandum. Table 1: Trip Generation ITE Code Intensity Morning Peak Hour Evening Peak Hour Daily Trips In Out Total In Out Total Proposed Redevelopment Phase 1 150 - Warehousing 4,614 SF 1 0 1 0 1 1 8 712 – Small Office Building 9,496 SF 13 3 16 7 14 21 137 Total Phase 1 14,110 SF 14 3 17 7 15 22 145 Phase 2 712 - Small Office Building 4,780 SF 7 1 8 4 6 10 69 Net Increase in Primary Trips (Phase 1 & 2) 21 4 25 11 21 32 214 The trip generation calculations show that the proposed redevelopment is projected to generate up to 25 additional morning peak hour trips, up to 32 additional evening peak hour trips, and up to 214 additional average weekday trips. Transportation Impact Analysis Requirements The Woodburn Development Ordinance (WDO) section 3.04.05 states a TIA is required if a development generates 50 or more peak hour trips or 500 or more average daily trips (ADT). Additionally, per Table 3.2: TIA Threshold and Analysis Areas in ODOT’s Development Review Guidelines 2, a TIA would be necessary if the proposed development were to generate 50 morning or evening peak hour trips, or 300 average daily trip impacts to ODOT intersections. Based on the trip generation estimates provided in Table 1, the proposed development generates less than 50 peak hour trips and less than 300 ADT. Therefore, a TIA is not required as part of the proposed development application. 2 Oregon Department of Transportation, Development Review Guidelines, 2017. ---PAGE BREAK--- May 12, 2025 Page 4 of 4 Conclusions The proposed redevelopment is not projected to trigger the City of Woodburn’s or ODOT’s trip impact thresholds requiring the need for a full TIA. Therefore, the construction and occupancy of the proposed buildings is not expected to create significant impacts to the transportation system, whereby this trip generation analysis memorandum is sufficient to capture the trip impacts of the proposed development. Attachments Site Plan Trip Generation ---PAGE BREAK--- ---PAGE BREAK--- Land Use: Land Use Code: Land Use Subcategory: Setting/Location Variable: Trip Type: Formula Type: Variable Quantity: 15 Trip Rate: 0.17 Trip Rate: 0.18 Enter Exit Total Enter Exit Total Directional Split 77% 23% Directional Split 28% 72% Trip Ends 1 0 1 Trip Ends 0 1 1 Trip Rate: 1.71 Enter Exit Total Directional Split 50% 50% Trip Ends 4 4 8 Source: Trip Generation Manual, 11th Edition WEEKDAY 1000 SF GFA Vehicle Rate 4.6 AM PEAK HOUR PM PEAK HOUR General Urban/Suburban TRIP GENERATION CALCULATIONS Proposed Redevelopment - Phase 1 Warehousing 150 All Sites ---PAGE BREAK--- Land Use: Land Use Code: Land Use Subcategory: Setting/Location Variable: Trip Type: Formula Type: Variable Quantity: Trip Rate: 1.67 Trip Rate: 2.16 Enter Exit Total Enter Exit Total Directional Split 82% 18% Directional Split 34% 66% Trip Ends 13 3 16 Trip Ends 7 14 21 Trip Rate: 14.39 Enter Exit Total Directional Split 50% 50% Trip Ends 69 69 137 Source: Trip Generation Manual, 11th Edition WEEKDAY TRIP GENERATION CALCULATIONS AM PEAK HOUR PM PEAK HOUR Small Office Building All Sites 9.5 WARNING: Variable Quantity is greater than Maximum Survey Size for Peak Hours Proposed Redevelopment - Phase 1 712 General Urban/Suburban 1000 SF GFA Vehicle Rate ---PAGE BREAK--- Land Use: Land Use Code: Land Use Subcategory: Setting/Location Variable: Trip Type: Formula Type: Variable Quantity: Trip Rate: 1.67 Trip Rate: 2.16 Enter Exit Total Enter Exit Total Directional Split 82% 18% Directional Split 34% 66% Trip Ends 7 1 8 Trip Ends 3 7 10 Trip Rate: 14.39 Enter Exit Total Directional Split 50% 50% Trip Ends 35 34 69 Source: Trip Generation Manual, 11th Edition WEEKDAY 1000 SF GFA Vehicle Rate 4.8 AM PEAK HOUR PM PEAK HOUR TRIP GENERATION CALCULATIONS Proposed Redevelopment - Phase 2 Small Office Building 712 All Sites General Urban/Suburban