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HomeMy WebLinkAbout005.01 - Appendix D.1 - Trip_Gen_Addendum December 18, 2024 Mr. Sam Kendall Jackadoo, LP Brick Capital 1907 Pine Street Philadelphia, PA 19103 Reference: Block 104 Traffic Impact Study, Trip Generation Update Project No. 06020.11 Dear Mr. Kendall, The purpose of this letter is to provide an addendum to the Block 104 Traffic Impact Study (TIS) to meet the requests set forth by the City of Bozeman. The TIS was originally completed by Sanbell (formerly Sanderson Stewart) in December of 2023. It was requested by the City that updated trip generation calculations be performed to account for the planned commercial space on the first floor of the south building. The total number of residential units has been reduced since completion of the original TIS, so it will be presented that the net change in trip generation for the development is insignificant and therefore the findings from the original TIS are still applicable. The updated site plan for Bozeman Yards proposes 26 units in the north building and 42 units in the south building for 68 total dwelling units, with 1,759 square-feet of commercial retail use also in the south building. The original Block 104 TIS proposed 76 total residential dwelling units. The updated trip generation calculations utilized Trip Generation, 11th Edition published by the Institute of Transportation Engineers (ITE), which is the most widely accepted source in the United States for determining trip generation projections. Multifamily Housing (Mid-Rise) (Land Use Code 221) and Strip Retail Plaza (<40k) (Land Use Code 822) were used to project trip generation for the Bozeman Yards site. Table 1 on the following page illustrates the results of the trip generation calculations, including a comparison to the original Block 104 total trip projections. Mr. Sam Kendall December 18, 2024 Page 2 With the updated residential unit totals and commercial space, the Bozeman Yards site is projected to generation 407 gross average weekday trips, with 29 trips (8 entering/21 exiting) generated during the AM peak hour and 39 trips (22 entering/17 exiting) generated during the PM peak hour. Trip generation projections provide an estimate of the total number of trips that would be generated by a proposed development. However, in order to estimate the net number of new trips made by personal vehicles external to the site, adjustments must often be made to account for internal capture trips, pass-by trips, and trips made by alternate modes. Internal capture (IC) trips are trips that do not have origins or destinations external to a project site and therefore do not have an impact on external traffic operations. IC trips most often occur in mixed-use developments where residential, commercial, and office-related land uses exhibit a high rate of internal trip exchange. IC trips were therefore calculated between the residential units and the proposed commercial space. Pass-by trips are trips that are made as intermediate stops on the way from a point of origin to a primary trip destination. Pass-by trips are attracted from traffic “passing by” on an adjacent street that offers direct access to the site. Pass-by trips are Table 1: Updated Trip Generation Summary Intensity Units total enter exit total enter exit total enter exit Multifamily Housing (Mid-Rise)1 76 Dwelling Units 345 173 172 28 6 22 30 18 12 Multifamily Housing (Mid-Rise)1 68 Dwelling Units 309 155 154 25 6 19 27 16 11 17 10 7 0 0 0 3 2 1 Strip Retail Plaza (<40k)2 1.795 1000 SF GFA 98 49 49 4 2 2 12 6 6 17 7 10 0 0 0 3 1 2 407 204 203 29 8 21 39 22 17 34 17 17 0 0 0 6 3 3 373 187 186 29 8 21 33 19 14 28 14 14 1 2 -1 3 1 2 (1) Multifamily Housing (Mid-Rise) - Land Use 221* Units = Dwelling Units Average Weekday: Average Rate = 4.54 (50% entering/50% exiting) Peak Hour of the Adjacent Street, One Hour between 7 and 9 AM: Average Rate = 0.37 (23% entering/77% exiting) Peak Hour of the Adjacent Street, One Hour between 4 and 6 PM: Average Rate = 0.39 (61% entering/39% exiting) (2) Strip Retail Plaza (<40k) - Land Use 822* Units = 1000 Sq. Ft. GFA Average Weekday: Average Rate = 54.45 (50% entering/50% exiting) Peak Hour of the Adjacent Street, One Hour between 7 and 9 AM: Average Rate = 2.36 (60% entering/40% exiting) Peak Hour of the Adjacent Street, One Hour between 4 and 6 PM: Average Rate = 6.59 (50% entering/50% exiting) *Trip Generation, 11th Edition, Institute of Transportation Engineers, 2021 **Trip Generation Handbook, 3rd Edition, Institute of Transportation Engineers, 2017 Independent Variable Average Weekday Bozeman Yards Gross Trips PM Peak HourLand Use AM Peak Hour Internal Capture Trips** Internal Capture Trips** Bozeman Yards Internal Capture Trips Bozeman Yards New External Trips Net New External Trips Updated Bozeman Yards Proposed Land Uses Original Block 104 TIS Trip Generation Mr. Sam Kendall December 18, 2024 Page 3 primarily attracted by commercial type land uses such as restaurants, convenience markets, and gas stations. Although pass-by trips often occur at commercial uses, ITE does not provide pass-by rates for the land use assumed in this analysis. Therefore, no pass-by reductions were assumed. A portion of external trips generated by the development could be made by alternate modes (walking, biking, and transit), thereby reducing vehicular trips generated. There are bike lanes, sidewalks, and/or multi-use paths accessing the site from most directions but, to be consistent with the original TIS, alternate mode trips were conservatively assumed to be negligible for the purposes of this study. When comparing the new trip generation projections for the Bozeman Yard site to the original Block 104 TIS, it was found that 28 additional daily trips are projected with the updated land uses. In the AM peak hour, 1 net additional trip is projected (2 entering/-1 exiting) and 3 net additional trips are projected in the PM peak hour (1 entering/2 exiting). This corresponds to an increase of 8 percent in total daily trips, 4 percent in AM peak hour trips, and 10 percent in PM peak hour trips. The above values are negligible when compared to the total trip generation and would not alter the analysis or results presented in the original Block 104 TIS. Therefore, the updated land use projections are adequately represented by the original TIS and all findings presented therein remain relevant and should be implemented. If you have any questions or concerns, please feel free to contact me at 406-922-4326 or jstaszcuk@sanbell.com. Sincerely, Joey Staszcuk, PE, PTOE, RSP1 Associate Principal | Community Transportation Studio Manager ARS/jhs/SG P:06020.11_Block_104_Update_12.18.2024