TEXAS CITY PARK & RIDE RIDERSHIP ANALYSIS This document reviews the methodologies and tools used to calculate the projected ridership and parking space needs from the proposed Texas City Park & Ride to the Houston Central Business District (CBD), Texas Medical Center (TMC), and Galveston. Methodology The methodology used to determine parking demand for the proposed Texas City Park & Ride was developed by the Texas Transportation Institute (TTI) and is based on TTI s Procedures for Estimating Park-and-Ride Demand in Large Texas Cities. 1 The report outlines six methodologies to estimate park & ride demand. This report used the Modal Split methodology. The Modal Split methodology examines the home-based work (HBW) destinations for the market area population. The 2018 & 2025 H-GAC 4-Step Travel Demand Forecast (TDF) model, which is the federally funded regional TDF model, estimates the HBW trips from a production Traffic Analysis Zone (TAZ) to an attraction TAZ, which produces the H-GAC Production and Attraction (P&A) table. The TDF model accounts for future study area population, projected employment in Houston s downtown and other major activity centers, socioeconomic characteristics of study area residents, and travel time and cost characteristics of the competing highway and transit modes of travel. The model simulates travel on the entire highway and transit system in the Houston Metropolitan area, including all transit services provided by METRO (local bus, express bus, commuter bus, METRORail), Harris County Transit, Galveston Island Transit, Connect Transit, and future transit improvements contained in the area s Metropolitan Planning Organization (MPO) Long-Range Plan (LRP). The Modal Split methodology requires an analysis of the population and workers that will be served by the proposed facility, i.e., the population upstream of the facility given the ultimate downstream destination. Figure 1 illustrates that the typical park & ride service area (upstream) is parabolic in shape. However, the Figure 1 - Typical Park & Ride Market Area typical parabolic shape can be modified to account for the pattern of access provided by major arterial streets and freeways surrounding the park & ride, as well as for land use patterns (i.e., housing locations). The northbound and southbound market areas for the Texas City Park & Ride have been adapted in this manner and are shown in Figures 2 and 3, respectively. 1 TTI, Procedures for Estimating Park-and Ride Demand in Large Cities (1987). 1
Figure 2 - Texas City Park & Ride Northbound Market (Demand) Area 2
Figure 3 - Texas City Park & Ride Southbound Market (Demand) Area 3
Estimating Park & Ride Demand for the Texas City Park& Ride Facility Modal Split Methodology The TTI Modal Split method has four steps. The first step is to determine the TAZs to be included in the analysis by overlaying the market area boundary (parabola) on the TAZ boundaries, and also selecting the TAZs included in the destination area(s). The second step is to aggregate all the home-based work (HBW) trips from the market area to destination area(s). The third step is to determine an appropriate transit modal split to utilize for the HBW trips. Finally, the fourth step is to use the modal split to calculate the parking and ridership demand, based on the number of HBW trips traveling from the market area to the destination area(s). Step 1 The northbound and southbound market areas were selected as shown in Figures 2 and 3, respectively. The origin and destination TAZs were determined. Step 2 The total number of HBW trips from the market areas to the destination areas were determined. As previously noted, the H-GAC TDF model provides the trip generation and distribution output by estimating the number of trips from each TAZ to every other TAZ. Table 1 presents the total estimated HBW trips for 2018 and 2025 from the Texas City market areas to the northbound destination areas of the CBD and the TMC, and the southbound destination area of Galveston. Of the total HBW trips, only a percentage of the total trips would use public transportation. Table 1 - Total HBW from Texas City Market Areas to CBD, TMC, & Galveston Destination 2018 H-GAC TDF Model 2025 H-GAC TDF Model CBD 285 267 TMC 447 406 Galveston 7,072 7,130 Total 8,182 8,203 Step 3 The transit share of the total HBW trips for the proposed Texas City Park & Ride was estimated using H-GAC TDF model transit split data and known modal splits from existing regional park & rides. For HBW trips north to downtown Houston and the TMC, standard modal splits from the 2015 H-GAC TDF output were utilized. The modal split outputs for 2015, based on the current base transit network and no highway improvements, estimate that 37% would utilize transit to downtown Houston and 36% would utilize transit to the TMC. The modal split outputs for 2025, based on the current base transit network and the highway improvements included in the Regional Transportation Plan (RTP), estimate that 49% would utilize transit to downtown Houston and 38% would utilize transit to the TMC (Table 2). 4
Table 2 H-GAC TDF Modal Split Model Results (Northbound Service) Destination Modal Split for H-GAC HBW (Source: METRO Base Transit Network, Phase 2 Rail Network, No Highway Improvements) 2015 Modal Split for H-GAC HBW (Source: METRO Base Transit Network, Phase 2 Rail Network, Highway Improvements In RTP) 2025 CBD 37% 49% TMC 36% 38% For HBW trips south to Galveston, a modal split was estimated by analyzing known modal splits of the existing park & rides currently serving Galveston Victory Lakes and Mall of the Mainland. The Victory Lakes Park & Ride averaged approximately 367 passenger trips (boardings) per day in FY 2014. This equates to approximately 184 HBW trips. Using H-GAC s standard of 1.25 persons-pervehicle (PPV), the total number of parking spaces being utilized is approximately 147 per day. The H- GAC TDF model estimates 3,184 HBW trips from the Victory Lakes Park & Ride market area to Galveston in 2018. Based on these data, the average HBW trip transit share is approximately 6% (184/3,184). Note that the modal split may be a slightly low estimate, given that the total estimated HBW trips is provided for 2018 and not 2014. The Mall of the Mainland Park & Ride averaged approximately 93 passenger trips (boardings) per day in FY 2014. This equates to approximately 47 HBW trips. Using the same methodology discussed above for Victory Lakes, the estimated transit modal split is 2% (based on 2,210 total HBW trips from the Mall of Mainland Park & Ride market area). Again, the modal split may be a slightly low estimate due to the fact that the estimated total HBW trips are provided for 2018 rather than 2014. Table 3 presents the results of the modal split analysis for southbound service. Table 3 Southbound Service Modal Split Estimates 2014 Avg Park & Ride Boardings 2014 Avg HBW 2014 Parking Used 2018 Total HBW to Galveston Estimated Modal Split Mall of Mainland P&R 93 47 37 2,210 2% Victory Lakes P&R 367 184 147 3,184 6% Step 4 Based on the results of Step 3, estimated northbound transit modal splits of 38% and 36% to the CBD and TMC, respectively, and an estimated southbound modal split of 6.5% were used to project the ridership from the Texas City Park & Ride. Ridership will build to these levels over time as awareness and popularity of the service grows. The projected ridership and parking needs are presented in Tables 4, 5, and 6. 5
Table 4 Estimated Transit Ridership and Parking Demand to Downtown Houston Total HBW HBW Transit (Round ) Year Transit Share Year 1 (2018) 285 18.0% 51 102 41 Year 2 (2019) 282 23.0% 65 130 52 Year 3 (2020) 280 28.0% 78 156 63 Year 4 (2021) 277 33.0% 91 182 73 Year 5 (2022) 275 38.0% 104 208 83 Year 6 (2023) 272 38.0% 103 206 82 Year 7 (2024) 269 38.0% 102 204 82 Year 8 (2025) 267 38.0% 101 202 81 Year 9 (2026) 264 38.0% 100 200 80 Year 10 (2027) 262 38.0% 99 198 79 Table 5 Estimated Transit Ridership and Parking Demand to TMC Total HBW HBW Transit (Round ) Year Transit Share Year 1 (2018) 447 18.0% 80 160 64 Year 2 (2019) 441 22.5% 99 198 79 Year 3 (2020) 435 27.0% 118 236 94 Year 4 (2021) 429 31.5% 135 270 108 Year 5 (2022) 424 36.0% 152 304 122 Year 6 (2023) 418 36.0% 150 300 120 Year 7 (2024) 412 36.0% 148 296 118 Year 8 (2025) 406 36.0% 146 292 117 Year 9 (2026) 400 36.0% 144 288 115 Year 10 (2027) 394 36.0% 142 284 114 Table 6 Estimated Transit Ridership and Parking Demand to Galveston Total HBW HBW Transit (Round ) Year Transit Share Year 1 (2018) 7,072 2.00% 141 282 113 Year 2 (2019) 7,080 2.50% 177 354 142 Year 3 (2020) 7,089 3.00% 213 426 170 Year 4 (2021) 7,097 3.50% 248 496 199 Year 5 (2022) 7,105 4.00% 284 568 227 Year 6 (2023) 7,114 4.50% 320 640 256 Year 7 (2024) 7,122 5.00% 356 712 285 Year 8 (2025) 7,130 5.50% 392 784 314 Year 9 (2026) 7,138 6.00% 428 856 342 Year 10 (2027) 7,147 6.50% 465 930 372 6
Summary Table 7 presents the total ridership and parking demand generated by northbound service to the CBD and TMC, and southbound service to Galveston from the Texas City Park & Ride. Annual passenger trips are based on 260 operating days per year. Table 7 Summary of Demand Analysis HBW Transit (Round ) Annual Year Year 1 (2018) 272 544 141,440 218 Year 2 (2019) 341 682 177,320 273 Year 3 (2020) 409 818 212,680 327 Year 4 (2021) 474 948 246,480 380 Year 5 (2022) 540 1,080 280,800 432 Year 6 (2023) 573 1,146 297,960 458 Year 7 (2024) 606 1,212 315,120 485 Year 8 (2025) 639 1,278 332,280 512 Year 9 (2026) 672 1,344 349,440 537 Year 10 (2027) 706 1,412 367,120 565 7