Measuring Rail Transit's Sustainability Goals: A Before-After, Experimental-Control Evaluation of Los Angeles' Expo Light Rail Line

Transcription

1 Measuring Rail Transit's Sustainability Goals: A Before-After, Experimental-Control Evaluation of Los Angeles' Expo Light Rail Line Marlon G. Boarnet Professor, USC Sol Price School of Public Policy and co-pi s and Researchers: Doug Houston (UC Irvine), Steve Spears (Univ. of Iowa), Andy Hong (Univ. of British Columbia), Xize Wang (USC)

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3 Changing Times Transportation used to be this: But has become this: Source: KCET SoCal Focus, carmageddon-a-photographic-look-at-the-construction-of-5-socal-freeways html Sources: : and Western Riverside Council of Governments.

4 Research for an Era of Locally Innovative Transportation High occupancy toll lanes Real time parking pricing Bicycle sharing Neighborhood electric vehicles Pedestrian mall Traffic calming Employer provided transit pass Los Angeles rail transformation Six new lines opening between 2012 and 2020 Expo Line Phase I is the first of the six When complete: Los Angeles MTA rail system will be larger than Washington Metro California Senate Bill 375 (2008) SCAG: 8% reduction by 2020; 13% reduction by 2035

5 How do we know what works? Program Evaluation Before-After, Experimental-Control Group study of rail transit impact Motivation: Better evidence on causal impact of rail Estimate of magnitude of impact Pilot test program evaluation more generally Previous similar studies in: Charlotte (McDonald et al., 2010) Salt Lake City (Brown and Werner, 2008) Seattle (in progress, Saelens et al., U of Washington)

6 Evaluating the Experiment: The Expo Line Source: Google Maps Phase I, opened April 28, 2012 (Culver City station opened June 20, 2012) Source: L.A. Metro

7 Study Area Selection, Summer 2011

8 Survey Waves Wave 1, Sept., 2011 Jan (3 to 7 months before opening) 284 households Wave 2, Sept., 2012 Jan (5 to 8 months after opening) 204 households as of Dec. 20, 2012 A true panel study; only households from Wave 1 recontacted Wave 3, fall 2013 (174 households)

9 Study Subjects

10 Survey Methods 7-day travel diary, all household members 12 and older Household and individual sociodemographics Income, car ownership, etc. Attitudes toward environment, safety In 141 households (Wave 1), 1 adult carried a GPS and accelerometer

11 Survey Methods

12 Survey Methods

13 Dependent Variables Self-Reported: Daily VMT (for HH and persons in HH) Daily # of car trips (for HH and person, driver and passenger) Daily transit trips bus and rail transit Daily walk trips Daily bike trips Daily walk minutes Daily bike minutes Plus: Accelerometer moderate-vigorous PA minutes GPS trace (route)

14 Study Design Experimental (Treatment) Experimental (Treatment) Experimental (Treatment) Difference in travel behavior, Wave 3 Difference in travel behavior, Wave 2 Difference in travel behavior, Wave 1 Control Group Control Group Control Group Wave 1 (6 mo s before opening) N = 284 households Wave 2 (6 mo s after opening) N = 204 households Wave 3 (6 mo s after opening) N = 174 households Effect of Expo Line on Travel Behavior (Treatment Effect)

15 Wave 1 and 2 Data Wave 1 and Wave 2 data Response Complete Type Responses Mobile Tracking 106 Self-Report only 98 Total 204 Group Control 101 Experimental 103 Total 204

16 Before Expo Line Opened: No Experimental- Control Differences in Travel Comparison of Expo Before Opening and NHTS Expo Line Study Area NHTS within Study Area NHTS LA County Travel Outcome Variable mean N mean N mean N Daily Vehicle Miles Traveled Daily Car Trips (Driver+Passenger) Daily Bus Trips Daily Train Trips Daily Transit Trips Daily Bike Trips Daily Walk Trips

17 After Expo Line Opened: Big Drop in Driving in Experimental Group VMT Train trips Total Transit Trips Study Group 6 months before 6 months after 18 months after Mean Mean Diff. t Sig. Mean Mean Diff. t Sig. Mean exp control exp ** control exp control Significance codes: ** < 0.01, * < 0.05, < 0.10 Note: All values are per household daily trip frequencies or VMT. Mean Diff. t Sig * *

18 And the experimental group rode rail more VMT Train trips Total Transit Trips Study Group 6 months before 6 months after 18 months after Mean Mean Diff. t Sig. Mean Mean Diff. t Sig. Mean exp control exp ** control exp control Significance codes: ** < 0.01, * < 0.05, < 0.10 Note: All values are per household daily trip frequencies or VMT. Mean Diff. t Sig * *

19 Same results controlling for number of persons in the household, number of vehicles, and income Travel Outcome 6 mo. After t Sig. 18 mo. After t Sig. N VMT * 435 Car Driver Trips Car Passenger Trips Bus Trips Train Trips Total Transit Trips Active (Walk + Bike) Trips Total Trips Significance Codes: * < 0.05, < 0.10

20 Why? (1) Rail Riders Reduce Car Trip Length 6 Months Before Opening 6 Months After Opening 18 Months After Opening Train Users (n = 16, 9.3%) Non-train Users (n =156, 90.7%) Train Users (n = 32, 18.7%) Non-train Users (n =139, 81.3%) Train Users (n = 35, 20.3%) Non-train Users (n = 138, 79.7%) Mean Mean Sig. Mean Mean Sig. Mean Mean Sig. Car Trip Length * Cars Available ** Household Income ($1,000) ** Significance Codes: *** < 0.001, ** < 0.01, * < 0.05, < 0.10

21 Why? (2) Rail Riders Became More Like Non-Riders 6 Months Before Opening 6 Months After Opening 18 Months After Opening Train Users (n = 16, 9.3%) Non-train Users (n =156, 90.7%) Train Users (n = 32, 18.7%) Non-train Users (n =139, 81.3%) Train Users (n = 35, 20.3%) Non-train Users (n = 138, 79.7%) Mean Mean Sig. Mean Mean Sig. Mean Mean Sig. Car Trip Length * Cars Available ** Household Income ($1,000) ** Significance Codes: *** < 0.001, ** < 0.01, * < 0.05, < 0.10

22 Shorter Car Trips are More Important than Rail Displacing Car Trips 1. Rail Trips Displace Car Trips Effect Size Car Trip Length Effect Calculation Effect trips per day 9.37 miles/trip 9.37 miles/trip * 0.21 trips daily per day miles Change in rail trips 2. Car Trips Get Shorter experimental, Wave 1, car trip length Effect Size Penetration Effect Calculation Effect miles/trip 20.30% penetration (20.3%) * effect size (-6.92 miles/trip) * number of car trips (3.3 car trips per day, experimental, before opening) Change in car trip length for rail riders Fraction rail riders among experimental group daily miles Fraction of Total VMT Reduction 19.95% 48.13% Fraction of 9.87 household miles per day VMT reduction

23 Results Daily household VMT drops by about 10 miles per day (average for study group 27 miles per day) VMT drop (relative to control group) persists in Wave 3, more than 1 year after opening Increases in rail trips (more than doubled), experimental vs. control Two thirds of the VMT reduction can be attributed to shorter car trips and eliminated driving trips among rail riders

24 Learn More Final Report to Haynes Foundation Final Report to Lincoln Institute of Land Policy Final Report to USC Lusk Center for Real Estate Refereed Articles: New light rail transit and active travel: A longitudinal study A Hong, MG Boarnet, D Houston Transportation Research Part A: Policy and Practice 92, Driving reduction after the introduction of light rail transit: Evidence from an experimental-control group evaluation of the Los Angeles Expo Line S Spears, MG Boarnet, D Houston, Urban Studies CAN NEW LIGHT RAIL REDUCE PERSONAL VEHICLE CARBON EMISSIONS? A BEFORE AFTER, EXPERIMENTAL CONTROL EVALUATION IN LOS ANGELESMG Boarnet, X Wang, D Houston, Journal of Regional Science

25 Thank you to: Our funders: California Air Resources Board Haynes Foundation Lincoln Institute of Land Policy Robert Wood Johnson Foundation (accelerometers) San Jose State Mineta Transportation Institute Southern California Association of Governments UC Transportation Center UC Multi-Campus Research Program on Sustainable Transportation USC Lusk Center for Real Estate Our team members: Doug Houston, UC Irvine, co-pi Steve Spears, project manager Research assistants: UC-Irvine Ph.D. students: Dongwoo Yang, Gavin Ferguson, Hsin-Ping Hsu, Gaby Abdel-Salam USC Ph.D. students: Andy Hong, Xize Wang, Sandip Chakrabarti, Jeongwoo Lee Translation: Carolina Sarmiento and Grecia Alberto Field research assistance: Grecia Alberto, Priscilla Appiah, Gabriel Barreras, Dafne Gokcen, Adrienne Lindgren, Boyang Zhang, Cynthia de la Torre, Owen Serra, Lisa Frank, Greg Mayer, Vicente Sauceda