Impact of Carpool Tolls on Bay Bridge Casual Carpooling A Case Study

Transcription

1 Impact of Carpool Tolls on Bay Bridge Casual Carpooling A Case Study Elizabeth Deakin Professor of City and Regional Planning and Urban Design University of California, Berkeley May 24, 2012

2 2010 Increase in the San Francisco-Oakland Bay Bridge Tolls Weekday Peak AM, Weekday Off-Peak Carpool lanes 5-10AM, Weekends 3-7PM 3-7PM only BEFORE 7/1/10 AFTER 7/1/10 $4.00 $4.00 Free $4.00 $6.00 $4.00 $2.50* $5.00 *Must be 3+; after 7/1/10 must have FasTrak 30

3 Study Design Part of an independent evaluation of the Bay Bridge toll changes conducted for the Bay Area Toll Authority (Deakin, Frick, Cervero and Skabardonis, Nov. 2011) Question for this paper: how were casual carpoolers affected by the imposition of a toll? Data for this portion of the study included: carpool lane usage data before and after the toll increase Surveys of casual carpoolers before and after Surveys of FasTrak holders (carpools and others) from BATA list Survey of casual carpoolers (recruited from sites) Eight focus groups with carpoolers and former carpoolers (>100 participants, who also filled out a survey)

4 Background lane Bridge carries ~288,000 vehicles, 590,000 people/ day Tolls collected westbound only Increase was to help pay for bridge projects, but also serves as a mild form of congestion pricing $2 peak toll increase is a small portion of average round trip cost by car, which can range from $10 to $ would expect modest response Bridge exhibits high day to day & seasonal traffic variability, accentuated by recession Construction projects on Bridge & routes leading to bridge Changes in transit LOS and costs in same corridors Both casual carpooling and pre-arranged carpooling; total was declining before toll increase Many carpoolers have transit options casual carpoolers often catch rides from transit stations

5 Affects of the Toll Increases: Before and After Bay Bridge Annual Average Daily Traffic (work days) Lane Group Before Toll Increase After Toll Increase Vehicle difference Cash/ FasTrak Lanes 108, ,420 3,310 Carpool Lanes 16,900 12,535 (4,365) Total 125, ,955 (1,055) Source: BATA data 33

6 What the Toll Accomplished Peak period toll increase led to less congestion at the Bridge approaches, am peak time savings of 5-10 min. for many Net effects on bridge traffic were minimal (but it doesn t take a big shift to reduce impacts) Bay Bridge carpool lane volumes dropped ~26% & Cash/FasTrak volumes went up by ~ 3%. 34

7 How to Measure Carpool Changes? Media reports: Carpooling down drastically 26%-33% decline. Alternative interpretation: carpool lane use down ~5%, but more transit use and offpeak travel as expected What still wasn t known: What happened to the carpools?

8 What Happened to the Carpools? Possible Explanations Toll discouraged carpooling, especially casual --More driving alone (Media coverage emphasized this) BUT there may be some additional explanations: Two person carpools in full fare lanes decline in occupancy but not total loss Cheaters were scared out of HOV lanes by FasTrak cameras Some shifted out of peak to avoid FasTrak or toll BART attracted more riders Carpooling was down because of high gas prices, unemployment, economic worries

9 Traffic Volumes Don t Offer a Simple Answer HOV lane counts down vehicles (depending on when counts done) At 3 people per vehicle: up to 15,000 people were affected If riders all became solo drivers, there would be as many as 10,000 more vehicles in the cash/fastrak lanes BUT only ~3,000 more vehicles in the cash/fastrak lanes So most former users of HOV lanes did NOT become drivealone bridge crossers Where did they go? 37

10 Key Factors Influencing Carpool Lane Traffic Volume Decreases 1 st Pass Using Regional Datasets Other includes: changes in economic conditions, social relationships between carpoolers, changes in travelers personal circumstances and additional factors Source: Cervero analysis for Bay Bridge Study 38

11 Findings from Surveys and Focus Groups Different markets for casual carpooling motivations and reactions different Some want to save money Some want to save time Some want to help others out Some just think it s fun and a little counter-cultural Carpool toll wasn t understood - adding a toll was considered a signal of loss of public support - any toll at all is considered a barrier

12 More Findings Toll changed social dynamics in casual carpools, created discomfort Negotiating contributions proved awkward, sometimes contentious (but settled into place after a while) Brought motives for acts of generosity into question Changed free-spirited adventure into commercial transaction Cost sharing now varies by location: $1.25 for Vallejo (2 bridges) $1 at some other East Bay sites No toll accepted at other locations (or hit or miss)

13 More Findings Some returned to BART many casual carpoolers had always used BART to return home, or as backup even a little hassle was enough to shift many back to BART full time Family twosomes most likely to quit offering rides - effort to get one more person not worth complications, esp. since traffic is better Some are going earlier or later to avoid toll and not have the hassle Very few changed destinations ( For two bucks?? Nah ) who are reluctant to continue with FasTrak, cameras, etc. (small number?)

14 And Still More Findings! Support for formally organized carpooling (matching assistance, incentives) has waned, reducing the attractiveness of the option ( you re on your own ) this is a partial explanation for shifts Many employers have discontinued commute assistance programs Some employers now use commuter check instead of staffed office to assist commute alternatives AND : Some were indeed cheaters who got scared off by a toll and cameras NOTE: these are what could be called a last straw effect: people already questioning their travel behavior are pushed to act

15 Summary What happened to carpoolers? Most are still out there carpooling! Some decided to drive to work alone or in twoperson carpools, but many others went to transit and some chose to travel off-peak. Casual carpooler reactions were as much to the existence of a toll as to the dollar amount this is consistent with their emphasis on the social dynamics Can t just analyze these changes as a simple economic phenomenon 43

16 Additional Research Team Members Co-Authors of Reports and Working Papers: Karen Frick, Robert Cervero, Alex Skabardonis, James Rubin, Ian Barnes, Karla Kingsley, Eric Jensen, Javier Amaro Additional Contributors: Cindy Sun, Jennifer Wong, Melanie Curry, Andreanna Tzortzis, Nathan Machida 44