MIXED METHODS OF BIKE COU TI G FOR BETTER CYCLI G STATISTICS: THE EXAMPLE OF BICYCLE USE, ABA DO ME T, A D THEFT O THE UC DAVIS CAMPUS

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1 0 MIXED METHODS OF BIKE COU TI G FOR BETTER CYCLI G STATISTICS: THE EXAMPLE OF BICYCLE USE, ABA DO ME T, A D THEFT O THE UC DAVIS CAMPUS Kristin Lovejoy Student, Institute of Transportation Studies University of California, Davis One Shields Avenue Davis, CA kelovejoy@ucdavis.edu Susan Handy Director, Sustainable Transportation Center Professor, Environmental Science and Policy University of California, Davis One Shields Avenue Davis, CA slhandy@ucdavis.edu August,, words + figures =, words ABSTRACT The paper describes using a combination of different methods of bike counting to better understand volumes of bicycles, bicyclists, and bicycle thefts at UC Davis. In particular, police reports and bike rack counts were combined with surveying a random sample of the population in order to triangulate around total numbers of active versus abandoned bikes parked on campus, net movements of bikes over the course of a day, and the extent that bikes were being used as local circulator mode only and whether they were being stored on campus overnight. The results underscore the value of using a mix of different measurement methods, enabling UC Davis planners to better estimate the volume of abandoned bikes parked on campus (approximately percent of overnight bikes, percent of daytime bikes, and percent of the overall rack capacity), the extent that bicycle thefts are underreported (about percent are reported), and the extent that bikes are used as a secondary circulator mode (about percent of the bikes on campus on an average weekday). TRB Annual Meeting

2 0 0 0 MIXED METHODS OF BIKE COU TI G FOR BETTER CYCLI G STATISTICS: THE EXAMPLE OF BICYCLE USE, ABA DO ME T, A D THEFT O THE UC DAVIS CAMPUS. I TRODUCTIO.. Motivations for Measuring Bicycle Use Many city planners are interested in measuring mode split, whether along a given corridor, or for certain types of trips, or for all travel in a given region. As a destination for approximately 0,0 people on a daily basis, the University of California at Davis (UC Davis) functions as an entity that is almost like a small city, with travel to and from campus comprising a major part of overall travel in the region. Measuring the mode split for travel to UC Davis is especially relevant because of the university s and city s historical role in promoting bicycles (see, ). In the 0s and 0s, university leadership opted to close the core campus to cars, to provide ample bike parking and bike paths, and generally prioritize bicycles as a mode of travel. Davis is famed for having the first bicycle lanes in the United States and with its extensive network of bikeways and bike lanes, receives a top platinum rating from the League of American Bicyclists for bicycle friendliness (along with Portland, Oregon and Boulder, Colorado). However, there has been little tracking of cycling rates over time as the city and the university continue to grow. An increasing share of city residents traveling to points outside of Davis for work and shopping and an increasing share of UC Davis affiliates (students and staff) commuting to Davis from outside of town both serve to dampen levels of cycling in Davis. Renewed interest in promoting cycling motivated campus planners to begin tracking the overall level of cycling (and mode split for campus travel) in 0. In order to adequately plan for and manage bicycling in Davis, the city and the campus need data not just on the volume of bicycling but also on several related aspects of bicycling. For instance, campus maintains parking facilities consisting of varied types of racks plus a few lockers with an overall capacity for about,000 bicycles. As at many other universities and cities, perhaps especially those with a substantial volume of cyclists, bike theft is a major problem at UC Davis. The university is interested in tracking and diminishing the overall volume of thefts. In addition, with approximately percent turnover of the overall campus population each year, there is extensive bike abandonment on campus. With restrictions on the handling of abandoned bikes, which are legally considered abandoned property on land that is owned by the state of California, their removal is a burden. In addition, they take up space on campus bike racks and contribute visual clutter. (See the campus s policy regarding abandoned bikes online here Knowing the total volume of abandoned bikes is difficult but is needed for assessing the scope of the problem. While it is perhaps counterintuitive, theft and abandonment go hand-in-hand to some extent, since the large volume of idle, unwatched often poorly secured bicycles provide temptation for thieves and since the fear of theft inhibits people from investing in high-quality bicycles; the low-quality bicycles that end of being people s campus bike are more likely to be neglected, to break down, treated as disposable, and perhaps eventually abandoned altogether. Both phenomena affect the quality of the experience of bicycling in Davis and therefore may potentially impact the overall levels of cycling in the long run... Different Methods for Measuring Bicycle Activity Below is a description of some of the different methods of measuring volumes of bicycles, bicyclists, and incidents involving bikes. Each has pros and cons and produces slightly different type of information, as summarized below. Traffic Counts Perhaps the most common way of counting bikes, traffic counts are counts of the number of cyclists passing a particular point on a particular route or at an intersection. These counts may be done manually by a person watching and counting or using an automated bike counter (for a review of these, see ). Both methods are employed in cities such as Portland and San Francisco (, ). An advantage of manual counts is ability to measure other types of information about each cyclists and/or particular cycling behavior, such as gender, helmet, wrong-way riding, passing, etc. An advantage of TRB Annual Meeting

3 0 0 0 automated counters is the ability to collect continuous data over a longer period of time, for overall flows throughout the day, for instance. Any sort of traffic count (manual or automated), however, can only give information about traffic at the particular location where the count is conducted. This can be an indicator of overall volumes citywide, as increases on major corridors probably indicate increases in cycling more generally, but are not designed to capture the overall mode split for a city. This sort of count also gives no information about cyclists origins or destinations, parking, or storage habits. Rack Count (Snapshot at Fixed Point in Time) A count of bicycles parked in a particular facility, this sort of count is oriented to examining the numbers of bikes (and presumably cyclists) at a particular destination at a fixed point in time. An advantage of this sort of count is that it enables accounting of all bikes, regardless of the route chosen to reach the destination of interest, rather than trying to capture all possible points of entry in a traffic count. It is especially useful for giving information on the extent that particular bike parking facilities are utilized. It can also be done fairly quickly and at any point in time between (probably between the expected morning and evening peak periods of travel), rather than something that has to be measured during the peak period of travel. A disadvantage is that it gives no information about the owners of the bikes (such as gender, helmet use, or whether there is indeed one owner per bicycle), their arrival time or date (perhaps the bike has been sitting there for days), their origin (for instance, the presence of a bike may indicate a commute to that location has taken place or that a bike is permanently stored there), or gross volumes (if there is a lot of turnover over the course of the day, gross volumes would be greater than snapshot counts). Rack Inventory (Tracking of Gross Volumes over an Interval of Time) More involved observations of racks might include real-time accounting for all the bikes that come and go during a particular interval of time. This offers the same advantages of the snapshot count above, plus the added information of gross volumes and the opportunity to collect more information about the cyclists themselves (for instance gender or helmet use). However unless automated, it is more labor-intensive as well, and still suffers from some of the other shortcomings of snapshot rack counts. Official Records of Incidents Police or hospital records can be used as a source of data on the number of bike-related injuries, thefts, or other incidents. An advantage of this source of data is that it is standardized, objective, and often readily available. A disadvantage is that bike accidents and bike thefts are generally under-reported, and so the count is not thought to be complete. In addition, these sorts of records tell nothing of exposure levels, that is, the how the number of incidents compares to the amount of cycling, or number of cyclists, that exist. Travel surveys A survey of households or of employees about their overall travel patterns, in the form of a diary or some other method of self-reporting, can provide an estimate of the overall mode split for an entire population as well as overall volumes of cyclists on a given day or week. With this method, cyclists using any route (not just those targeted for a traffic count) and parking in any location will be accounted for. In addition, a survey offers the researcher an opportunity to ask respondents information about their origins, destinations, distance travels, sociodemographic attributes, attitudes, and motivations. However, because it is usually impossible to survey an entire population, surveys often rely on sampling, which introduces the potential for bias. They also rely on self-reporting of behavior, which may not be completely accurate.. METHODS USED I DAVIS This paper presents results from three different methods of data collections: police records on reported bike thefts; a bike rack count (with snapshots at three different times of day for all outdoor bike racks on the UC Davis campus); and a travel survey of a random sample of the population, used to produce projections of the total number of people bringing bikes and storing bikes on campus on a typical weekday as well as the number experiencing thefts. TRB Annual Meeting

4 Police Records The UC Davis Police Department maintains records of all reports of bicycle theft on campus. These only include bikes stolen from the UC Davis campus. At the time that the other data were collected, filing a report with the police required submitting a paper form to the UC Davis police department that included the bicycle s serial number and other pertinent information; they have since implemented a system of filing a report online in hopes of streamlining the reporting process.. Rack Count Two separate counts of bikes parked in on-campus outdoor bike racks in the fall of 0 and the spring of 0. In both sets of counts, data were collected for bikes parked during a mid-morning hour (-am) and a mid-afternoon hour (-pm), corresponding to times of day when many classes are in session. In the spring 0 count, an additional count was conducted at -am, to capture a night-time baseline. During the fall 0 counts, different parts of campus were counted on different days, with data collection staggered over September,, and and October. In the spring 0 counts, the entire campus was covered on the same day, at -am and -pm on June and at -am the next morning on June. The count covered the entire core area of the UC Davis campus, an area approximately square miles and including bike racks for approximately,00 bikes, including on-campus residential areas. To accomplish this, the area was partitioned into sections that a single person could cover within an hour. For the 0 count, the campus was partitioned into sections, but some of these were found to be too large (or to contain too many bicycles) for a single person to finish counting in an hour (with over,00 bicycles in one of the partitions). For the 0 count, the campus was divided into sections, with no more than about,000 bicycles per partition, which a single person could cover (usually on foot and bicycle) within the hour. The counters consisted of TAPS student employees and volunteers consisting of students, faculty, and staff affiliated with or friends of the Institute of Transportation Studies. The counters were instructed to count every bike parked in or in the vicinity of designated bike rack areas in their section of campus, counting any almost-complete bike carcases (such as a frame with missing wheels) as a full bike. This meant that the number of bikes counted might exceed the number of spaces in the racks, as many areas have a substantial volume of overflow bikes not parked in a rack. At the same time, the counters did not look for bikes that might be located in obscure areas away from formal bike parking and there was no count of bikes inside any buildings. The counters noted the total numbers of bikes in different areas of a paper map, and TAPS staff entered the data into Excel spreadsheets and tabulated totals.. Travel Survey The Transportation and Parking Services (TAPS) at UC Davis in cooperation with researchers at the Institute of Transportation Studies at UC Davis conduct a survey each fall of a random sample of students, faculty, and staff to determine mode split for campus commuting, vehicle occupancy, bike and vehicle parking statistics, and awareness of campus transportation programs, among other things. The most recent survey (and closest in time to the June 0 bike rack count) was conducted in October of 0. It was an online survey administered via invitation to a stratified random sample of approximately 0 percent of the entire campus population of 0,0 people. About,0 people completed the survey, for an overall response rate of about percent. The survey included questions regarding respondents travel to campus on each of seven days prior to their survey; their use of bikes on campus after commuting to campus; storage of bikes on campus overnight; and any experiences of bike theft in the past year. See for more details.. RESULTS. Calibrating the Survey Sample to the Population As a part of this study, we use results from a sample of respondents to the Survey to make projections about the entire population, and compare these to other population-level figures (such as police reports and rack counts). These comparisons are only meaningful to the extent that the Survey respondents are representative of the population as a whole, at least with respect to their use of bicycles. For this population, we assume that people are roughly similar to one another, on average, within the following TRB Annual Meeting

5 0 role groups: freshmen, sophomore, junior, senior, Master s student, PhD student, faculty, and staff. We then weight the responses by these role groups so that the proportion of respondents in each group reflects their proportion in the campus population. We have limited ways of further evaluating the extent that the survey respondents are representative of the campus population. One attribute we can verify is the portion of the sample that owns parking permits, which we find matches the portion in the overall population closely. In particular, about percent of Survey respondents reported having a monthly, quarter, or annual parking permit, a projected, people; TAPS records of permits issued during the time of the survey indicate,0 annual, multiyear, quarterly, or monthly permits issued as of November 0, about percent of the population. However, there are some differences in the portion of Survey respondents holding each type of permit. Although both the TAPS records and the Survey results indicate that about three-quarters of the permits issued are either C or A permits, those with C permits are somewhat under-represented in the survey data, with about. C permit holders for every A permit holder in the survey sample, compared to about. C permits for every A permit issued by TAPS. Since A permits are more expensive and enable closer parking, we might conclude that if anything these respondents have invested more in the option of driving to campus and may be less likely to bike, meaning estimates of numbers of cyclists and thefts based on the Survey may be lower than they otherwise might be.. umbers of Bikes on Campus: Survey Results versus Rack Counts From the Campus Travel Survey, we have an estimate of the total number of people with bikes on campus on an average weekday. In particular, for each of the seven days during a reference week, respondents were asked to recall and report (a) their primary means of transportation to campus, (b) whether they additionally used a bike to get around after arriving on campus, and (c) whether they stored a bike on campus overnight. We find that among those physically traveling to campus on an average weekday during the reference week (about percent of respondents), about percent biked as their primary means of transportation (see Figure ). An additional number of respondents used a bike after arriving on campus by other means and/or store a bike on campus. In total, we estimate that about percent of respondents have a bike on campus on an average weekday, a projected, people with bikes during the day. A breakdown of these is shown in Figure. In part because this includes the percent of the population who live on campus, a substantial share of respondents report storing a bike on campus overnight. In total, about percent of all respondents had a bike on campus overnight on an average weeknight, a projected, bikes (included in the daily total of,). About half of the overnight bikes on campus on an average weekday belong to people living on campus. Bike % Sample n =,0 Projected N =, Train % Bus % Walk or skate % Carpool or ride % Drive alone % Figure : Primary means of transportation on an average weekday among those physically traveling to campus (Source: 0- UC Davis Campus Travel Survey) TRB Annual Meeting

6 Sample n =,0 Projected N=, Brought for the day as secondary mode of travel % (, bikes) Stored on campus overnight by someone living off campus % (, bikes) Owned by someone living on campus % (, bikes) Used as a primary mode of travel from off campus % (, bikes) Figure : Breakdown of daily bikes on campus campus (Source: 0- UC Davis Campus Travel Survey) Comparing these projections to the numbers of bikes counted on bike racks, we find that the Survey s daytime total is substantially higher than the counts and that the Survey s overnight figure is substantially lower (see Table ). As for the daytime figures, the results from the two studies are not exactly comparable statistics, since the Survey is an estimate of those who had a bike on campus at any moment during the day, rather than the snapshot of bikes on campus at a particular hour, which ought to be substantially lower. By contrast, we might expect the nighttime figures from the two studies to be more comparable, because we do not expect bikes to move around much at night, and therefore the am snapshot could be compared to the number reporting leaving a bike overnight. Yet we find a discrepancy of about, more nighttime bikes in the June 0 rack count than the projected number owned by campus community members according to the fall 0 Campus Travel Survey. To the extent that the figures from the two surveys are comparable, this discrepancy may be interpreted as an estimate of the total number of abandoned bikes on campus at any given time:, bikes, or percent of the nighttime total and percent of the total capacity in on-campus bike racks. Table : Estimated number of bikes on the UC Davis Campus Total bikes on campus: Rack Count (Fall 0) Data source: Rack Count (Spring 0) Campus Travel Survey (Fall 0), projections Overnight n/a, (am), (left overnight, on an average weekday) During the day,0 (am), (am), (pm), (pm), (at any point during the day, on an average weekday) Total rack spaces, n/a n/a Total population, 0, 0,. Gross Movements of Bikes Results from the Campus Travel Survey suggest that of all the people reporting having a bike on campus on average weekday (a projected,), about percent left their bike idle on campus (, bikes) and the remaining percent (,0) rode it at some point during the day. While the Survey data alone provide no information on how many of these bikes are on campus and parked simultaneously, the Rack Count gives some indication of this. In particular, deducting the estimated TRB Annual Meeting

7 0 0 0 number of abandoned bikes from the 0 daytime Rack Counts, we estimate that there are a remaining, and, unabandoned bikes parked on campus at am and pm. If the total on campus on an average weekday is,, then we can conclude that at am, about 0 percent of the (unabandoned) bikes that would be on campus at all during the day are currently there and parked; at pm, about percent of the total unabandoned bikes are there and parked... Stolen bikes: Reported on the Survey versus Police Reports Filed In responding to the Campus Travel Survey, we find that about percent of all respondents report having had a bike stolen from campus at some point in the past (about percent of those who have ever brought a bike to campus) and about percent say they have experienced a theft in the last year (about percent of those who have had a bike on campus during that time). This represents a projected, bikes stolen in the last year. The Survey asked respondents if these thefts were reported to the campus police and only percent indicated they had reported it, a projected thefts with police reports in the last year. Comparing these figures to actual reports from campus police, we find that the Survey estimates are still much higher than the number of thefts in police records. In particular, actual records from Campus Police indicate 0 bike thefts reported during the corresponding period (November, 0 through October, 0), just percent of the projected total thefts and half the supposedly reported thefts, as estimated from the UC Davis Campus Travel Survey.. CO CLUSIO S A D RECOMME DATIO Combining results from several different types of measurement efforts provides a richer picture of bicycle volumes than any one method alone can provide. In particular, the Survey results indicate that percent bike to campus on an average weekday as their primary means of transportation to campus ( percent among those physically traveling), but that percent has a bike on campus for one reason or another, a projected, people with bikes a figure that matters for those managing bike facilities on campus but one that would not be captured by conducting counts of bike traffic. From the Survey we get a sense of some of the different ways bikes are used, with about percent used as a secondary circulator mode to get around campus during the day and about percent belonging to people who live on campus. In addition, the combined findings from the Survey and the Rack Count show us that about 0 to 0 percent of the non-idle, unabandoned daily bikes are in motion (and not parked) at pm and am, respectively. Finally, only the combined findings from the Survey and the Rack Count can produce an estimate of the total number of abandoned bikes on campus, which we pin at, bikes, or percent of the total overnight bikes, percent of the total daytime bikes, and percent of the overall rack capacity on campus. These findings suggest some different needs for bike parking facilities on campus, perhaps including facilities oriented to secure all-day storage, more secure long-term overnight storage, and perhaps less secure but more convenient (optimally located) short-term parking for those riding between destinations on campus during the day. In addition, knowing that almost a quarter of rack capacity is consumed by abandoned bikes offers some sense of how much there is to be gained by more aggressive abandoned-bike removal, and/or programs designed to prevent abandonment in the first place. These might include marketing campaigns or educational programs designed to inform those graduating about what they might do with their unwanted bike; to encourage new students and employees to purchase higher-quality bikes that are less likely to break down and be abandoned; and to offer more options for or awareness of bike-repair options. Finally, better security, either through enforcement or more secure facilities might also help curb bike abandonment in the future. Better understanding the decision process for what type of bike to ride on campus in Davis as well as the steps that result in bike abandonment would be useful for campus planners and potential areas for future research. Understanding the role of each of these on overall cycling levels is also important. In evaluating bike security, it is critical for Campus Police to know that perhaps just percent of thefts are actually reported. In reconciling the estimated number of Survey respondents who said they reported their theft and the actual police records ( versus ), UC Davis Bicycle Program Coordinator David Takemoto-Weerts and Police Lieutenant Matthew Carmichael suggested that many people think they have reported a theft when they have not actually filed an official report. Since the time of this study, they have implemented a new online reporting system may increase the TRB Annual Meeting

8 0 number filing reports in the future. Additional marketing campaigns encouraging people to report thefts may help bring these numbers into line with one another. Aside from accurate reporting, the suggestion that almost in cyclists has experienced a theft at some point and over in had one in the last year seems important information for evaluating Davis as a bicycle-friendly place. In particular, understanding the extent that the fear of theft may inhibit cycling on campus, either directly or indirectly through the use of low-quality bicycles, is an important question for future research with implications for how much the campus might be willing to invest in enhanced security. While some of the concerns described in this paper are unique to Davis, there are other cities that may have comparable volumes of cyclists seeking different types of parking, such as longer-term versus shorter-term parking, and using bikes as a circulator mode in combination with other modes or as a part of a multi-modal trip chain. Sharing the experiences about the provision of and methods for evaluating the use of different types of bike parking facilities would be useful for planners at Davis and elsewhere. This paper shares how using a mix of different types of measurements can be valuable in estimating the scope of phenomenon such as bike abandonment, the use of bikes as a secondary mode, and under-reporting of bike thefts. The particular findings from Davis regarding the extent of the bike theft and abandonment problem may serve as an example for what other cities (or campuses) might make moves to avoid as cycling becomes more mainstream in those places. REFERE CES. Takemoto-Weerts, David. A Bicycle Friendly Community: The Davis Model. Paper presented at Pro Bike/Pro Walk conference, Santa Barbara, CA, September. Available online: Buehler, Ted and Susan Handy. Fifty Years of Bicycle Policy in Davis, CA, presented at the 0th Annual Meeting of the Transportation Research Board, Washington, DC, 0. Available online: Alta Planning and Design, National Bicycle and Pedestrian Documentation Project: Automatic Count Technologies. June 0. Available online from: City of San Francisco. City of San Francisco 0 Bicycle Count Report. January. Available online: nt_report.pdf.. City of Portland. Portland Bicycle Count Report 0. December 0. Available online: Lovejoy, K. Results of the 0- Campus Travel Survey. Institute of Transportation Studies, University of California, Davis, Research Report UCD-ITS-RR--. July. Available online from: TRB Annual Meeting