3.1. Transport Mode Choices
In 2010, the majority of students chose walking for commuting to the BCTF, 46%, while 38% used cars, both their own (30%) and shared (8%;
Figure 2). The choice of other active modes of transport was lower: 8% travelled by bicycle and 7% by PPT. For staff, the modal split and origin of commute trips differed from those of students (
Figure 2,
Table 1). The predominant transport mode choice was car, used by 64%, of which 56% used their own car and 8% used a shared car. When choosing active modes of transport, 24% opted for waking (the second most common modality), 7% for bicycling, and 5% for PPT. Thus, staff used cars practically once more and walked half as often as students, while the use of other modes (bicycling and PPT) was similar in both groups. The large discrepancy in the proportion of car users between students and staff is likely the result of the availability of cheap employer parking for staff (
Section 2.1).
The most significant change in student commuting in 2020 compared with 2010 was the 22% decrease in car use (own and shared;
Figure 2). The change was reflected in a 9% increase in walking and a 13% increase in the use of PPT. The observed modal shift could be the direct result of the reduction in the number of free public parking places in the city center, the increase in parking fees, and the extension of the pedestrian zone in conjunction with the introduction of integrated PPT tickets at the national level (
Section 2.3). The proportion of active commuting and car use (own and shared) by staff in 2020 was similar to that in 2010, but the relationships between the modes of the two groups were different—the use of bicycles, PPT, and shared cars increased (
Figure 2).
The comparative results of the two surveys were very encouraging, as the distribution of trip origins by subzones of the study site had remained practically unchanged over ten years (
Section 2.2,
Table 1). This led to a detailed study of the modal split by four zones (
Figure 3 and
Figure 4).
Looking at the results for the combination of zones 1 and 2 (
Figure 3a), we find that students within 2 km of the BCTF preferred to walk during the investigated period (74–77%), while bicycling was not as popular (12–11%). The low proportion of bicycle use related to the short distances and a scant bicycling tradition, which was repeatedly confirmed in conversations with students in our lectures. However, the proportion of car use on these short distances was 14% (own and shared) in 2010 and has decreased to 5% by 2020. This change was reflected in a 4% increase in walking and a 6% increase in the use of PTT. Walking was also the preferred transport mode for staff during the investigated period (46–39%), but they used it 1.8 times less frequently than students. For distances up to 2 km, which can be easily covered on foot or by bicycle, they used cars (own and shared) by 40–27%, which, as mentioned in the first paragraph, can be attributed to the employer’s parking policy. Over a ten-year period, the largest shift in staff commuting has involved bicycling and car use. The former has increased by 17%, and the latter has decreased by 13%.
The more detailed transport mode structure of students and staff at the BCTF in 2020 in zones 1 and 2 can be discussed with the help of
Figure 4. It is noteworthy that still up to 3% of students used a car within 1 km, that the proportion of walking and bicycling decreased with distance by 19% and 3%, respectively, and that the use of the city PPT became interesting among students at distances between 1 and 2 km (16%). The high percentage of active commuters among students decreased rapidly with increasing distance from the trip origins, which can be explained in part by the fact that the bicycle and pedestrian system was the best in the city center and deteriorated rapidly with increasing distance (
Section 2.1 and
Section 2.3). Staff also predominantly chose active commuting within 1 km of the BCTF, though 20% of them used cars, which is 1.7 times more than a typical household in Maribor [
43]. Within 1–2 km of the BCTF, staff interest in bicycling remained the same, but car use increased to 35% and became the predominant transport mode. This is the direct result of the availability of very cheap parking near the BCTF, which is also true for other subzones of the study site.
Figure 3b illustrates the transport mode structure of students and staff within a radius of more than 2 km of the BCTF. Only 15% of students commuted by PPT in 2010 and as many as 72% by car (own 58% and shared 14%). The results indicate, on the one hand, that the city PPT was unattractive and, on the other hand, that PPT from the suburbs was insufficient. The situation had changed by 2020, when PPT was the predominant transport mode among students (49%), and car use decreased to 41%. The proportion of car use and active transport among staff has not changed over a decade-long period, which is not the case for the relation between the modes of the two groups, i.e., the proportion of the use of shared cars and bicycles has increased by 7% and 5%, respectively.
The details of the commuting structure in zones 3 and 4 of the study sites in 2020 are presented in
Figure 4. PPT was the predominant transport mode (49%) for the minority of students accommodated within 2 and 5 km of the BCTF (6%), while 20% of the staff living in this zone (
Table 1b) travelled by car (69%; 52% by their own and 16% by a shared car) and 15% by PPT. As distance increases, the MOM’s measures to encourage the use of PPT become noticeable, namely subsidising PPT tickets in conjunction with parking restrictions near the BCTF. The proportion of students commuting to the BCTF from zone 4 and using PPT remained the same, but car use increased to 47% (own car to 34% and shared car to 13%). Cars were the primary transport mode for 89% of staff, 16% of whom shared a car. The use of PPT decreased to only 5% within distances over 5 km of the BCTF, as these commuters could not use the city PPT, but mainly the regional PTT, which operated at a much lower frequency and was therefore less suitable for daily commuting. This was not true for students, as their financial situation was different, which affected their commute modes and places of residence. On the one hand, many of them did not own a car, and on the other hand, they had the opportunity to buy cheap integrated tickets (
Section 2.3). The proportion of shared cars has not changed significantly for a decade.
The largest changes in student modal split from 2010 to 2020 occurred in zones 3 and 4 of the study site, especially for distances greater that 5 km to the BCTF, from where 34% of students commuted—car use decreased by 30% (own car by 28%) and the use of PTT increased by 34% (
Figure 3b and
Figure 4). The results suggest that students have been very receptive to the subsidized regional PPT tickets and considered them a better option than using a car every day or accommodating close to the BCTF.
The largest changes in staff modal split between 2010 to 2020 occurred in zones 1 and 2, which accounted for 44% of trips—as mentioned earlier, car use decreased by 13% and bicycle use increased by 17% (
Figure 3a). Only in zones 1 and 2 were they more likely to ride a bicycle than students. However, car use within 1 km of the BCTF increased from 20% to 35% within 1 to 2 km in 2020. Again, the explanation for this is the availability of very cheap parking places provided by the employer. In all four zones of the study site, staff were less likely than students to commute by active transport. They were not interested in using regional PPT for distances greater than 5 km to the BCTF, from where 48% of them (the majority) commuted, while this mode of transport was of interest to as many as 49% of students. At this distance from the BCTF, the percentage of staff and students sharing a car increased to 16% and 13%, respectively.
The findings are consistent with the studies of Delmelle and Delmelle [
14] and Hidalgo-Gonzalez et al. [
52], who reported that distance from the university is a major determinant of mode choice and that walking is the primary mode of transport for students living within 2.5 km of the campus, while cars become more popular beyond this distance. Our study also indicated that students were much more receptive to price-based interventions. The unavailability of free parking, the increase in parking fees, the subsidization of PPT, and the introduction of the integrated PTT ticket convinced many to use PPT instead of cars for longer distances and to walk or bike for shorter distances. Modal shifts were much smaller for staff. The main reason that the implemented measures did not have the same impact on staff is that most staff could park their cars in reserved lots near the BCTF almost for free (
Section 2.1), and they have a different financial status.
Regarding staff gender (
Figure 4), differences were negligible for distances up to 2 km to the BCTF, with the exception that female staff within 1–2 km were more likely to use the city PTT instead of walking. The same was true for student genders, except that male students were more likely to use bicycles and cars for distances up to 2 km. These results are consistent with the findings of the national cross-sectional study by Jurak et al. [
53], which involved Slovenian schoolchildren aged 12 to 15 years. They revealed a somewhat different picture than most previous studies, which found that active commuting to school was more common among boys than girls. They show that the difference in active commuting between genders is negligible, but more girls than boys walk to school, while more boys than girls use so-called wheel commuting to school (by bicycle, skateboard, roller-skates or kick scooters). The similarity with our results highlights the transfer of habits to university and the importance of raising awareness of sustainable mobility in the early stages of education.
It is interesting to note in
Figure 4 that male staff and male students used PPT (the city PPT) more frequently than their mates only for distances between 2 and 5 km to the BCTF, and only in this zone did female students use bicycles more frequently than male students. Male students were more likely to use their own cars than female students in all zones of the study site (3% to 16%), which represented the largest difference according to the two genders. Up to distances of 2 km from the BCTF, the proportion of staff commuting by personal car was similar for both genders. However, at distances of 2 to 5 km, and at distances greater than 5 km, female staff were about 10% more likely to use their own car than male staff. On the other hand, male staff and male students were twice as likely as female staff and female students to share a car for longer trips. The results suggest that female students and female staff are more likely to share a car than their mates only for distances up to 2 km from the BCTF. This might be related with Slovenian tradition, as explained by Jurak et al. [
53]. For distances up to 2 km from the BCTF (which was typical for the mentioned study), female students and female staff were used to share a car with known persons (relatives or friends). For longer distances, the situation is different, especially for distances outside the city (more than 5 km), where a car is often shared with unknown persons. At these distances, male students and male staff felt safer sharing a car.
3.2. Reasons for Car Use
Staff emphasized comfort and time predictability (28%), speed (24%), and combining transport with other activities (15%) as the most important reasons for choosing a car to commute to the BCTF (
Table 2), which is closely related to convenient and cheap reserved parking. Reasons for car use did not differ by more than 3% between staff genders, except for combining transport to the BCTF with other activities, which was more important for female staff by 7% (they were likely to have more family errands to run). Students also reported comfort, time predictability, and speed as the main reasons for commuting by car, but in reverse order to staff. In contrast to staff, sharing a car with relatives, classmates, and acquaintances ranked third (15%), and combining the trip to the BCTF with other activities ranked fourth (13%). Reasons for car use did not differ by more than 4% between genders.
In total, 8–9% of students and staff had no other alternatives to cars for commuting to the BCTF (
Table 2). The largest difference in reasons for car use between staff and students, 7%, involved a shared car and parking availability—the latter was more important for students who depend on public parking, while the former was less important for staff.
Previous studies have reported that institutional parking policies have a large impact on commuting by own and shared car (
Section 1). The high percentage of staff commuting to the BCTF by car can be explained by the fact that 86% of the staff have the parking option in the facility’s lots (
Section 2.1,
Figure 3,
Table 3a). The majority of students parked in free and paid public street parking lots near the BCTF, 85%, while 7 to 10% of them parked in free parking lots in nearby shopping centers. Consequently, 98% of the staff did not take time to find a parking place, or the time was shorter than 5 min. In contrast, 86% of students took up to 10 min to find public parking, and 11% took between 10 and 15 min. The previous study evidenced that finding a parking place accounts for 11% of traffic in the city of Maribor [
54]. Nevertheless, 57% of students took less than 5 min.
The main barriers for staff to share cars to get to work (
Table 4) were time adjustment (32%) and inappropriate or too short distances (23%). Lack of information about shared cars, coordination of drop-off points, and lack of confidence in the accuracy of arrangements (delays and trip cancellations) hindered them by 12–14%. Time adjustment (20%) and inappropriate distances (28%) were also the main barriers for students to share cars for commuting. As expected, the former was 12% less important for young people than for staff. Only the proportion of barriers to personal safety differed slightly more from that of staff—it was 8% higher for students, suggesting that students were more likely to share a car with unknown people than staff. Most student gender responses differed up to 3%, except two. Inappropriate distances were an 11% more important barrier for female students and a 6% lack of information about shared cars for male students.
A total of 25% of the staff indicated that no action would change their habits of choosing carpooling or car-sharing more often to commute to the BCTF (
Table 5), and 21% indicated that assistance in finding carpoolers would be effective. Most responses from two genders differed by up to 3%, except two. Assistance in finding carpoolers and raising awareness of the benefits of sharing a car were more important and less important, respectively, by 5% for female staff. Students highlighted the same two interventions as staff, but reserved parking would be the most important measure to increase the use of shared cars among students (12–26% more than among staff), because only public parking lots are available to students. Responds of the genders differed by only up to 3%.
3.3. Barriers and Interventions to Stimulate Active Commuting to the BCTF
Inappropriate or too long distances and poor infrastructure were the main barriers to bicycling to the BCTF for 29% and 20% of staff, respectively (
Table 4). Hygiene reasons (lack of showers and changing rooms) and accident risks (conflicts between bicyclists and pedestrians and between bicyclists and cars) hindered 16% and 12% of staff, respectively. Gender responses differed by only up to 3%.
Students had different views on the barriers to commuting by bicycle than staff (
Table 4). They also emphasized inappropriate distances (12% less than staff), but lack of bicycle ownership, dislike of bicycling, and risk of bicycle theft were also important barriers for 23%, 18%, and 16% of students, respectively. The reasons are related to their origin of trips. On the one hand, 42% of trips originated from zone 1, where students preferred to walk (
Table 1,
Figure 3a), which could be interpreted as an inappropriate distance and dislike of bicycling. On the other hand, 34% of trips were from zone 4, which could be related to inappropriate distance, lack of bicycle ownership, and risk of bicycle theft, as safe bicycle storage is rarely available in dormitories and private housing. These responses provided another explanation for why bicycle use among students did not change between 2010 and 2020 (
Section 3.1). In terms of genders, 5% more female students than their peers did not own a bicycle, and 4% more female students than their peers did not like to ride a bicycle. This is consistent with previous findings. Consequently, poor infrastructure was a greater barrier for 6% of male students than for their peers.
The vast majority of staff (35%) indicated that no action would cause them to bike more (
Table 5). They also indicated that changes in priorities at intersections (bicycling pockets and longer green phases), integration with PPT (bicycle parking lots and rentals), and subsidies for e-bike purchases would be effective interventions for 17%, 14%, and 12% of staff, respectively. In total, 6% more female than male staff reported that no action would increase their bicycling, and 9% more male staff indicated that subsidies for the purchase of e-bikes could increase their interest in bicycling. Students emphasized the same interventions to increase bicycling as staff but in different proportions. In addition, 18% of students (10% more than staff) pointed to bike sharing. Gender responses differed by only up to 3%.
Inappropriate distances were the main barrier to walking to the BCTF for 60% of the staff (
Table 4), which can be explained by the fact that 69% of the staff commuted from zones 3 and 4 (
Table 1). A total of 17% of the staff preferred other transport modes. Gender responses differed by only up to 2%. With 29% fewer students than staff commuting from zones 3 and 4 (
Table 1), inappropriate distances were the main barrier to walking to the BCTF for 48% of students. On the other hand, 13% more students than staff preferred other transport modes, which can be explained by the decrease in walking in zone 2, from which 18% of students commuted (
Table 1,
Figure 3a). Gender responses differed by no more than 5%. Inappropriate distances were more important for female students and accident risks for male students. This demonstrates that female students shifted walking and PPT (
Section 3.1).
As many as 52% of the staff believed that no intervention could persuade them to walk more (
Table 5), which is related to the origin of their trips (
Section 3.1). In total, 19% of them would be encouraged by greener pedestrian infrastructure and 15% by safer pedestrian infrastructure (e.g., crosswalks, wider pedestrian zones, and sidewalks). A total of 7% more female than male staff felt that no intervention could encourage them to walk more. The same interventions to encourage walking were also important to students. However, 18% fewer students felt that no intervention could persuade them to walk. Like female staff, 8% more female students than their peers felt that no measures could persuade them to walk more.
Lack of PPT connections and low frequency of trips were the main barriers to commuting to the BCTF by PPT for 26% and 25% of staff, respectively (
Table 4), which was reflected in the very low use of the city PPT from zone 3, and especially the regional PPT from zone 4 (
Section 3.1). Too distant bus stations, a dislike of PPT as a transport mode, and too short distances were barriers that hindered 13–19% of staff. Gender responses did not differ by more than 5%. Student responses differed slightly from staff. Since the majority of students commuted from zones 1 and 2, too short distances were emphasized by 37% of students (24% more than staff). Too distant bus stations and a dislike of PPT hindered a similar proportion of students and staff, while the lack of PPT connections and frequency of trips were less important to 11–13% of students. The low frequency of trips and a dislike of PPT were more important barriers for 6% of male students and too short distances for 9% of female students.
Faster travel (e.g., fewer stops and reserved yellow lanes) was the intervention that would encourage the most staff (24%) to use PPT more often (
Table 5). Better accessibility and synchronization of PPT (e.g., transfer points and schedule) would persuade 16–17% of staff, and better ticketing (integrated tickets and subsidies) and fewer delays 11–13% of staff. Students had similar views on interventions to increase the use of PPT. Their responses did not differ by more than 6%, with fewer delays being more important to students. The gender responses of staff and students did not differ by more than 3%.
3.4. Guidelines for the TDM Strategy at BCTF
The differences in travel behavior between the BCTF students and staff during 2010–2020 were merely the result of transport policies implemented at the municipality level (
Section 3.1). It is pointed out, on the one hand, that students are much more receptive to monetary-based policies and, on the other hand, that it is extremely difficult to achieve significant modal shifts among staff until they can use cheap reserved parking places near the BCTF. The results confirm the previous findings [
2,
30,
32,
34,
41] that a combination of subsidizing bus use, unavailability of free parking, and monetary parking fees are effective modal shift measures, and that students are willing to use more sustainable modes of transport if they live close to the faculty. Although the differences in travel behavior between genders were less significant, some of them should not be ignored in planning.
Since we analyzed the data by distance, we cannot only find the most appropriate measures for specific user groups, but also determine where they can best be implemented (geographically). The detailed analysis of responses to the questionnaires on the barriers to the use of the chosen transport mode and on interventions to increase the use of this mode also give us a powerful tool to find the most effective measures to design TDM. It is also worth highlighting that 8–9% of students and staff had no alternatives other than using a car to get to the BCTF.
In addition to our research, we also considered the latest findings on the key elements of sustainable urban mobility plans in Slovenian towns [
55] and the impact of changes in PPT tariffs on travel behavior [
56].
Table 6 summarizes the proposed interventions for the TDM strategy at the BCTF that focus on reducing car use for daily trips. The interventions should be evaluated based on the difficulty of implementation and potential outcomes, and the proposal should be linked to city-level actions, as the BCTF and other UM faculties are distributed throughout the city and share infrastructure and services with other users.