Promoting The Pedestrian Safety In Cold, Snowy Regions In Winter: A Case Study Of Winter Walking Environment In Sapporo, Hokkaido

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1 Promoting The Pedestrian Safety In Cold, Snowy Regions In Winter: A Case Study Of Winter Walking Environment In Sapporo, Hokkaido Yoko Shintani*, Fumihiro Hara*, Tetsuo Akiyama** Abstract In Sapporo, one of the largest cities in the northern region of the world, the number of pedestrians carried by ambulance to the hospital in winter has been increased rapidly due to slip and fall accidents on the extremely icy slippery roads. For residents, especially for the elderly and disabled, walking under such conditions entails greater risk of serious injury; therefore, they are discouraged from going out during the long winter. On the other hand, it is said that pedestrians nowadays are wearing shoes and apparel less suitable for conditions of cold and snow, in response to the physical improvements; over the past few decades, the City of Sapporo has made urban infrastructure more resistant to cold and snow. In light of this, the city would exhaust its resources if it were obliged to eradicate snow and ice from the city so that people could enjoy a snow-andice-free environment like that in summer. In order to meet the needs of residents without excessive physical improvements, and to develop the alternative measures taken by not only the city but also any group or individual to prevent slip and fall accidents in winter through their own efforts, it is essential to understand the nature of extremely icy slippery roads and where slip and fall accidents often take place. Considering the above, surveys on pedestrian falling accidents were conducted in downtown Sapporo. The surveys identified physical characteristics of locations where slip and falling accidents often took place. It was revealed that changes in the microclimate have significant influence on the friction coefficient of the walkway surface. Based on the survey results, this paper discusses alternative measures to diminish the risk of slip and fall accidents without heavily depending on the conventional snow- and ice-control measures. Contact details *Hokkaido Development Engineering Center #11, South-1, East-, Chuo-ku, Sapporo, Hokkaido, Japan , **Tokyo Metropolitan University 1-1 Minamiohsawa, Hachiohji-shi, Tokyo, Japan,

2 Promoting The Pedestrian Safety In Cold, Snowy Regions In Winter: A Case Study Of Winter Walking Environment In Sapporo, Hokkaido Yoko Shintani, Fumihiro Hara, Tetsuo Akiyama Introduction With the emerging needs of a Òbarrier-freeÓ environment as the proportion of elderly to the general population increases rapidly, the improvement of the environment for winter pedestrians has become one of the major issues of road management policies in Sapporo, Japan. In particular, icy slippery walkway surfaces increase the likelihood of accidents whereby pedestrians slip and fall (hereinafter, Òfalling accidentsó). Such a walking environment raises the likelihood of accidents for people whose mobility is not otherwise diminished. For the elderly, whose mobility is often diminished, such a walking environment makes conditions more than just uncomfortable: It is a major impediment to their mobility during winter. Although the development of snow and ice control measures such as extensive snow removal operations, road maintenance, and urban infrastructures resistant to winter climate has placed a great emphasis on the improvement of pedestrian walkways, the existing measures for the improvement of winter pedestrian mobility are not effective enough to reduce falling accidents. Moreover, a lot of attention and many resources have been devoted to the extension of the amount of snow removal or de-icing on the streets, as urban sprawl and auto-oriented lifestyles become apparent, yet the demand for more and higher quality snow clearance services has never been satisfied. For example, residents in Sapporo have ranked improvement of snow-removable services as the highest request since This paper discusses issues on winter pedestrian safety in downtown Sapporo, one of the largest urbanized areas in the northern region of the world. A falling accident survey and a walking environment survey were conducted to analyze pedestrian behaviours and causes of falling accidents in winter. Based on the survey results, this paper discusses alternative measures to diminish the risk of slip and fall accidents without depending on the conventional snow- and icecontrol measures. Pedestrian And Winter Walking Environment The City of Sapporo banned studded tires in 1991, to eradicate pollution of the dust abraded by them. However, this led to a rapid increase in slippery surfaces, which deteriorated the winter walking environment. Figure 1 summarizes changes in the number of fallers carried by ambulance in winter and the studded tire equipping rate in Sapporo. The figure indicates that approximately 00 accidents occurred every year in the second half of the 1980s, when studded tires were still being used. Since 199, however, when the transition to studless tires was complete, the yearly number of accidents has increased dramatically to Although no scientific studies have confirmed a connection between the discontinued use of studded tire and the increase in slippery icy sidewalks and pedestrian crossings, the correlation between those two incidents is widely suspected.

3 Falling accidetns Studded t ire equipping r (? Number of accidents St udded tires were banned in the Cit y of Not.4 availabl Source: Fallers is based on the total number between December and February of the relevant fiscal years, derived from ambulance rescue records of Sapporo Fire Bureau, City of Sapporo. The equipping rate is based on surveys by the City of Sapporo for the coldest period of winter. Figure 1. Changes in fallers carried by ambulance in winter and the studded tire equipping rate in Sapporo Pedestrian And Snow And Ice Control Measures Although the increase in accidents due to pedestrians slipping and falling indicates the severity of walking conditions in winter, it is fallacious to say that no measures have been taken by the city government to improve pedestrian safety in the winter. Urban infrastructure has been improved to be more resistant to snow and cold in downtown Sapporo. Figure and show the transition between 1968 and 000 of locations of the improvements, including road-heating systems on sidewalks, covered passageways such as arcades, colonnades, skyways, underground shopping malls and walkways, and the subway system. As of 1968, only part of the Tanuki-koji arcade existed, road-heating systems were installed on only four sidewalk blocks between Odori and Sapporo Station, and the subway system was not in place. In the past thirty-two years, road-heating systems on the sidewalk, covered passageways, and underground facilities have been extended enormously to achieve a snow-free environment in downtown Sapporo. In addition, the budget for snow removal has been increased rather dramatically in the past fifty years. The snow removal budget in 000 finally exceeded 10 billion yen, and over 9% of city roads and sidewalks had snow removed on a regular basis (Shinmori et al. 00).

4 Figure. Road heating and covered passageways in downtown Sapporo [1968] (Shinmori et al. 00) Figure. Improvements of urban infrastructures in downtown Sapporo (000) ] (Shinmori et al. 00) Problems With Existing Walking Environment: WhatÕs Wrong? Clearly, much attention and many resources have been devoted to the expansion of snow and ice control measures, as urbanization and auto-oriented lifestyles increase in Sapporo. Nevertheless

5 the demand for more snow and ice clearance services has never been satisfied. According to the annual public questionnaire survey conducted by the city, residents in Sapporo have ranked the improvement of snow removal services as the top request since 1978; among this request, the demand of snow and ice control measures for community roads and residential streets has been placed as a primary concern (City of Sapporo 00). Shinmori et al. (00) suggests that such a contradiction is Òa dilemma between the limited resources available for public services and the limitless personal desire for a more comfortable urban environment.ó In their study, they found that the amount of pedestriansõ winter clothing has decreased over time, concurrent with the extension of snow and ice control measures and the improvement of urban infrastructures. In this context, there is no doubt that the city would go into bankruptcy if the public service were to totally eradicate snow and ice from the city limits in order to create a Òsnow-and-cold-freeÓ environment like that in the summer. On the other hand, accidents of pedestrians who slip or fall seem to be steadily increasing each year. This type of walking environment paralyzes the mobility of the elderly or physically disabled. It also discourages them to go out during the long winter, which may lead to a lack of daily exercise necessary for a healthy lifestyle. Suda et al. (1997) conducted a questionnaire type survey of men and women over the age of 6 who reside in Sapporo in order to compare the frequency of daily exercise between snowy seasons and seasons without any snow. The survey revealed that the ratio of men and women who do exercise regularly decreases significantly in snowy seasons. Especially, the ratio of women who do exercise regularly showed a sharp drop; only 8% of women do exercise more than three times a week in snowy seasons, whereas % in seasons without any snow. In order to resolve those complicated issues raised above, it is essential to examine various factors suspected of contributing to falling accidents. Two types of falling accident surveys were then conducted to analyze pedestrian behaviours and causes of falling accidents in winter. Falling Acceident Survey It is very difficult to count every single person who fell or nearly fell in downtown Sapporo and to record the scene and location of every such accident. The locations most prone to falling accidents were identified in order to survey specifics of the walking environment and falling accidents there. For the identification, the number of ambulance rescues for falling accidents in the winters (December to March) of fiscal 1996 through 1999 was sorted on a block-by-block basis (Table 1), because streets run parallel north-south and east-west to form a neat grid in the city center. It is interesting to note the high distribution of falling accidents at South 4 t, which is in the Susukino nightlife district (data exclude the number of fallers sent to the emergency room that operates during the Sapporo Snow Festival held in early February). Since most accidents occurred at night (17:00-6:9), causes are assumed to be not merely icy surfaces and snowfall, but also intoxication of pedestrians. In contrast, falling accidents during daytime (7:00-16:9) are highly distributed at South t and, where retails shops, restaurants, and similar business establishments concentrate. A high distribution between 14:00 and 17:00 indicates that most injured fallers are shoppers. Among the 11 fallers at those blocks, 7 were women aged 8 or over. This trend agrees with the conclusion of Hara et al. (1999) that Òthe number of falling pedestrians increases in proportion to age, and accidents are especially numerous for women in their 0's or over.ó Table 1. Block-by-block number of ambulance rescues for winter fallers

6 N g 1996?` 1999?@?iDecember-March?j 199 6?` 1999?@?iDecember-March?j Daytime?i7:00? `16:9?j Nighttime?i17:00?` 6:9?j t Eas East Eas Eas 1 Eas Eas North North 8 North 8 North North North 7 North North North North 6 North 6 1 North North North North North North 4 1 North 4 North North North North North North North North North North North North 1 North North Odori 6* Odori Odori 4 * 4 9 Odor South South 1 South South South South South South South South South 1 South South South 4 South South South 1 South South South South South 6 South South South South 7 South South South South 8 South South South South 9 South South Sout h South 10 South Sou t h t Eas 1 1 East Eas Eas 1 1? Odori-6?F A medical emergency r oom was temporalily placed here for t he? Odori-6?F A medical emergency room was t emporalily placed here f or t Source: Report on Falling Accidents due to Snow, by the Rescue Section, Fire Prevention and Control Department, Sapporo Fire Bureau Survey On Falling Accidents By Video Camera To accurately reveal the characteristics of pedestrians who fell or nearly fell, we videotaped the locations of falling accidents and near-falling accidents, the conditions of those locations, and the scenes of such accidents, in the survey area (South 1 and, t ). These locations were selected according to the results of the aforementioned falling accident survey. Video cameras were installed on the second floor of commercial buildings at the intersection for a bird's-eye view of one spot each of the east-west and north-south pedestrian crossings, for sex and age recognition from appearance of pedestrians. The recording time of day was the to hours between around 1:0 and 17:00, to 4 times a week from January 9 to February 17, 001. The total recording time and days are 1 hours 16 minutes and 0 days. Falls and near falls numbered 1 in the survey period, of which 4 (16%) were falls. Most falling accident locations were steep transitions from sidewalk to ice-covered pedestrian crossing. On January 7, the day on which the number of falling accidents was the greatest in the recording period, the occurrence of falling accidents concentrated at level sections of pedestrian crossings covered with black ice. Also, pedestrians tended to fall or almost fall in succession at the same place (Figure ). Eas Eas S1W?kLocation 1?l Rgd N O?D Date Time : : : : : : Department Store 1?C ?C11?C1 14?` 6?C ?C9 Location Location 1 Rgd SW?kLocation?l N O?D Date Time Rgd : : : : : : : : : : :0 NO?D Date Time : : : : : : : : : : :

7 Figure 4. Locations of falling accidents in the survey area Photo 1. Slip and Fall Accident: January 14, 001 Table compares the number of pedestrians and that of people who fell or nearly fell at fallingprone locations. The table shows that people who fell or nearly fell account for approximately % of all pedestrians. The table also demonstrates that although male pedestrians were fewer than female ones, the number of males who fell or nearly fell was greater than that of females. The age was determined by the surveyors according to appearance. Although it is difficult to confirm the accuracy of the results, they show that falling or near-falling accidents numbered largest for people aged 16-0, who go out more than any other age group. Table. Number of fallers and near-fallers by sex and age (Jan. 7) Female Male Total No incident % Slipped and /or fell % Total % Infant Child Teens- 40's-60's 70's 0's Total No incident % Slipped and/ or fe % Total % Conclusions As a result of the surveys above, the following conclusions were reached. ÅE Falling accidents frequently occur at night in the entertainment district during winter. It is not only the icy surface and snowfall that are responsible for accidents, but so is the intoxication of pedestrians. ÅE Falling accidents often take place during daytime in districts where commercial establishments concentrate. Shopping districts are considered to account for a major share of pedestrian falls. ÅE Many falling accidents occur at the transition between pedestrian crossing and ice-covered sidewalk, as well as on black-ice-covered pedestrian crossings. Also, pedestrians tended to fall or almost fall in succession almost exactly at the same place. ÅE Risk by age is not clearly reflected in the result of survey on falling accident by video camera since no alternative method was available to confirm age distribution of all surveyed pedestrians besides the surveyorsõ speculative judgement. ÅE The survey results concerning the risk by sex suggest that likelihood of falling accident is greater for men than for women, which does not agree with Merrild et al. (198), Hara et al. (1990), and Hara et al. (1999). A possible reason is that those studies did not always limit their focus to seriously injured fallers. Therefore, although the risk of falling is higher for men, it is fair to say that women fallers are more likely to suffer serious injury. In view of these results, the following proposals are made to promote safer walking environment in downtown Sapporo in winter.

8 ÅE The video survey results confirmed that many falling accidents occur on transition areas between the sidewalk and the pedestrian crossing at intersections. In many of such areas, the slopes are steep and uneven, and a high degree of steepness results from differences in the level of snow removal on the sidewalk and the pedestrian crossing. A possible countermeasure is to change the intersection structure to remove uneven spots on the surface. If structural change is not feasible due to land use restrictions, installation of snow-melting facilities, such as road heating, needs to be examined. ÅE Falling also takes place frequently on black-ice-covered surfaces of the pedestrian crossing. Even when the level of snow removal is higher than that of the sidewalk and measures are taken for the surface, pedestrians often fall at spots with low coefficients of friction. In such cases, extensive road surface management of carriageways (application of anti-freezing agents) is most important. However, snow-melting facilities, freezing-prevention pavement, or other measures must be studied for pedestrian crossings where slippery road surfaces frequently form by large traffic volume and shade of buildings. ÅE The risk is higher for men than for women, but the likelihood of serious injury is higher for women. It is therefore necessary to take measures to prevent all types of pedestrians from falling. However, municipalities in cold, snowy regions devote a large portion of their budgets to winter road surface management, so budgets are limited for facility- and equipment-based measures to improve the walking environment. Selection and implementation of such measures must therefore address all relevant aspects, such as land use, pedestrian volume, the number of traffic accidents, and construction, maintenance, and management costs. Improvement of non-equipment and non-facility aspects also is imperative. For example, pedestrians themselves should take measures to prevent falling by changing their way of walking and transportation means depending on their physical ability. References City of Sapporo. n.d., Snow Control Measures in Sapporo (online) [Accessed 4 July 00]. Fire Bureau, City of Sapporo. n.d., Fallers is based on the total number between December and February of the relevant fiscal years, derived from ambulance rescue records of Sapporo Fire Bureau, City of Sapporo. The usage rate is based on surveys by the City of Sapporo for the coldest period of winter. Hara.F,Kawabata.K,Kobayashi.H Study of Pedestrian Injuries in Winter in Sapporo, 6th Cold Region Technology Conference '90, CTC900407, pp Hara, Akitaya, Suda, et al Survey on WomenÕs Awareness of Walking in Winter,Å@Research on Enhancement of Safety of Winter Life in the Cold, Snowy Regions, pp.1-6. Merrild,U. and Bak,S An Excess of Pedestrian Injuries in Ice Conditions: A High-Risk Fracture Group_Elderly Women, Accident Analysis & Prevention, Vol.1.No.1, pp Shinmori, Konno, Saga, and Hara. 00. Interrelations between Lighter Winter Clothing of Pedestrians and the Development of Urban Anti-Snow and ÐCold Measures. In Proceedings of Winter Cities Forum, Winter Cities 00 Aomori. International Association of Mayors of Northern Cities, Aomori City, February 7-10, pp.7-4. Suda, T., Moriya, T., & Nakagawa, K, Lifestyle and Activity of the Elderly in Cold, Snowy Regions. Hokkaido University Publication. Sapporo, Japan.