Journal articles on the topic 'Roads – Snow and ice control – Ontario'

In Japan, the regulation of studded tires requires the establishment of new countermeasures for effective ice control on slippery roads in winter. The most important information for snow and ice control systems is determining the slipperiness of road surfaces. To detect the slipperiness simply and precisely, a monitoring system was examined in which drivers judged the slipperiness. To evaluate the suitability of such slipperiness data, three investigations were carried out: (a) the relationship between the road condition classification and the slipperiness index, (b) the effectiveness of the subdivision of road classification, and (c) the comparison of slipperiness indexes with the actual friction coefficients. To address the first problem, the road conditions were investigated for 1 month with the cooperation of 10 taxi companies. It was found that the subjective slipperiness index was more sensitive to changes in weather conditions than the road classifications, and that icy roads do not always correspond to slippery roads. That is, there was a limitation on expressing road conditions by road classification. For the second problem, a similar investigation was performed by subdividing the road conditions into more classes. It was concluded that the subdivision of road classification is not so effective in precisely representing the slipperiness of roads. For the third problem, it was clarified that the subjective slipperiness indexes more or less agree with the actual friction coefficients. As for the results, the slipperiness index showed potential for use in snow and ice control systems.

The paper assessed the phytotoxicity of the most frequently used ice-melter reagents in Moscow (sand and salt mixture, anti-freeze reagent based on a composition of calcium and sodium chloride, technical salt), snow with varying degrees of contamination of the remnants of ice-melter reagents, as well as soil after the snow cover melting. The toxicity assessment was carried out in the samples taken on the lawns along the roads in nine administrative districts of the city in places with the same anthropogenic load. The test object is oat seeds (Avena sativa), as a sensitive biotest showing the most stable and reproducible data compared to seeds from other crops. Salt solutions of reagents with dilution rates of 1, 2, 4, 6, 8 and 10, melted snow and soil extracts were used for biotesting. The phytotoxic effect was determined by comparing the average root length of control and prototype seeds. It was found that all studied ice-melter reagents have a pronounced toxic effect on oat plants even at tenfold dilution. The phytotoxic effect of snow and soil polluted with ice-melter substances, which in turn inherits the chemical composition of snow cover after its melting, was shown.

The growth of winter travel on alpine roads in the western United States has increased the risk to motorists and highway maintenance personnel owing to a variety of natural hazards. Hazards include snow and ice, avalanching snow, and blowing and drifting snow. The conditions call for attendant need for incident response. A substantial number of affected routes are low-volume rural winter roads. Configurations have been developed for rural intelligent transportation system (ITS) technology that can detect hazards and provide, autonomously and in real time, warnings to and traffic control actions for motorists, highway maintainers, and incident responders for roadway natural hazards. These warnings include on-site traffic control signing and road closure gates, in-vehicle audio alarms for agency maintenance and patrol vehicles, and notification to highway agency maintenance facilities or centralized multiagency dispatchers. These actions and notifications are initiated automatically from the remote rural sites and via manual intervention from off-site personnel, well removed from the rural roadway corridor itself. About 5 years of experience have been accumulated in using these rural ITS natural-hazard reduction systems, including snow avalanche detection and warning systems on Loveland Pass, Colorado; Hoback Canyon, Wyoming; and Banner Summit, Idaho. Automated road closure gates on the Teton Pass in Idaho and Wyoming now allow for remote road closure during heavy snow events. These cost-effective ITS natural-hazard systems are highly exportable for other processes that affect rural low-volume roadways, including landslide, flooding, high surf, high winds, loss of visibility, wildlife, and other natural hazards of this type.

AbstractEmergency department visitation data were analyzed using a matched-pair, retrospective cohort method to estimate the effects of winter storms on fall-related injury risks for a midsized urban community in Ontario, Canada. Using a unique definition and classification of winter storm events and dry-weather control periods, relative risks of injury were estimated for total falls and two subcategories (same-level falls involving ice and snow; all other falls) across two storm event types (snowfall only; mixed precipitation). Winter storms were associated with 38% and 102% increases in the mean incidence of same-level falls involving ice and snow during snow events and freezing-rain events, respectively. The incidence of other types of falls was slightly but significantly less during snow events relative to dry-weather control periods. Findings suggest that walking is not safer than driving during winter storms, as same-level falls involving ice and snow accounted for 64% more of the injury burden than motor vehicle collisions. Significant reductions in mean relative risk estimates for fall-related injuries were apparent over the 2009–17 study period indicating possible long-term shifts in exposure, sensitivity, and/or risk-mitigating decisions, actions, and behavior. Consistent and significant effects of government-issued weather warning communications on risk outcomes were not found. Practitioners engaged in developing injury prevention strategies and related public risk messaging, in particular winter weather warnings and advisories, should place additional emphasis on falls and multimodal injury risks in communications related to winter storm hazards.

An experiment was conducted in the road district of Kuopio in the winters of 1992–1993 and 1993–1994 in which the use of salt in winter maintenance on rural main roads was reduced to 1 to 2 T/road kilometer from the approximately 10 T of salt that typically had been used per road kilometer in similar conditions in recent years. On the experimental roads, salting was replaced by sanding. The cost of winter maintenance on the experimental roads increased by 20 percent on average, and the increase was higher on roads with higher traffic volumes. Slippery conditions due to ice and snow on the road surface were twice as frequent (30 to 40 percent of the time) on the experimental roads as on the control roads in the neighboring road district. There were 27 injury accidents on the experimental roads in the first winter and 25 in the second. This was about the same as the average of the five previous winters. Because the accident trend on other roads in the same time was decreasing, it was concluded that the experiment increased the number of injury accidents by approximately 20 percent on most experimental road sections. Reduced salting decreased the sodium and chloride concentrations in the needles of roadside pine trees. There were also indications of decreased sodium and chloride concentrations in groundwater. Three quarters of the population in the area was pleased with the experiment.

В статье представлен анализ существующих средств определения прочности снежно-ледовых образований, выявлены их недостатки, преимущества и отличительные способности. Целью данной работы является разработка компактных средств измерения прочности компонентов дорожных покрытий и обеспечения контроля качества уплотнения полотна сооружаемых зимних дорог по глубине покрытия. Предложено техническое решение, которое позволяет достичь более высокого технического результата по сравнению с известными аналогами, который заключается в повышении точности измерений, упрощении фиксации шарового элемента в корпусе, обеспечении фиксации подвижных элементов при транспортировке и расширении функциональных возможностей за счет определения прочности на поверхности и по глубине снежного покрова с наконечниками разного профиля, а также позволяет снизить стоимость изготовления и трудоемкость работ при измерениях. Предложенный прибор (твердомер) позволяет расширить область применения, как для свежевыпавшего снега, так и для лежалого, за счёт применения разных нижних поверхностей профиля наконечников в виде конуса, цилиндра или шара. Шаровая поверхность увеличивает площадь соприкосновения нижней поверхности его со снежными образованиями для свежевыпавшего снега. Прибор спроектирован, изготовлен и позволяет определять прочностные свойства снежно-ледовых образований при выполнении научно-исследовательских работ. The article presents an analysis of the existing means for determining the strength of snow-ice formations, reveals their disadvantages, advantages and distinctive abilities. The purpose of this work is to develop compact means for measuring the strength of road pavement components and ensuring quality control of the compaction of the roadbed of winter roads under construction by the depth of the pavement. A technical solution is proposed that allows achieving a higher technical result in comparison with known analogues, which consists in increasing the measurement accuracy, simplifying the fixing of the ball element in the housing, ensuring the fixation of the moving elements during transportation and expanding the functionality by determining the strength on the surface and in depth snow cover with tips of different profiles, and also allows you to reduce the manufacturing cost and laboriousness of work during measurements. The proposed device (hardness tester) allows you to expand the field of application, both for freshly fallen snow, and for old, due to the use of different lower surfaces of the profile of the tips in the form of a cone, cylinder or ball. The spherical surface increases the contact area of ​​its lower surface with snow formations for freshly fallen snow. The device has been designed, manufactured and allows to determine the strength properties of snow-ice formations during scientific research.

Canadian municipalities are increasingly choosing to achieve bare pavement (BP) for snow and ice control during fall/winter seasons. When a snowstorm event is forecasted, one strategy is to apply anti-icing chemicals to the pavement surface to prevent the snow and ice from forming a bond with the road surface. Such an approach facilitates a more efficient plowing operation and reduces the amount of deicing chemicals needed to achieve BP. This study assesses the safety performance of achieving BP using anti-icing compared with the traditional reactive winter road maintenance (WRM) approach on urban roads using the before-and-after Empirical Bayes technique. Results suggest that achieving BP significantly reduces all collision types and severities on midblocks with a reduction value in the range of 13.7% to 19.7%. Attaining BP at intersections was found to be very effective in reducing injury collisions with an estimated reduction of 12.5%. When sites were grouped based on a WRM priority-basis, it was found that anti-icing was effective for reducing the majority of collision types and severities at the different priority levels with reductions ranging from 8.7% to 49.83% on midblocks and between 5.37% and 13% at intersections. All reductions were statistically significant. The monetary benefits of the reductions in property-damage only and nonfatal injury collisions were estimated at 60 million Canadian dollars using a 1.92% interest rate and a 2-year service life. These findings provide unequivocal evidence that achieving BP using anti-icing can lead to significant societal safety benefits that economically translate to huge collision cost savings.

De-icing agents (ice and snow control materials) are applied to prevent ice and snow deposits on the roads in winter period. The extensive use of de-icing agents in countries with cold climate creates problems for the environment. In this study, the dynamics of de-icing salt concentrations in sod-podzolic soil was revealed in laboratory and field experiments. Twelve de-icing agents of different chemical groups (chlorides, acetates and formates) were studied. Under laboratory conditions, application of high doses of chloride reagents led to an increase of salt concentration in soil up to a level of slightly saline soils. Contaminated soils had salt levels high enough to be toxic to plants and soil microorganisms. However, under field conditions, soil salinity eventually decreased due to salt washout by atmospheric precipitation. By the end of the growing season, salt concentration corresponded to a background level. The decrease in salt concentration was accompanied by a decrease in soil toxicity. Acetate and formate de-icing agents demonstrated the least environmental effect. Our results suggest that magnesium chloride was the least harmful among the de-icers of chloride group while the most commonly used road de-icing salt sodium chloride was the most persistent and toxic to terrestrial plants and soil microbiota.

This study investigated the potential for underplanting 1 + 0 and 1 + 1 northern red oak (Quercusrubra L.) in conjunction with a two-cut shelterwood harvest of a low-quality, ridgetop, tolerant hardwood stand in central Ontario. Growth patterns were followed for 6 years; herbicide (glyphosate) application and prescribed fire (two burns, 3 years apart) were used as competition control measures in an experimental design that tested all possible combinations of stock type, competition control, and clipping 2 years after planting. Six years after outplanting the mean height attained across all treatments for 1 + 0 stock was 76 cm and for 1 + 1 stock, almost 90 cm. Depending upon treatment, some individuals were almost 3 m tall. In the presence of heavy deer (Odocoileusvirginianus Zimmerman) browsing, competition control of any type does not appear to be warranted. Clipping also does not appear to be advantageous. We can speculate that competition control made seedlings more susceptible to browsing by deer or damage by heavy snow and ice accumulation. The competitive ability of red oak on these sites is such that it will respond well to even late release from normal competition resulting from overstory disturbance (i.e., control treatment). The general technique for establishment of oak in this manner appears to be logical for these site conditions, but further investigation is necessary to address the direct impact of browsing pressure on seedling growth and the potential for similar silvicultural prescriptions on more marginal oak sites.

Concrete bridge decks are prone to ice accumulation. Bridge decks freeze before the roads approaching them freeze, making wintry highway travel treacherous. Road salts and deicing chemicals are effective for ice removal but cause damage to concrete and corrosion of reinforcing steel in concrete bridge decks. The resulting rapid degradation of existing concrete pavements and bridge decks is a major concern to transportation and public-works officials. The use of insulation materials for ice control and electric or thermal heating for deicing have been attempted, with unsatisfactory results. Conductive concrete is a cementitious admixture containing electrically conductive components to attain high and stable electrical conductivity. Due to its electrical resistance and impedance, a thin conductive concrete overlay can generate enough heat to prevent ice formation on a bridge deck when connected to a power source. In 1998, Yehia and Tuan, at the University of Nebraska–Lincoln, developed a conductive concrete mix specifically for bridge deck deicing. In this application, a conductive concrete overlay is cast on the top of a bridge deck for deicing or anti-icing. The mechanical and physical properties of the conductive concrete mix after 28 days have met ASTM and AASHTO specifications. Two concrete slabs were constructed with a 9-cm (3.5-in.) conductive concrete overlay for conducting deicing experiments in the natural environment. Deicing and anti-icing experiments were conducted in five 1998 snowstorms. Average power of about 590 W/m2 (55 W/ft2) was generated by the conductive concrete overlays to prevent snow and ice accumulation.

Different risks are associated with the operation and maintenance of wind farms in cold climate regions, mainly due to the harsh weather conditions that wind farms experience in that region such as the (i) increased stoppage rate of wind turbines due to harsh weather conditions, (ii) limited accessibility to wind farms due to snow cover on roads, and (iii) cold stress to workers at wind farms. In addition, there are risks that are caused by wind farms during their operation, which impact the surrounding environment and community such as the (iv) risk of ice throw from wind turbines, (v) environmental risks caused by the wind farms, and (vi) social opposition risk to installing wind farms in cold climate regions, such as the Arctic. The analysis of these six risks provides an overall view of the potential risks encountered by designers, operators, and decision makers at wind farms. This paper presents a methodology to quantify the aforementioned risks using fuzzy logic method. At first, two criteria were established for the probability and the consequences of each risk; with the use of experts’ judgments, membership functions were graphed to reflect the two established criteria, which represented the input to the risk analysis process. Furthermore, membership functions were created for the risk levels, which represented the output. To test the proposed methodology, a wind farm in Arctic Norway was selected as a case study to quantify its risks. Experts provided their assessments of the probability and consequences of each risk on a scale from 0–10, depending on the description of the wind farm provided to them. Risk levels were calculated using MATLAB fuzzy logic toolbox and ranked accordingly. Limited accessibility to the wind farm was ranked as the highest risk, while the social opposition to the wind farm was ranked as the lowest. In addition, to demonstrate the effects of the Arctic operating conditions on performance and safety of the wind farm, the same methodology was applied to a wind farm located in a non-cold-climate region, which showed that the risks ranked differently.

INTRODUCTION Winter snow and ice can have a significant impact on our mobility, whether on foot or by car. Alongside plowing, arguably the greatest tool in combating snow and ice is salt. The most commonly used salt for winter maintenance is Sodium Chloride (NaCl), the same salt used in food and water softeners, is applied to roads, sidewalks, and parking lots as it is an effective deicer when temperatures are between 0°C and −12°C. Studies have shown that deicing with salt reduces accidents by 88% and injuries by 85% (Salt Institute 2017). The effectiveness of road salt, as well as its relative affordability, means that as much as four million tonnes may be applied annually in Canada for deicing (Environment Canada 2012). However, while salt is relatively inexpensive to purchase, there are a number of external costs that are becoming increasingly apparent. These include corrosion of vehicles and infrastructure like concrete, bridges, and water mains; damage and staining to the interior and exterior of buildings; impacts to roadside vegetation and soils; and the contamination of fresh water. In fact, the environmental impacts are such that it prompted Environment Canada to propose that winter salt be considered a toxic substance primarily due to the quantity that is applied annually (Environment Canada 2001). The Lake Simcoe watershed, approximately 3,400km2 in size, is situated just 20km north of Toronto, Ontario, with the southern portion of the watershed being considered part of the Greater Toronto Area (GTA), the most populous metropolitan area in Canada. As part of the GTA, the Lake Simcoe watershed has experienced and continues to experience considerable growth, and with this growth comes an increase in the amount of impervious surfaces requiring winter salting. Indeed, chloride has been showing a strong increasing trend in the urban creeks and in Lake Simcoe itself over the last 30 years. Even rural creeks are showing an increasing trend, albeit not as severe, nor are the concentrations of chloride reaching the same levels (LSRCA 2015). The highest chloride level recorded in a Lake Simcoe tributary was 6,120mg/l in the winter of 2013. Chloride guidelines for the protection of aquatic ecosystems utilize a guideline of 120mg/L for chronic exposure and 640mg/L for acute exposure (CCME 2011). While the high value recorded in the Lake Simcoe tributary greatly exceeds these guidelines, it is still drastically lower than values being recorded in larger, intensively urbanized catchments such as Cooksville Creek in Mississauga, Ontario, which sees concentrations in excess of 20,000 mg/L, the concentration of sea water, nearly every winter (Credit Valley Conservation personal comm). Similarly, in July of 2011 a small population of Atlantic blue crabs, a marine species, was found surviving in Mimico Creek in Toronto (Toronto Star: May 26, 2012). That a marine species was able to survive in this fresh water creek in summer demonstrates that the impacts of winter salt are not just limited to winter but are impacting shallow groundwater and thus summer baseflow, maintaining high chloride concentrations year round. The same is being seen in some urban creeks in the Lake Simcoe watershed, with summer baseflow concentrations exceeding the chronic guideline and trending upwards (LSRCA unpublished). While not yet as extreme as rivers in the more densely urbanized parts of the GTA, these examples foreshadow what is in store for Lake Simcoe rivers if current winter salt practices continue along with the projected urban growth. During the winter of 2012 an estimated 99,300 tonnes of salt was applied in the Lake Simcoe watershed, an amount that equals nearly 250kg of salt per capita, or ~3 times the average person's body weight in salt. This estimate was generated through a survey of local road agencies along with the total area of commercial/institutional parking lots within the watershed. The exercise served to highlight a knowledge gap around application practices and rates in commercial/institutional parking lots. The majority of road agencies were found to record annual volumes, application dates and rates whereas literature values range from 10–40% of the salt applied in a catchment come from commercial/institutional parking lots (Perera et al, 2009; Trowbridge et al, 2010; Lake Simcoe Region Conservation Authority, 2015), and a survey of winter maintenance contractors cite an average value of approximately 58g/m2/application (Fu et al, 2013) ( Figure 1 ). [Figure: see text] While these values were used in the estimation as they were the best available, observational data suggested these may be on the conservative side ( Figure 2 ). [Figure: see text] Therefore, monitoring of a 14 ha commercial lot was undertaken for the winters of 2014/15, 2015/16, and 2016/17 to better quantify the amount of salt coming from this type of land use. The winters of 2014/15 and 2016/17 saw similar applications of 1,067 and 1,010 tonnes applied respectively, while the mild winter of 2015/16 saw 556 tonnes applied. While the amounts varied somewhat each winter, the impacts downstream were consistent. Maximum concentrations recorded in the melt water reached 3.5 to 4 times the salt concentration of sea water every winter, equating to chloride concentrations of 70,000mg/L to 85,000mg/L; two orders of magnitude above the water quality guideline. As with most parking lots constructed in the last two decades, the runoff from this parking lot is captured in a stormwater pond prior to entering the receiving watercourse. Interestingly, the winter salt also caused persistent chemical stratification in the permanent pool of the pond. The pond was monitored with continuous monitors for the ice free period of 2015 and 2016 (April to December) during which the bottom water chloride concentration remained distinct from the surface chloride concentration, indicating stratification ( Figure 3 ). This has two significant implications; first of which is that this pond, and therefore many other ponds like it, may not be functioning as designed which is leading to diminished performance (McEnroe 2012, Marsalek 2003). Second is that ponds are acting as salt reservoirs, slowly releasing salt year round and contributing to river chloride concentrations that continually exceed the chronic exposure guideline and thereby exposing aquatic life to harmful concentrations during sensitive life cycle stages. [Figure: see text] To determine the extent to which the catchment land use type impacts stormwater ponds, chemical profiles were measured on three ponds in February 2017. The catchments included the 24.6 ha commercial catchment with 14 ha of salt application surface, an institutional catchment (14.3 ha) with 6 ha of salt application area that includes parking lots and roads, and a 16.4 ha residential catchment with 3 ha of salt application area comprised of tertiary municipal roads. Interestingly, all three ponds showed chemical stratification, with the severity of the stratification and highest chloride concentrations relating to the amount of salt application area in the catchment. The residential pond yielded a maximum chloride concentration of 3,115mg/L in the bottom waters, the institutional yielded 16,144mg/L, and the commercial yielded 25,530 mg/L with chloride concentrations in the bottom 0.5m of the pond exceeding that of sea water. The maximum chloride concentration recorded in the receiving watercourse downstream of the commercial lot was measured at 5,406 mg/L, well in excess of the acute guideline of 640 mg/L. These results highlight that commercial parking lots are not only receiving a significant volume of salt but are also having the most dramatic impacts on receiving stormwater infrastructure and watercourses.

In all countries where, with regard to climatic conditions, the occurrence of ice on the roads is possible, great efforts are made to minimize the loss of friction on the pavement surface, thereby ensuring continuity and safety of traffic and minimizing human casualties and material losses. Modern road maintenance in the winter period is based on finding a solution to reduce the freezing point of water by creating chemical solutions and breaking the bond between ice and pavement. However, the use of various chemicals and abrasive materials, especially in uncontrolled quantities, can have serious environmental consequences. This paper presents the most commonly used materials for preventing ice, as well as underlines negative impacts and recommendations for mitigation of environmental threats.

While Autonomous Vehicles (AVs) are potentially the future of transportation, one of the main issues that need to be addressed is their behaviour and response to adverse weather conditions. Herein we propose a research frame to understand and mitigate the impact of weather stressors (wind, rain, snow, ice, and fog) on AVs. A recently launched initiative to design and engineer an indigenous Canadian road vehicle serves as a background for this intended framework. The proposed frame consists of: (i) on-road testing and numerical (CFD) simulations to derive statistically significant critical weather conditions (weather design cases, WDCs); (ii) simulation of these weather conditions in the ACE climatic wind tunnel at Ontario Tech University, Canada in order to (iii) identify adaptive controls to minimize the effects of the WDCs on vehicles improving their aerodynamics, safety, and sensor functionality. This framework is intended to: (i) provoke discussions among the AV industry and research stakeholders in Canada and elsewhere and (ii) provide a context for future research in related areas such as AV aerodynamics, maneuverability, weather impacts (e.g. wind, rain, snow, ice and fog), sensors and soiling.