Saskatchewan producers traditionally overwinter their cattle in pens in the yard. The practice of winter feeding of cattle directly in the field is increasing in popularity leading to concerns about increased nutrients being deposited in soil and potentially lost in runoff water and to ground water. In 2008/2009 an experiment was conducted to observe the effect of in-field winter feeding of cows on the nutrients in spring snowmelt run-off. Approximately 100 cattle were baled grazed on a Russian wild ryegrass pasture at a stocking rate of 2240 cow-days ha-1 for 88 d during the winter at the Western Beef Development Center at Lanigan, SK. The spring 2009 ponded water was sampled from four basins in the control (no cattle were present) and four basins in the winter feeding treatment from the end of March to mid-April. Ground water samples from two piezometers in the control and two in the winter feeding area were gathered from the start of runoff until the middle of summer. Soil samples (0-10 cm) were collected in the fall 2008 before winter feeding and again in the spring 2009 after winter feeding on both the control and treated areas to examine the influence of winter feeding on soil nutrients. Orthophosphate-P and ammonium-N concentrations were elevated to levels up to 19.9 mg PO4-P L-1 and 102.3 mg NH4-N L-1 respectively in run-off from the winter feed treatment basins compared to the controls (2.1 mg PO4-P L-1 and 1.72 mg NH4-N L-1). Nitrate-N concentrations in snowmelt run-off water were similar from the winter-fed areas (0.008 mg NO3-N L-1 to 0.739 mg NO3-N L-1) and the control (0.001 mg NO3-N L-1 to 1.046 mg NO3-N L-1). This is explained by lack of sufficient time and temperature for organic N, urea and ammonium in the urine and fecal matter to convert to nitrate. In the ground water there was a slight increase in nutrient ion concentration in the winter feed basins compared to the control. Soil sampled in the spring from the winter feeding site had higher soluble nitrate, ammonium and phosphorus compared to the control. The soluble and exchangeable forms of phosphorus in the soil were lower compared to the fall soil samples for the control and winter feeding site, possibly due to immobilization by plant and microbial uptake in the spring. Caution should be used when selecting sites for in-field winter feeding system so the run-off water does not reach sensitive water bodies.

The Sudbury, ON, Canada region has been the site of metal mining and processing operations for more than 100 years. The study site for my thesis, Junction Creek, flows southwest through the City of Greater Sudbury and receives cumulative inputs including from the Garson Mine wastewater treatment plant (WWTP), Nolin Creek WWTP (stormwater) and CVRD Inco Limited WWTP (process water) as well as effluent from municipal WWTPs and untreated urban runoff, aerial deposition and historical contamination from multiple sources. Elevated levels of ammonia, Ni, Cu, Co, Pb and As, as well as reduced benthic invertebrate community diversity and density have been observed in the Junction Creek system below certain mine inputs. In addition, the Sudbury region has cold winters, with average daily air temperatures below 0°C from November to March.<p> The winter stress syndrome hypothesis proposes that the combination of winter conditions and contaminants (acting as physiological stressors) in the aquatic environment could reduce fish condition and deplete energy (lipid) reserves to the point of decreased survival, thus negatively impacting wild fish populations. However the winter stress syndrome hypothesis has rarely been tested in the field. I hypothesized that juvenile fish challenged with a physiological stressor (treated wastewater) in combination with winter conditions would have decreased growth and energy stores as a result of increased metabolism.<p> The approach I used to examine the potential effects of treated metal mine and municipal wastewaters on bioenergetics and growth, as they related to overwinter survival potential and the winter stress syndrome, of juvenile fish was a combination of a field study and a laboratory experiment. The first objective was to test the winter stress syndrome hypothesis under field conditions. Juvenile fathead minnows (Pimephales promelas), creek chub (Semotilus atromaculatus) and white sucker (Catostomus commersoni) were collected in fall and the following spring from sites along Junction Creek, Sudbury, ON downstream of two metal mining wastewater treatment plants as well as a municipal wastewater treatment plant. The second objective was to test the winter stress syndrome hypothesis in the laboratory by determining the effect of diluted (45 percent) treated CVRD Inco Limited wastewater effluent (CCWWTP) on juvenile fathead minnow growth and energy storage under simulated summer and winter conditions of reduced temperature, photoperiod and food ration. The effect on growth and energy storage of exposure to environmentally relevant ammonia concentrations was also assessed. In both the field and laboratory portions of this study, overwinter survival potential was assessed indirectly through measurements of growth (length, weight, muscle RNA/DNA ratio, muscle proteins) and energy stores (whole body triglycerides). There were inconsistent effects between the field study and the laboratory experiment. In contrast to my hypothesis, fathead minnows in the field study were larger with greater triglyceride stores at exposure sites compared to the reference site. White suckers were smaller at exposure sites but did not differ in triglycerides among sites and creek chub had no clear trend. For the laboratory portion of this study, only fathead minnows were used. After a 90 day exposure to reference or diluted CCWWTP water under simulated winter or summer conditions, juvenile fathead minnows raised in winter CCWWTP water (4°C) had lower whole body triglyceride concentration than those raised in winter reference water. There was no difference in triglycerides in fathead minnows raised in diluted CCWWTP or reference water under summer conditions. This lends support to the winter stress syndrome hypothesis, but the traditional measures of growth showed no significant differences in any of the treatments. In a separate experiment, fathead minnows were exposed from 10-100 days post hatch to graded concentrations of ammonia (0.02 to 0.40 mg unionized NH3/L) under summer conditions only. There was no effect of ammonia exposure on growth parameters, but a significant increase in total body triglycerides at the highest exposure concentration (0.40 mg/L) was observed.<p> The results of this study emphasize that laboratory-based hypotheses must be tested in the field to determine their environmental significance. The winter stress syndrome may not apply to northern fish adapted to living and feeding in colder climates and was not strongly supported by my study.

This thesis is concerned with the development of a new measurement device for the realistic assessment of braking capability of landing airplanes for winter runways. Landing represents one of the most safety-critical phases of aircraft operation. Aircraft runway excursion incidents occur due to the unpredictability of the runway pavement condition. This is especially true during winter time when the runway is often covered by deformable contaminants. Several accidents are discussed that list the deteriorated condition of the runway pavement and the inability to accurately report this condition as the main causes for the excursions. The accuracy of the approaches currently adopted by the airport authorities around the world to monitor the condition of the runway pavement are evaluated. The conventional and current practice of runway condition monitoring is focused on identifying the maximum tire-pavement frictional drag mu value and often neglects the characteristics of actual aircraft brake control system as well as the comprehensive effects coming from various factors such as deformable contaminants on the winter runway. The braking availability tester discussed here is designed to take a different approach for the realistic assessment of braking availability of landing aircrafts. The main idea of this device is to mimic the braking operation of actual aircrafts as closely as possible by incorporating the same brake mechanism and the brake control system used in existing aircrafts. The architecture of the device from the ground-up including the suite of sensors, the structure of the wheel, important actuators, and the real-time brake control system are discussed in detail. More importantly, the operational principles of the braking availability tester (BAT) are outlined which help one understand how the system works together. A new method to quantify the braking availability on the runway using the BAT is explained. The testing and data collection strategy for implementing this technique is also outlined. Additionally, the results from preliminary tests are presented to verify the functionality of the BAT. The results are used to verify that the BAT operates with the brake control system of an aircraft. Finally, experimental data sets from dry and contaminated pavement testing are presented to show the effect of different weather conditions on the operation of the BAT.

Winter road maintenance activities are crucial for maintaining the accessibility and traffic safety of the road network at northerly latitudes during winter. Common winter road maintenance activities include snow ploughing and the use of anti-icing agents (e.g. road salt, NaCl). Since the local weather is decisive in creating an increased risk of slippery conditions, understanding the link between local weather and conditions at the road surface is critically important. Sensors are commonly installed along roads to measure road weather conditions and support road maintenance personnel in taking appropriate actions. In order to improve winter road maintenance, more precise information about road surface conditions is essential. In this thesis, different methods for estimation of road weather are developed, discussed and tested. The methods use the principles of infrared thermometry, image analysis and spectroscopy to describe ice formation, snow accumulation and road surface wetness in specific patches or along road sections. In practical applications, the methods could be used for better planning of snow clearing operations, forecasting of ice formation and spreading of road salt. Implementing the proposed methods could lead to lower maintenance costs, increased traffic safety and reduced environmental impact. / <p>QC 20121116</p>

Traffic crashes tend to occur at relatively greater frequencies at particular locations, at particular time periods, and for particular subsets of drivers and vehicles. It is well recognized among the road safety community that crash-risk is highly elevated when inclement weather conditions occur in the winter. To present, most of the road safety studies focus on event-based analysis or seasonal analysis and give little attention to explore high-risk conditions at the daily temporal scale. The purpose of the study is to advance our understanding of high-risk crash conditions at the daily level and their occurrences in Southern Ontario, Canada. The study explores different definitions of high-crash days, and quantifies the influences of weather conditions, risk exposure, months and timing of precipitation on the likelihood of a high-crash day occurring using binary logistic regression model. Additionally, an approach for estimating the relative risk exposure using available traffic count data has also been developed. The results of the study show a small proportion of high-crash days are responsible for a considerable amount of traffic crashes during the winter. The risk of traffic crash is twice as high on high-crash days in comparison to non-high-crash days. The modeling approach well-fits the data and shows that winter weather conditions have significant influence on high-crash days with results being mostly consistent across the four study areas, Toronto, the Area Surrounding Toronto, London and the Area Surrounding London. Low temperature, heavy snowfalls, high wind speeds, high traffic volumes, early winter months, occurrence of precipitation in both morning and evening increase the odds of high-crash days to a large extent. The results of study could help to pre-schedule traffic operation and enforcement, to effectively distribute road safety resources and personnel, and to create situational awareness among road users and other stakeholders.

Scheduling of winter maintenance operations such as plowing or salting is a difficult and complex problem. Proper selection and timing of such operations is critical to their effectiveness, however scheduling decisions must often be made with strict time and resource limitations imposed upon them. A decision support system which analyses current road conditions and makes scheduling suggestions based on them would be a valuable step toward improving the quality of treatment, while simultaneously reducing the burden of scheduling on maintenance managers. This thesis proposes a real-time scheduling model based on an Operations Research framework that can be used by maintenance managers to develop and evaluate alternative resources allocation plans for winter road maintenance operations. The scheduling model is implemented as an Integer Linear Program and is solved using off-the-shelf software packages. The scheduling model takes into account a wide range of road and weather condition factors such as road network topology, road class, weather forecasts, and contractual service levels, and produces a vehicle dispatch schedule that is optimal with respect to operating costs and quality of service. A number of heuristics are also explored to aid in efficient approximations to this problem.

Scheduling of winter maintenance operations such as plowing or salting is a difficult and complex problem. Proper selection and timing of such operations is critical to their effectiveness, however scheduling decisions must often be made with strict time and resource limitations imposed upon them. A decision support system which analyses current road conditions and makes scheduling suggestions based on them would be a valuable step toward improving the quality of treatment, while simultaneously reducing the burden of scheduling on maintenance managers. This thesis proposes a real-time scheduling model based on an Operations Research framework that can be used by maintenance managers to develop and evaluate alternative resources allocation plans for winter road maintenance operations. The scheduling model is implemented as an Integer Linear Program and is solved using off-the-shelf software packages. The scheduling model takes into account a wide range of road and weather condition factors such as road network topology, road class, weather forecasts, and contractual service levels, and produces a vehicle dispatch schedule that is optimal with respect to operating costs and quality of service. A number of heuristics are also explored to aid in efficient approximations to this problem.

In countries with severe winters such like Canada, winter road maintenance (WRM) operations, such as plowing, salting and sanding, play an indispensible role in maintaining good road surface conditions and keeping roads safe. WRM is, however, also costly, both monetarily and environmentally. The substantial direct and indirect costs associated with WRM have stimulated significant interest in quantifying the safety and mobility benefits of winter road maintenance, such that systematic cost-benefit assessment can be performed. A number of studies have been initiated in the past decade to identify the links between winter road safety and factors related to weather, road, and maintenance operations. However, most of these studies have focused on the effects of adverse weather on road safety. Limited efforts have been devoted to the problem of quantifying the safety benefits of winter road maintenance under specific road weather conditions. Moreover, the joint effects of and complex interactions between road driving conditions, traffic and maintenance and their impact on traffic safety have rarely been studied. This research aims to determine the effect of WRM on road safety during snow storm events and develop models that can be used to quantify the safety benefit of alternative winter road maintenance policies, strategies and practices. Two integral aspects of collision risk were investigated, namely, collision frequency and severity. Collision frequency models were developed using winter storm collision data compiled for six winter seasons (2000 to 2006) for a total of 31 highway routes across Ontario. A comprehensive measure, namely, road surface condition index (RSI), was proposed to represent the road surface conditions during a variety of snow events. RSI was used as a surrogate measure to capture the effects of WRM. Other factors related to weather, traffic and road features were also accounted for in the analysis. Problems associated with data aggregation were also investigated. For this purpose, two different datasets were formed, namely, event-based data (EBD) which aggregates data by snow storm events and hourly based data (HBD) which includes hourly records of collision counts and other related factors. These two data sets of different aggregation levels were then used to investigate the effects of data aggregation and correlation (within – event) as well as to develop models for different purposes of benefit analyses. For EBD, Negative Binomial models and Generalized Negative Binomial models were calibrated whereas for HBD, Generalized Negative Binomial models and multilevel Poisson Lognormal models were calibrated. Generalized Negative Binomial models were found to best fit the data for both datasets. It was found that addition of site specific variables improves model fit. RSI and exposure were found significant for all the models and datasets. Weather factors such as visibility, wind speed, precipitation, and air temperature were also found to have statistically significant effects on collision frequency. All the models were consistent in terms of effects of different variables. The EBD models are useful to quantify the effect of different maintenance service standards and policies with limited information on the details of the weather events and traffic. On the other hand, HBD models have a higher level of reliability capable of providing more accurate estimates on road accidents. As a result, they are useful for determining the effects of different treatment operations. Several examples were employed to demonstrate the application of the developed models, such as quantifying the benefits of alternative maintenance operations and evaluating the effects of different service standards using safety as a performance measure. To enable a comprehensive risk analysis, collisions under both all-weather conditions and snow storm conditions over the six winter seasons were analyzed to identify the relationship between collision severity and various factors related to road weather and surface conditions, road characteristics, traffic, and vehicles etc., on collision severity. A multilevel modeling framework was introduced to capture the inherent hierarchy between collisions, vehicles and persons involved within the collision data. For each collision data set, three alternative severity models, namely, multinomial models, ordered logit models and binary logit models, were calibrated and compared. It was found that multilevel multinomial logit models were best fit to the data. Moreover issues related to different levels of aggregation were also discussed and results from occupant based data were found to be more reasonable and in line with general literature. Different individual, vehicle, environment and accident location factors were found to have a statistically significant effect on the injury severity levels. Contributing factors at the individual and vehicle levels include driver condition, driver sex, driver age, position in vehicle, use of safety device such as seat belt, vehicle type, vehicle age and vehicle condition. Roadway and environment factors include number of lanes, speed limit, road alignment, RSI/road surface condition, wind speed, and visibility. Other factors include light, and traffic volume. Two case studies were conducted to demonstrate the application of the developed models in conjunction with the accident frequency models for cost benefit analysis. This research was the first to investigate the direct link between road surface conditions and collisions at an operational level. It has been shown that the developed models are capable of evaluating alternative winter road maintenance policies and operations and assessing the safety benefit of a particular winter road maintenance strategy or decision. This research is also the first to conduct an in-depth analysis on the problem of winter road safety at a disaggregate level that captures detailed temporal variation (e.g., hourly and by storm event)) within small spatial aggregation units (road sections corresponding to actual patrol routes). The safety models developed from this research could be easily incorporated into a decision support tool for conducting what-if analysis of alternative winter road maintenance policies and methods. Moreover these models could provide a mechanism to estimate road safety level based on road surface as well as weather and traffic conditions and therefore could potentially be used for generating safety related information for travelers as part of a winter traffic management scheme. Directions for future work are also provided at the end of this document.

The Sudbury, ON, Canada region has been the site of metal mining and processing operations for more than 100 years. The study site for my thesis, Junction Creek, flows southwest through the City of Greater Sudbury and receives cumulative inputs including from the Garson Mine wastewater treatment plant (WWTP), Nolin Creek WWTP (stormwater) and CVRD Inco Limited WWTP (process water) as well as effluent from municipal WWTPs and untreated urban runoff, aerial deposition and historical contamination from multiple sources. Elevated levels of ammonia, Ni, Cu, Co, Pb and As, as well as reduced benthic invertebrate community diversity and density have been observed in the Junction Creek system below certain mine inputs. In addition, the Sudbury region has cold winters, with average daily air temperatures below 0°C from November to March.<p> The winter stress syndrome hypothesis proposes that the combination of winter conditions and contaminants (acting as physiological stressors) in the aquatic environment could reduce fish condition and deplete energy (lipid) reserves to the point of decreased survival, thus negatively impacting wild fish populations. However the winter stress syndrome hypothesis has rarely been tested in the field. I hypothesized that juvenile fish challenged with a physiological stressor (treated wastewater) in combination with winter conditions would have decreased growth and energy stores as a result of increased metabolism.<p> The approach I used to examine the potential effects of treated metal mine and municipal wastewaters on bioenergetics and growth, as they related to overwinter survival potential and the winter stress syndrome, of juvenile fish was a combination of a field study and a laboratory experiment. The first objective was to test the winter stress syndrome hypothesis under field conditions. Juvenile fathead minnows (Pimephales promelas), creek chub (Semotilus atromaculatus) and white sucker (Catostomus commersoni) were collected in fall and the following spring from sites along Junction Creek, Sudbury, ON downstream of two metal mining wastewater treatment plants as well as a municipal wastewater treatment plant. The second objective was to test the winter stress syndrome hypothesis in the laboratory by determining the effect of diluted (45 percent) treated CVRD Inco Limited wastewater effluent (CCWWTP) on juvenile fathead minnow growth and energy storage under simulated summer and winter conditions of reduced temperature, photoperiod and food ration. The effect on growth and energy storage of exposure to environmentally relevant ammonia concentrations was also assessed. In both the field and laboratory portions of this study, overwinter survival potential was assessed indirectly through measurements of growth (length, weight, muscle RNA/DNA ratio, muscle proteins) and energy stores (whole body triglycerides). There were inconsistent effects between the field study and the laboratory experiment. In contrast to my hypothesis, fathead minnows in the field study were larger with greater triglyceride stores at exposure sites compared to the reference site. White suckers were smaller at exposure sites but did not differ in triglycerides among sites and creek chub had no clear trend. For the laboratory portion of this study, only fathead minnows were used. After a 90 day exposure to reference or diluted CCWWTP water under simulated winter or summer conditions, juvenile fathead minnows raised in winter CCWWTP water (4°C) had lower whole body triglyceride concentration than those raised in winter reference water. There was no difference in triglycerides in fathead minnows raised in diluted CCWWTP or reference water under summer conditions. This lends support to the winter stress syndrome hypothesis, but the traditional measures of growth showed no significant differences in any of the treatments. In a separate experiment, fathead minnows were exposed from 10-100 days post hatch to graded concentrations of ammonia (0.02 to 0.40 mg unionized NH3/L) under summer conditions only. There was no effect of ammonia exposure on growth parameters, but a significant increase in total body triglycerides at the highest exposure concentration (0.40 mg/L) was observed.<p> The results of this study emphasize that laboratory-based hypotheses must be tested in the field to determine their environmental significance. The winter stress syndrome may not apply to northern fish adapted to living and feeding in colder climates and was not strongly supported by my study.

Saskatchewan producers traditionally overwinter their cattle in pens in the yard. The practice of winter feeding of cattle directly in the field is increasing in popularity leading to concerns about increased nutrients being deposited in soil and potentially lost in runoff water and to ground water. In 2008/2009 an experiment was conducted to observe the effect of in-field winter feeding of cows on the nutrients in spring snowmelt run-off. Approximately 100 cattle were baled grazed on a Russian wild ryegrass pasture at a stocking rate of 2240 cow-days ha-1 for 88 d during the winter at the Western Beef Development Center at Lanigan, SK. The spring 2009 ponded water was sampled from four basins in the control (no cattle were present) and four basins in the winter feeding treatment from the end of March to mid-April. Ground water samples from two piezometers in the control and two in the winter feeding area were gathered from the start of runoff until the middle of summer. Soil samples (0-10 cm) were collected in the fall 2008 before winter feeding and again in the spring 2009 after winter feeding on both the control and treated areas to examine the influence of winter feeding on soil nutrients. Orthophosphate-P and ammonium-N concentrations were elevated to levels up to 19.9 mg PO4-P L-1 and 102.3 mg NH4-N L-1 respectively in run-off from the winter feed treatment basins compared to the controls (2.1 mg PO4-P L-1 and 1.72 mg NH4-N L-1). Nitrate-N concentrations in snowmelt run-off water were similar from the winter-fed areas (0.008 mg NO3-N L-1 to 0.739 mg NO3-N L-1) and the control (0.001 mg NO3-N L-1 to 1.046 mg NO3-N L-1). This is explained by lack of sufficient time and temperature for organic N, urea and ammonium in the urine and fecal matter to convert to nitrate. In the ground water there was a slight increase in nutrient ion concentration in the winter feed basins compared to the control. Soil sampled in the spring from the winter feeding site had higher soluble nitrate, ammonium and phosphorus compared to the control. The soluble and exchangeable forms of phosphorus in the soil were lower compared to the fall soil samples for the control and winter feeding site, possibly due to immobilization by plant and microbial uptake in the spring. Caution should be used when selecting sites for in-field winter feeding system so the run-off water does not reach sensitive water bodies.