Journal articles on the topic 'Leases – Ontario – Greater Toronto Region'

Purpose This paper aims to present a panel data econometric model of the main determinants of house prices in the ten largest census metropolitan areas (CMA) in Ontario, Canada, for the years 2001, 2006 and 2011. The impact of immigration on the housing market in Canada is little researched; however, immigration plays an important role into the economy of Canada. According to Statistics Canada, not only is immigration key to Canada’s population growth but also without immigration, in the next 20 years, Canada’s population growth will be zero. The motivation for this study is the bursting of housing bubbles in some developed countries (e.g. USA). The authors analyze variables that are related to the immigration policy in Canada, accounting also for the impact of the interest rate, income, unemployment, household size and housing supply to analyze housing price determinants. The study investigates the magnitude of the impact of the top three leading categories of immigrants to Canada, namely, Chinese, Indian and Filipino, on the housing prices in Ontario’s largest cities. The results show the main factors that explain home prices over time that are interest rate, immigration, unemployment rate, household size and income. Over the 10-year period from 2001 to 2011, immigration grew by 400 per cent in Toronto CMA, the largest receiving area in Ontario, while the nonimmigrant population grew by 14 per cent. For Toronto CMA, immigrants, income, unemployment rate and interest rate explain the CA$158,875 average home price increase over the 2001-2011 time period. Out of this, the three categories of immigrants’ share of total home price increase is 54.57 per cent, with the corresponding interest rate share 58.60 per cent and income share 11.32 per cent of the total price growth. Unemployment rate contributes negatively to the housing price and its share of the total price increase is 24.49 per cent. Design/methodology/approach The framework for the empirical analysis applies the hedonic pricing model theory to housing sales prices for the ten largest CMAs in Ontario over the years 2001-2011. Following Akbari and Aydede (2012) and O’Meara (2015), market clearing in the housing market results in the housing price as a function of several housing attributes. The authors selected the housing attributes based on data availability for the Canadian Census years of 2001, 2006 and 2011 and the variables that have been most used in the literature. The model has the average housing prices as the dependent variable, and the independent variables are: immigrants per dwelling (Chinese, Indian, and Filipino), unemployment rate, average employment income, household size, housing supply and the interest rate. To capture the relative scarcity of dwellings, the independent variable immigrants per dwelling was used. Findings This study seems to suggest that one cause of high prices in Ontario is large inflows of immigrants together with low mortgage interest rate. The authors focused their attention on Toronto CMA, as it is the main destination of immigrants and comprises the largest cities, including Toronto, Mississauga, Brampton and Oakville. Looking over the 10-year period from 2001 to 2011, the authors can see the factors that impact the home prices in Toronto CMA: immigration, unemployment rate, household size, interest rate and income. Over the period of 10 years from 2001 to 2011, immigrants’ group from China, India and the Philippines account for CA$86,701 increase in the home price (54.57 per cent share of the total increase). Income accounts for CA$17,986 increase in the home price (11.32 per cent share); interest rate accounts for CA$93,103 of the average home price increase in Toronto CMA (58.60 per cent share); and unemployment rate accounts for CA$38,916 decrease in the Toronto average home prices (24.49 per cent share). Household size remain stable over time in Toronto (2.8 average household size) and does not have a contribution to home price change. All these four factors, interest rate, immigrants, unemployment rate and income, together explain CA$158,875 increase in home prices in Toronto CMA between 2001 and 2011. Practical implications The housing market price analysis may be more complex, and there may be factors impacting the housing prices extending beyond immigration, interest rate, income and household size. Finally, the results of this paper can be extended to include the most recent census data for the year 2016 to reflect more accurately the price situation in the housing market for Ontario cities. Social implications The fact that currently, in 2017, the young working population cannot afford buying a property in the Toronto CMA area means there is a problem with this market and a corresponding decrease in the quality of life. According to The Globe and Mail (July 2017), a new pool in 2017 suggested that two in five Canadians believe housing in this country is not affordable for them. Further, 38 per cent of respondents who consider themselves middle or upper class believe in no affordability of housing. The Trudeau Government promised Canadians a national housing strategy for affordable housing. Designing a national housing strategy may be challenging because it has to account for the differential income ranges across regions. Municipal leaders are asking the government to prioritize repair and construct new affordable housing. Another reason discussed in the media of the unaffordability of housing in Toronto and Vancouver is foreign buyers. The Canadian Government recently implemented a tax measure on what it may seem the housing bubble problem: foreign buyers. Following Vancouver, in April 2017, Ontario Government imposed a 15 per cent tax on foreign buyers who are not Canadian citizens or permanent residents. This tax is levied on houses purchased in the area stretching from Niagara Region and Greater Toronto to Peterborough. Originality/value Few studies use Canadian data to explain house prices and analyze the effect of immigration on housing prices. There is not much research on the effect of the immigrants and immigrants’ ethnicity (e.g., Chinese, Indian and Filipino immigrants), on the housing prices in Canada cities. This study investigates the impact of the most prevalent immigrant races (e.g., from China, India and the Philippines) on housing prices, using data for Canadian major cities in Ontario within a panel data econometric framework. This paper fills this gap and contributes to the literature, which analyzes the determinants of housing prices based on a panel of cities in the Canadian province of Ontario.

Introduction To understand the lack of a gradient in mortality by neighbourhood income in a previous study, we used individual-level data from the 1991–2001 Canadian census mortality follow-up study to examine income-related disparities in life expectancy and probability of survival to age 75 years in the City of Toronto and Region of Peel. Methods We calculated period life tables for each sex and income adequacy quintile, overall and separately for immigrants and non-immigrants. Results For all cohort members of both sexes, including both immigrants and non-immigrants, there was a clear gradient across the income quintiles, with higher life expectancy in each successively richer quintile. However, the disparities by income were much greater when the analysis was restricted to non-immigrants. The lesser gradient for immigrants appeared to reflect the higher proportion of recent immigrants in the lower income quintiles. Conclusion These findings highlight the importance of using individual-level ascertainment of income whenever possible, and of including immigrant status and period of immigration in assessments of health outcomes, especially for areas with a high proportion of immigrants.

Abstract. Many stakeholders are seeking methods to reduce carbon dioxide (CO2) emissions in urban areas, but reliable, high-resolution inventories are required to guide these efforts. We present the development of a high-resolution CO2 inventory available for the Greater Toronto Area and surrounding region in Southern Ontario, Canada (area of ∼ 2.8 × 105 km2, 26 % of the province of Ontario). The new SOCE (Southern Ontario CO2 Emissions) inventory is available at the 2.5 × 2.5 km spatial and hourly temporal resolution and characterizes emissions from seven sectors: area, residential natural-gas combustion, commercial natural-gas combustion, point, marine, on-road, and off-road. To assess the accuracy of the SOCE inventory, we developed an observation–model framework using the GEM-MACH chemistry–transport model run on a high-resolution grid with 2.5 km grid spacing coupled to the Fossil Fuel Data Assimilation System (FFDAS) v2 inventories for anthropogenic CO2 emissions and the European Centre for Medium-Range Weather Forecasts (ECMWF) land carbon model C-TESSEL for biogenic fluxes. A run using FFDAS for the Southern Ontario region was compared to a run in which its emissions were replaced by the SOCE inventory. Simulated CO2 mixing ratios were compared against in situ measurements made at four sites in Southern Ontario – Downsview, Hanlan's Point, Egbert and Turkey Point – in 3 winter months, January–March 2016. Model simulations had better agreement with measurements when using the SOCE inventory emissions versus other inventories, quantified using a variety of statistics such as correlation coefficient, root-mean-square error, and mean bias. Furthermore, when run with the SOCE inventory, the model had improved ability to capture the typical diurnal pattern of CO2 mixing ratios, particularly at the Downsview, Hanlan's Point, and Egbert sites. In addition to improved model–measurement agreement, the SOCE inventory offers a sectoral breakdown of emissions, allowing estimation of average time-of-day and day-of-week contributions of different sectors. Our results show that at night, emissions from residential and commercial natural-gas combustion and other area sources can contribute > 80 % of the CO2 enhancement, while during the day emissions from the on-road sector dominate, accounting for > 70 % of the enhancement.

Forested lands in southern Ontario are threatened by a myriad of demands. In order to capture the multi-scale, multi-use and multifunction reality of forests within such intense human-nature interdependent landscapes, an integrative approach to sustainable forest management is necessary. Such forest management may be possible by combining the framework of landscape ecology with an understanding of forest multifunctionality. Within the Greater Toronto Area, the management of forests is provided by several agencies; some are responsible for 1) geological landscapes (e.g., the Niagara Escarpment), 2) for watersheds (e.g., Conservation Authorities) and 3) for political regions (e.g., York Region). In this paper, case studies reflecting important management issues are introduced. Wildlife research is then presented to link these issues to landscape ecology and forest multifunctionality in order to illustrate a means of enhancing sustainable forest management. Key words: landscape ecology, multifunctionality, multifunctional approach, sustainable forest management, Greater Toronto Area, wildlife function, integrative forest management

Bioblitzes are typically 24-hour biological surveys of a defined region carried out by taxonomic specialists, citizen scientists, and the general public. The largest in Canada is the Ontario BioBlitz, an annual event held in the Greater Toronto Area (GTA). Between 2013 and 2016, we examined the feasibility of including lichens and allied fungi in the Ontario BioBlitz. These taxa are often overlooked, understudied, and taxonomically difficult. We completed a bioblitz in each of the four major watersheds in the GTA and recorded 138 species in 72 genera which, combined with all previous collections, totals 180 species in 88 genera in the area. Thirteen of the species we collected are provincially ranked as S1 (critically imperilled), S2 (imperilled), or S3 (vulnerable). We collected Lecanora carpinea for the first time in Ontario. Our results provide a baseline list of GTA lichens that can be used for monitoring. This is one of the first detailed lichen surveys of a major North American urban area and it demonstrates that rapid bioblitz surveys are proficient in capturing lichen diversity despite their inconspicuous nature and the advanced microscopy and chemical analyses required for their identification.

Receiving water quality concerns associated with increased construction activities in recent years in the Greater Toronto Area has prompted the Toronto and Region Conservation Authority (TRCA) to evaluate design criteria for sediment control ponds employed during the construction period. Stormwater management ponds located in the towns of Richmond Hill and Markham were monitored to obtain stormwater runoff quantity and influent-effluent quality data during site development. The ponds were designed and constructed in accordance with the Ontario Ministry of the Environment Stormwater management planning and design manual 2003 for an enhanced level of protection (i.e., 80% total suspended solids removal). A hydrodynamic and sediment-transport model was used to examine the effect of pond geometry on sediment removal efficiency under varying storm events. The monitoring data and the modelling results clearly demonstrate the importance of proper pond size and geometry design. This paper focuses on the effect of the ratio of pond length to pond width in minimizing the short-circuiting effect and improvement of the sediment removal efficiency of stormwater management ponds. The results of this study will be useful in updating the design criteria for stormwater management ponds.Key words: stormwater, management, pond, design, sediment.

Abstract In this study, we sampled stream benthos using rapid bioassessment methods (i.e., D-nets, coarse taxonomy) from sites in and around Toronto, Ontario that represented a range of stream characteristics (e.g., drainage areas). The protocols were developed by or adapted from: (1) Toronto and Region Conservation Authority, (2) Ontario Ministry of Natural Resources, (3) Ontario Benthos Biomonitoring Network/Ministry of the Environment, and (4) Canadian Aquatic Biomonitoring Network/Environment Canada. Summary indices (Hilsenhoff's modified Biotic Index [HBI]; percent of fauna as Ephemeroptera, Plecoptera, and Trichoptera [% EPT]; number of taxa [S]; and Shannon's Diversity Index [H']) calculated from the resulting data were used to evaluate differences between protocols in a series of analyses including analysis of variance and variance components analysis. The study found that sampling method was an unimportant source of variation in summary index values relative to other factors such as the stream or year sampled. The largest percent variance amongst stream or year factors (main and interactions) was at least three times greater than the corresponding method related percent variances. The results of this study suggest that these four bioassessment methods are interchangeable within the context of large geographic scales or for the detection of major impacts. In cases where impacts to the benthic community are subtle, protocols should include one or more of discrete habitat sampling, replication, and lower taxonomic resolution. The data and findings here may help agencies integrate different sampling protocols into their biomonitoring and assessment programs.

This paper describes findings of a research inquiry into the lived experience of homelessness in Peel, a suburban region located in the Greater Toronto Area in Ontario, Canada. It is based on the data from a collaborative project undertaken by members of the Faculties of Health and Education of York University with two local community organizations. The dominant theme of the narratives was that suburban homelessness is similar to being engulfed in a grotto of poverty, isolated from the rest of the community and invisible to it. Once entrapped in the grotto, it is almost impossible to escape from it. There were four sub-themes: (a) falling into the grotto, (b) living/struggling in the grotto, (c) envisioning escape routes from the grotto, and (d) beauty, community and hope in the grotto. Following a discussion of the findings, researchers describe strategies to address homelessness through promotion of social justice for all.

Surface-level ozone (O3) continues to be a significant health risk in the Greater Toronto Hamilton Area (GTHA) of Canada even though precursor emissions in the area have decreased significantly over the past two decades. In July 2015, Environment and Climate Change Canada (ECCC) led an intensive field study coincident with Toronto hosting the 2015 Pan American Games. During the field study, the daily 1-h maximum O3 standard (80 ppbv) was exceeded twice at a measurement site in North Toronto, once on July 12 and again on July 28. In this study, ECCC’s 2.5-km configuration of the Global Environmental Multi-scale (GEM) meteorological model was combined with the Modelling Air-quality and CHemistry (MACH) on-line atmospheric chemistry model and the Town Energy Balance (TEB) urban surface parameterization to create a new urban air quality modelling system. In general, the model results showed that the nested 2.5-km grid-spaced urban air quality model performed better in statistical scores compared to the piloting 10-km grid-spaced GEM-MACH model without TEB. Model analyses were performed with GEM-MACH-TEB for the two exceedance periods. The local meteorology for both cases consisted of light winds with the highest O3 predictions situated along lake-breeze fronts. For the July 28 case, O3 production sensitivity analysis along the trajectory of the lake-breeze circulation showed that the region of most efficient O3 production occurred in the updraft region of the lake-breeze front, as the precursors to O3 formation underwent vertical mixing. In this updraft region, the ozone production switches from volatile organic compound (VOC)-sensitive to NOx-sensitive, and the local net O3 production rate reaches a maximum. This transition in the chemical regime is a previously unidentified factor for why O3 surface-level mixing ratios maximize along the lake-breeze front. For the July 12 case, differences between the model and observed Lake Ontario water temperature and the strength of lake-breeze opposing wind flow play a role in differences in the timing of the lake-breeze, which impacts the predicted location of the O3 maximum north of Toronto.

Abstract. In Canada, risk of flooding due to heavy rainfall has risen in recent decades; the most notable recent examples include the July 2013 storm in the Greater Toronto region and the May 2017 flood of the Toronto Islands. We investigate nonstationarity and trends in the short-duration precipitation extremes in selected urbanized locations in Southern Ontario, Canada, and evaluate the potential of nonstationary intensity–duration–frequency (IDF) curves, which form an input to civil infrastructural design. Despite apparent signals of nonstationarity in precipitation extremes in all locations, the stationary vs. nonstationary models do not exhibit any significant differences in the design storm intensity, especially for short recurrence intervals (up to 10 years). The signatures of nonstationarity in rainfall extremes do not necessarily imply the use of nonstationary IDFs for design considerations. When comparing the proposed IDFs with current design standards, for return periods (10 years or less) typical for urban drainage design, current design standards require an update of up to 7 %, whereas for longer recurrence intervals (50–100 years), ideal for critical civil infrastructural design, updates ranging between ∼ 2 and 44 % are suggested. We further emphasize that the above findings need re-evaluation in the light of climate change projections since the intensity and frequency of extreme precipitation are expected to intensify due to global warming.

Introduction: Understanding how homeless patients interact with healthcare systems can be challenging. The nature of the population is such that identifying and following these persons can be severely limited by data. Previous studies have used survey data which relies on self-reporting and selected samples such as those persons admitted to homeless shelters (Gray et al. 2011). Other studies have been able to leverage administrative data but only for selected local geographic areas (Somers et al. 2016, Tompkins et al 2003). It is possible that the current literature has not examined a large proportion of homeless persons and their healthcare use. This is concerning because this population can have higher associated medical costs and greater medical resource utilization especially with regards to psychiatric and emergency department (ED) resources (Tulloch et al. 2012, Forchuk et al, 2015). Methods: Administrative health data (2010 to 2017) is used to analyze ambulatory care records for homeless individuals in Ontario, Canada. Uniquely, we are able to use ED contacts as a way of identifying homeless migrations from region to region within Ontario. Using a network analysis we identify high impact ED nodes and discrete hospital networks where homeless patients congregate. We are also able to more fully characterize this population's demographics, health issues, and disposition from the ED. Results: We provide a more complete understanding of migration patterns for homeless individuals, across Ontario and their concomitant ED use and hospitalizations. The three most frequented regions in Ontario (n = 640,897) were Toronto Central (35.96%), Hamilton Niagara Halimand Brant (8.9%) and Champlain (7.84%). In subsequent visits, the majority of patients presented to different EDs, however a subgroup who always presented to the same site was present. Over the 7 year period, migration between visits occurred most often between urban areas, and increased as a whole. Conclusion: The results of the study allow for the enhancement care coordination for vulnerable populations and enhance the availability and delivery of services for sub-groups of homelessness whose care needs may differ based on migration patterns. Services can be coordinated between jurisdictions for homeless individuals, and appropriate referrals can be made across the health care system. Further evidence is provided for a novel method of mapping migration among the homeless and its associations and effects on ED use.

Abstract. Tropospheric NO2 vertical column densities were retrieved for the first time in Toronto, Canada using three methods of differing spatial scales. Remotely-sensed NO2 vertical column densities, retrieved from multi-axis differential optical absorption spectroscopy and satellite remote sensing, were evaluated by comparison with in situ vertical column densities derived using a pair of chemiluminescence monitors situated 0.01 and 0.5 km above ground level. The chemiluminescence measurements were corrected for the influence of NOz, which reduced the NO2 concentrations at 0.01 and 0.5 km by 8 ± 1% and 12 ± 1%, respectively. The average absolute decrease in the chemiluminescence NO2 measurement as a result of this correction was less than 1 ppb. Good correlation was observed between the remotely sensed and in situ NO2 vertical column densities (Pearson R ranging from 0.68 to 0.79), but the in situ vertical column densities were 27% to 55% greater than the remotely-sensed columns. These results indicate that NO2 horizontal heterogeneity strongly impacted the magnitude of the remotely-sensed columns. The in situ columns reflected an urban environment with major traffic sources, while the remotely-sensed NO2 vertical column densities were representative of the region, which included spatial heterogeneity introduced by residential neighbourhoods and Lake Ontario. Despite the difference in absolute values, the reasonable correlation between the vertical column densities determined by three distinct methods increased confidence in the validity of the values provided by each of the methods.

Abstract. Tropospheric NO2 vertical column densities have been retrieved and compared for the first time in Toronto, Canada, using three methods of differing spatial scales. Remotely sensed NO2 vertical column densities, retrieved from multi-axis differential optical absorption spectroscopy and satellite remote sensing, were evaluated by comparison with in situ vertical column densities estimated using a pair of chemiluminescence monitors situated 0.01 and 0.5 km a.g.l. (above ground level). The chemiluminescence measurements were corrected for the influence of NOz, which reduced the NO2 concentrations at 0.01 and 0.5 km by an average of 8 ± 1% and 12 ± 1%, respectively. The average absolute decrease in the chemiluminescence NO2 measurement as a result of this correction was less than 1 ppb. The monthly averaged ratio of the NO2 concentration at 0.5 to 0.01 km varied seasonally, and exhibited a negative linear dependence on the monthly average temperature, with Pearson's R = 0.83. During the coldest month, February, this ratio was 0.52 ± 0.04, while during the warmest month, July, this ratio was 0.34 ± 0.04, illustrating that NO2 is not well mixed within 0.5 km above ground level. Good correlation was observed between the remotely sensed and in situ NO2 vertical column densities (Pearson's R value ranging from 0.72 to 0.81), but the in situ vertical column densities were 52 to 58% greater than the remotely sensed columns. These results indicate that NO2 horizontal heterogeneity strongly impacted the magnitude of the remotely sensed columns. The in situ columns reflected an urban environment with major traffic sources, while the remotely sensed NO2 vertical column densities were representative of the region, which included spatial heterogeneity introduced by residential neighbourhoods and Lake Ontario. Despite the difference in absolute values, the reasonable correlation between the vertical column densities determined by three distinct methods increased confidence in the validity of the values provided by each measurement technique.

Background: The global prevalence of hypertension in children and adolescents has increased over the past 2 decades and is the strongest predictor of adult hypertension. South Asians have an increased prevalence of metabolic syndrome associated risk factors including abdominal obesity, diabetes, and hypertension. All these factors contribute to their increased cardiovascular disease burden. Accurate and early identification of hypertension in South Asian children is a necessary aspect of cardiovascular disease prevention. Ambulatory blood pressure monitoring (ABPM) is considered the gold-standard for pediatric blood pressure (BP) measurement. However, its utilization is limited due to the lack of validated normative reference data in diverse, multiethnic pediatric populations. Objective: The primary objective is to establish normative height-sex and age-sex-specific reference values for 24-h ABPM measurements among South Asian children and adolescents (aged 5-17 years) in Ontario and British Columbia, Canada. Secondary objectives are to evaluate differences in ABPM measurements by body mass index classification, to compare our normative data against pre-existing data from German and Hong Kong cohorts, and to evaluate relationships between habitual movement behaviors, diet quality, and ABPM measurements. Design: Cross-sectional study, quasi-representative sample. Setting: Participants will be recruited from schools, community centers, and places of worship in Southern Ontario (Greater Toronto and Hamilton area, including the Peel Region) and Greater Vancouver, British Columbia. Participants: We aim to recruit 2113 nonoverweight children (aged 5-17 years) for the primary objective. We aim to recruit an additional 633 overweight or obese children to address the secondary objectives. Measurements: Ambulatory BP monitoring measurements will be obtained using Spacelabs 90217 ABPM devices, which are validated for pediatric use. The ActiGraph GT3X-BT accelerometer, which has also been validated for pediatric use, will be used to obtain movement behavior data. Methods: Following recruitment, eligible children will be fitted with 24-h ABPM and physical activity monitors. Body anthropometrics and questionnaire data regarding medical and family history, medications, diet, physical activity, and substance use will be collected. Ambulatory BP monitoring data will be used to develop height-sex- and age-sex-specific normative reference values for South Asian children. Secondary objectives include evaluating differences in ABPM measures between normal weight, overweight and obese children; and comparing our South Asian ABPM data to existing German and Hong Kong data. We will also use compositional data analysis to evaluate associations between a child’s habitual movement behaviors and ABPM measures. Limitations: Bloodwork will not be performed to facilitate recruitment. A non-South Asian comparator cohort will not be included due to feasibility concerns. Using a convenience sampling approach introduces the potential for selection bias. Conclusions: Ambulatory BP monitoring is a valuable tool for the identification and follow-up of pediatric hypertension and overcomes many of the limitations of office-based BP measurement. The development of normative ABPM data specific to South Asian children will increase the accuracy of BP measurement and hypertension identification in this at-risk population, providing an additional strategy for primary prevention of cardiovascular disease.

Abstract. Benzene and polycyclic aromatic hydrocarbons (PAHs) are toxic air pollutants that have long been associated with motor vehicle emissions, though the importance of such emissions has never been quantified over an extended domain using a chemical transport model. Herein we present the first application of such a model (GEM-MACH-PAH) to examine the contribution of motor vehicles to benzene and PAHs in ambient air. We have applied the model over a region that is centred on Toronto, Canada, and includes much of southern Ontario and the northeastern United States. The resolution (2.5 km) was the highest ever employed by a model for these compounds in North America, and the model domain was the largest at this resolution in the world to date. Using paired model simulations that were run with vehicle emissions turned on and off (while all other emissions were left on), we estimated the absolute and relative contributions of motor vehicles to ambient pollutant concentrations. Our results provide estimates of motor vehicle contributions that are realistic as a result of the inclusion of atmospheric processing, whereas assessing changes in benzene and PAH emissions alone would neglect effects caused by shifts in atmospheric oxidation and particle–gas partitioning. A secondary benefit of our scenario approach is in its utility in representing a fleet of zero-emission vehicles (ZEVs), whose adoption is being encouraged in a variety of jurisdictions. Our simulations predicted domain-average on-road vehicle contributions to benzene and PAH concentrations of 4 %–21 % and 14 %–24 % in the spring–summer and fall–winter periods, respectively, depending on the aromatic compound. Contributions to PAH concentrations up to 50 % were predicted for the Greater Toronto Area, and the domain maximum was simulated to be 91 %. Such contributions are substantially higher than those reported at the national level in Canadian emissions inventories, and they also differ from inventory estimates at the subnational scale in the US. Our model has been run at a finer spatial scale than reported in those inventories, and furthermore includes physico-chemical processing that alters pollutant concentrations after their release. The removal of on-road vehicle emissions generally led to decreases in benzene and PAH concentrations during both periods that were studied, though atmospheric processing (such as chemical reactions and changes to particle–gas partitioning) contributed to non-linear behaviour at some locations or times of year. Such results demonstrate the added value associated with regional air quality modelling relative to examinations of emissions inventories alone. We also found that removing on-road vehicle emissions reduced spring–summertime surface O3 volume mixing ratios and fall–wintertime PM10 concentrations each by ∼10 % in the model domain, providing further air quality benefits. Toxic equivalents contributed by vehicle emissions of PAHs were found to be substantial (20 %–60 % depending on location), and this finding is particularly relevant to the study of public health in the urban areas of our model domain where human population, ambient concentrations, and traffic volumes tend to be high.

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.

Off-peak-hour delivery (OPHD) has the potential to reduce congestion in busy urban areas and at the same time improve the efficiency of logistics providers, shippers, and receivers. There has been growing interest in OPHD in the Greater Toronto and Hamilton Area (GTHA), an important freight hub in Canada. The Government of Ontario is considering permanently relaxing noise by-laws to promote OPHD throughout the province. The purpose of this study is to provide quantitative assessments of the impacts of region-wide adoption of OPHD for the GTHA. A recently developed commercial vehicle (CV) model for the GTHA is presented in the paper. Various OPHD scenarios have been tested with the CV model. The impacts of induced passenger demand have also been demonstrated. Modeling outcomes indicate that OPHD could result in 5,530 vehicle-hours saved in a day after induced demand is accounted for. Light truck carriers would benefit the most by shifting to off-peak hours and prioritizing Toronto and Peel Region customers would yield the highest travel time savings during the off-peak hours.

Abstract Background The spread of carbapenemase-producing Enterobacterales (CPE) is global threat. Numerous outbreaks of CPE have been reported during the COVID-19 pandemic. We describe the impact of of the SARS-CoV-2 pandemic on the emergence of CPE in south-central Ontario, Canada. Incidence of clinical isolates of CPE and isolates with different CPE genes in Toronto/Peel region, 2017–2021. The upper panel shows the incidence of patients with clinical isolates of CPE by year and quarter from q4 2007 to q1 2022. The lower panel shows the incidence of patients with clinical isolates with different carbapenemase genes by fiscal year during the same period. Methods TIBDN has performed population-based surveillance for CPE in Toronto/Peel region (pop 4.5M) from first identified isolate in 2007. All laboratories test/refer all carbapenem non-susceptible Enterobacterial isolates for identification of CPE. Hospital charts are reviewed and patients/physicians interviewed. Population data are obtained from Statistics Canada. Results From 10/2007 to 3/31/2022, 1367 persons colonized or infected with CPE were identified. Their median age was 68.7yrs (IQR 54–78yrs); 761 (56%) were male. 772 (56%) were colonized when first identified; 115 (8.4%) were bacteremic at identification or subsequently developed bacteremia. The most common organisms were E. coli (651, 48%), K. pneumoniae (436, 32%), Enterobacter spp. (146, 11%), Citrobacter spp (62, 5%); the most common genes were NDM±OXA-48 (722, 53%), OXA-48-like (341, 25%), KPC (225, 16%), VIM (44, 3%). The incidence of CPE infections increased steadily until 3/2020 then declined by 61% and remained stable until 3/2022 (Figure, upper panel). The decline was greater for E. coli (56% decrease), K. pneumoniae (62%) than for Enterobacter spp. (30%) and other species (19%). It occurred in all genes in 2020; however, KPC containing organisms increased again in 2021 (Figure, lower panel). Conclusion The advent of the COVID-19 pandemic was associated with an immediate, substantial decline in the incidence of patients with CPE in our population area. This decline occurred in both isolates with genes usually occurring in cases imported from other countries, and in those usually occurring in cases associated with transmission within Canadian hospitals. Decreased travel and enhanced infection prevention and control in hospitals may both have contributed to reductions in CPE during the pandemic. Disclosures All Authors: No reported disclosures.