Intro

Land use and town planning, the central aspects of eliminating GHG

The land use and town planning are the tools we use to shape our living environments and their structure. Therefore, they determine in large part our communities’ energy consumption patterns and they have an impact on many factors of greenhouse gas emissions (GHG), in particular:

  • Building and maintaining facilities (type, size and choice of material);
  • Transporting people and goods;
  • Maintaining or losing natural spaces;
  • Heating and air-conditioning of buildings.

The land use of a community sets characteristics for at least one or two generations. Highways, museums and neighborhoods are built to last for several decades. Their location and choice of material, for example, may have impacts that lasts for their entire life cycle. In addition to reducing the energy costs of community facilities directly, urban development has an effect on the lifestyle and therefore helps reduce GHG emissions at source.

Climate change can be dealt with in many ways. Part of the solution lies in technical innovations and everyday actions. However, the best way to overcome together the barriers we cannot overcome individually is to bring about significant changes in the way we plan urban development, in order to align it with the challenges we now face. This conclusion is reached by many, both locally (Jean Charest - in French) and in the rest of the world (Carfree France – in French).

The vicious circle of automobile dependency [1]

The arrival of the automobile disrupted the cities’ urban development. Dense cities, that were based on public transit and active transportation and where people had easy access to various services, proceeded to quickly spread out. The era of the tramway had already caused cities to expand beyond what nonmotorized travel modes previously allowed; but contrary to the car that would eventually replace it, the tramway helped establish relatively compact urban forms where active transportation kept its importance.

After the Second World War, with the car becoming popular, North America underwent a massive urbanization phase which happened to be based on what we now call sprawl, creating suburban areas located ever further from downtown. In this new context where density and accessibility were no longer priorities, zoning regulations were now oriented towards a strict separation of land uses in order to limit the inconveniences of certain activities. The urban structure changed and traveling distances increased. In the period between 1971 and 2006, where the population of the Quebec City census metropolitan area increased by 62%, the built area increased by 261% [2]. These planning choices ensured that the car became an essential part of most people’s transportation needs.

Vicious circle of automobile dependence – Source: Vivre en Ville, inspired by Raad, 1993.

This now results in chronic road congestion problems which governments usually try to solve by increasing road capacity. Unfortunately, this solution is short-lived and has a negative impact on the urban structure. In fact, the new roads attract new residential or commercial developments and generate new trips that will take up 50 to 90% [3] of the additional road capacity. This phenomenon, which is known as induced traffic, is integral in reinforcing the vicious circle of automobile dependency where the new roads develop their own congestion problems which will temporarily be solved by the same short-term solution.

Public transport, GHG emissions and oil dependency

Over the last decades, the urban sprawl has increased travel distances and motorized travel, and has created a growing automobile dependency that caused a drastic increase of GHG emissions.

Proof of this is the increase of the car to population ratio. Between 2000 and 2009 in Quebec, the number of motor vehicles rose by 24% while population growth was only 6.1% [4]. The more vehicles on the road, the more total distance travelled increases. From 1990 to 2007, total distance travelled by motor vehicles in Quebec went from 50 to 71 billion kilometers [5].

During the same period between 1990 and 2007, while almost all of Quebec’s various industrial activities managed to reduce their GHG emissions, the road transportation industry increased them by 37% [6]. Today, the transportation industry is accountable for 43% of the total amount of GHG emissions in the province, of which close to 80% is caused by road transportation of people and goods. To reach the Kyoto protocol objectives (and Quebec’s of 20% below 1990 levels by 2020) is to imperatively act on this sector.

Traffic on highway I-80, in Berkeley, USA – Source: Wikipedia.org / Minesweeper

The improvements in the energy efficiency of vehicles appear insufficient to reverse the trend. Firstly because of the growing share of light trucks and other large vehicles in the car fleet [7], and secondly because the gains from better energy perfomance are offset by a faster increase in travelled distances.

A costly dependency

The car-based spatial organization of cities has various negative impacts, among which are:

  • In the Montreal region alone, congestion results in annual costs of 1.4 billion dollars [8].
  • Urban sprawl and car-oriented infrastructure causes wastage of huge tracts of land.
  • Asphalt-, concrete- and tar-made roads, bridges and parking lots have low albedos, which makes them absorb heat, creating urban heat islands and their associated negative health impacts.
  • The resulting impervious surfaces eliminate the natural processes of water retention and filtration.
  • Urban sprawl increases the costs of construction and maintenance of public networks and facilities, as well as energy consumption at the neighborhood level.
  • The highways and expressways block and restrict walking and biking trips, creating no man’s land where walking is, if not dangerous, at least unpractical and uncomfortable.
  • Increasing automobile traffic hinders social interaction and contributes to breaking up the social structure.

Reversing the trend: the logic of a compact city

When the urban structure adapts itself to the car, it becomes less and less compatible with other means of transportation that, in order to be efficient, need density.

The contribution of planning in improving the carbon footprint of our communities brings different benefits and takes into account the particular context of every living environment.

Since the 80s, the Smart Growth movement in North America has suggested a planning approach that focuses on the idea of a compact city. More recently, many cities provide planning examples that successfully implement the elements previously mentioned. This is the case, for example, for Stockholm in Sweden, and Portland in Oregon. There are also examples of model neighborhoods that are entirely built in accordance with the principles of the compact city. These ecodistricts, usually pilot studies that allow developers, builders and planners to develop skills and spread expertise, can lead to exemplary neighborhoods that become part of their city and offer an ideal living environment to their inhabitants. Well-known examples are the Vauban neighborhood, in Freiburg-im-Breisgau in Germany, and Hammarby, a neighborhood in Stockholm, Sweden.

There is no magic formula for the sustainable development of communities. It is fundamental that a large variety of elements and opinions be considered. That way, the various issues related to adequate land use planning can hopefully be dealt with appropriately.

Notes

  1. [1] Vivre en Ville, 2009. Le développement urbain viable au coeur de la stratégie québécoise de réduction des émissions de GES. (PDF – in French)
  2. [2] Communauté métropolitaine de Québec, 2006. État de situation préparé dans le cadre de l’élaboration du schéma métropolitain d’aménagement et de développement (SMAD) AND Statistics Canada, Population and dwelling counts, for Canada, census metropolitan areas, census agglomerations and census subdivisions (municipalities), 2006 and 2001 censuses
  3. [3] Victoria Transport Policy Institute, 2010. Rebound Effects : Implications for Transport Planning (TDM Encyclopedia)
  4. [4] SAAQ, Données et statistiques 2009 (PDF – in French) et ISQ, 2009. Le bilan démographique du Québec
  5. [5] Office of Energy Efficiency of Canada, 2008. 2008 Canadian Vehicule Survey Update Report
  6. [6] MDDEP, 2009, Inventaire québécois des émissions de GES en 2007. (PDF – in French)
  7. [7] Office of Energy Efficiency of Canada, 2009. Energy Efficiency Trends in Canada, 1990 to 2007.
  8. [8] Board of Trade of Metropolitan Montreal, 2010. Public Transit: At the Heart of Montreal’s Economic Development. (PDF)

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Efficient, well designed and well located buildings

Centre culture et environnement Frédéric Back in Quebec City, an example of sustainable building reconversion. Source: CCEFB

In Quebec, residential, commercial and institutional buildings’ operation and maintenance is responsible for a significant share of the GHG emissions: 10.3 billion tons CO2 equivalent in 2007, accounting for 12.5% of overall emissions. 41% of these emissions come from the residential sector, mainly due to the use of fossil fuels for heating[1]. The good news is that those emissions have been steadily declining since 1990, thanks to improvements in buildings’ energy efficiency and the transfer from fossil fuels to cleaner energy sources. Although gains from further improvements in energy efficiency are still possible, we now need to capitalize on the high potential offered by the communities’ development and patterns.

The efficiency of urban form

The current development pattern based mainly on single-family detached houses leads to enormous energy losses, as far as heating is concerned in particular. The type and characteristics of a housing unit can vastly impact its heating energy needs.

Average energy consumption for heating by housing unit category[2]

Housing unit category Consumption (kWh/yr) Floor space (m2) Consumption by m2 (kWh/yr/m2)
Single detached 24 903 138 181
Single attached 15 375 113 136
Apartment 10 634 90 118

2008 data collection for Quebec, Office of Energy Efficiency of Canada

In fact, heating a single-family detached house requires on average 2.3 times more energy than an apartment, and 1.6 times more than a single-family attached house. There are two main reasons that explain these variations:

  • Size: On average, a single-family detached house is 1.5 times the size of a typical apartment and 1.2 times the size of a single-family attached house.
  • Energy efficiency of the housing unit pattern: due to its shape and location, a single-family detached house is more vulnerable to the elements than a single-family attached house or an apartment. Indeed, the latter benefit from the protection and the heat from adjacent units. This explains why a single-family detached house requires 1.5 times more energy than a similarly-sized apartment and 1.3 times more than a single-family attached house.

These differences cause higher GHG emissions for single-family detached houses that rely on fossil fuels for heating (hydro-electricity is very common in Quebec and emits very little GHG). In this case, emissions of a single-detached house are 3.84 tons of CO2 equivalent/unit/yr. This number falls down to 2.87 tons/unit/yr in a single-attached house and an apartment only accounts for 2.45 tons/unit/yr.

Besides, units tend to be underused as they always get bigger while households slowly shrink. This results in unnecessary heating of mostly unoccupied rooms.

Lifecycle, materials and construction

Operations and maintenance are not the only aspects of a building accountable for GHG emissions. Indeed, when we look at the ecological footprint of a building, we must consider its whole liftecycle from design to operation and maintenance, and even the way it might be reused or recycled. Construction of buildings and infrastructure is responsible for about 20% of neighborhood energy consumption and greenhouse gas emissions over a 50-year assumed lifespan[3]. Buildings must be designed in order to capitalize on the characteristics of the site in which they will be set, considering for instance orientation, shade and insulation. This practice is called bioclimatic architecture, and it materializes through passive solar building design. Building materials choices (local when available, non-toxic, easily recyclable…) and construction wastes management must also be addressed. Taken all together these considerations can have an important impact on the GHG emissions of buildings.

Healthier and more comfortable buildings

Energy efficiency and GHG emissions are not the only factors to take into account: greater comfort through better building design, for example, is another benefit. Smartest use of available space, precise temperature control and healthy building materials are only a few of the improvements that fall into designing buildings according to stringent quality standards.

The building sector must take part in the development of sustainable communities. But these issues all have to be addressed in a global perspective. The improvements in energy efficiency have been considerable in the recent years. Even so, building type and location remain essential to an efficient strategy to lower GHG emissions.

Notes

  1. [1] Ministère du Développement durable, environnement et parcs (Québec), 2010. Québec 2009 inventory of greenhouse gas emissions and evolution since 1990. (in French)
  2. [2] Office of Energy Efficiency of Canada, Comprehensive Energy Use Database Tables – Residential Sector, Quebec.
  3. [3] Jonathan Norman et al., 2006, in Playbook for green buildings + neighborhoods – Construction impacts.

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Green, comfortable and affordable living environments

Trees are important assets for cities and other living environments, as they:

  • improve air quality;
  • are efficient windbreakers;
  • mitigate the heat island effect and generally lower summer local temperatures;
  • contribute to rainwater retention and filtration;
  • are sound absorbing;
  • capture CO2;
  • and of course, betters the overall living environment.

In Montpellier, urbanity and vegetation – Source: Vivre en Ville

For example, a thirty-year-old tree captures on average 9.4 kg of CO2 per year, which is to say that you’d need about 130 such trees to capture the 4500 kg of CO2 an average car emits by being driven 20,000 km in a year[1]. Moreover, planting trees and shrubs around buildings can help cut energy needs by 10 to 30%[2], thanks to their windbreaking (in winter) and cooling (in summer) properties.

The cooling properties of trees are due to the way they grow, which involves the absorption and evaporation of water in a process known as evapotranspiration. A mature tree can in this way release a few hundred liters of water everyday. And since evaporating water requires energy, which is drawn from the surrounding heated air, the process results in a significantly lower-temperature microclimate. A large tree, which would release approximately 450 liters of water in any given day, would for example have a cooling power equivalent to 5 medium-sized air-conditioning units running 19 hours a day – and these would merely transfer heat outside of the building without “eliminating” it[3]. Moreover, air-conditioners also require power.

Fewer heat islands

One of the greatest benefits derived from these characteristics is the mitigation of the heat island effect. A green park and a sparsely vegetated public space located merely a couple hundred meters apart can experience a dramatic temperature difference of 15 °C or even more.

Huge differences in temperature are due to the absence of vegetation – Source: CRE Laval, 2006, Étude des biotopes urbains et périurbains de la CMM

This is again due to the evapotranspiration process, but also to the better albedo (or solar radiation reflecting capacity) of the foliage and grass compared to that of asphalted surfaces.

Soils as natural rainwater processing plants

With the proliferation of impervious surfaces like asphalted roads and parking lots, rainwater (and the pollutants it captures from these) are quickly drained to the watercourse network, resulting in polluted runoff – or what is called nonpoint source pollution, a very difficult problem to tackle. In fact, vehicle infrastructure is responsible for 80% of the overall surface runoff [4]. Conversely, permeable soils have many advantages. Firstly, they retain water for a longer time, allowing part of it to naturally evaporate (and thus lowering the ambient temperature). Secondly, they naturally filter and treat water, allowing it to continue through its natural cycle. Finally, the unhindered natural percolation process regulates the watercourses’ flow rates, which helps reduce bank erosion caused by flash floods.

Natural rainwater management system in Malmö – Source: Vivre en Ville

Stakeholders in the greening effort

Soil sealing and the presence of trees are major issues that should concern individuals and communities alike. Indeed landowning citizens have an important role, as they are able to act directly and locally. At a higher level, municipalities have the power to switch their stormwater systems to an open-channel flow configuration (which actually costs less to maintain once it’s built), and to require minimum tree cover ratios for various areas of the city.

Notes

  1. [1] G. Lessard et E. Boulfroy, 2008. Les rôles de l’arbre en ville (PDF in French).
  2. [2] McPherson, Nowak et al., et Ontario Ministry of Housing dans Micheal Hough. 1995. Cities and Natural Process.
  3. [3] Michael Hough, 1995. Cities and Natural Process.
  4. [4] J. Heaney, R. Pitt et R. Field, 1999. Innovative Urban Wet-Weather Flow Management Systems.

Useful reading

Tree Canada (Web site)

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Accessible, fair and vibrant communities

An accessible city offers its inhabitants access to its different components and activities no matter what is their social position or how much they earn. Equity is the core aspect of accessibility. For over 50 years, cities have evolved around the concept of car mobility, mostly leaving the other transportation modes out of the equation – including walking, the natural way of moving around. Separation distances between land uses naturally leads the commuter to get into his car, and neighborhood and road network configurations even more so. In addition to the high costs it entails for individuals and society alike, such a system penalizes a significant proportion of the population. Wether by choice, because of physical limitations or old age, or for financial reasons, many people don’t have easy access to a car.

Human-centered planning and design

Accessibility for all can be achieved in cities by thinking their planning in terms of their main component, which is the human being, and its primary travel mode, which is walking. It thus naturally follows that measures fostering active transportation also have positive impacts on accessibility.

Here are some of the important aspects that need to be taken into account when considering the issue of accessibility in our cities:

  • Permeability, which shortens pedestrian routes;
  • Safety and perception of safety;
  • Equitable sharing of public space, including streets, between users;
  • Visual, olfactory and accoustic comfort for pedestrians;
  • Proximity to the various activities (housing, shops and services, recreation and parks).

When all these elements come together in a coherent fashion, the car no longer comes to mind as being indispensable. In such an environment, it becomes possible for a majority of the population to easily meet its daily needs locally by taking advantage of direct routes in safe environments where pedestrians comfortably share the street network with other users.

In the Vauban neighborhood in Germany, mix of uses and various choices for transportation are key elements of accessibility – Source: Vivre en Ville

Of course, the intended result here isn’t to force the entire population out of their car and on the sidewalks, but rather to ensure that as many people as possible have various transportation options, and that walking becomes a efficient way of moving around most of the time. Besides, such pedestrian-friendly environments are usually quite compatible with other alternatives to solo car driving, without causing major obstacles to car drivers. And these other alternatives are a crucial part of the plan: beyond a certain distance, say 1 to 2 km, walking becomes increasingly difficult, which hinders access to areas and activities of the community.

For longer trips, cycling and public transit take over

Biking and public transit are important vectors of accessibility for those greater distances that walking cannot address. The issue is both local (at street and neighborhood levels) and regional (at city or metropolitan levels). Indeed, a proper strategy lies with the implementation of relevant infrastructure which also displays pedestrian-friendly characteristics, among which are the following:

  • Well located and distributed mass transit stops and stations;
  • Bikeways;
  • Secure bike parking.

But in order to turn biking and public transit into credible transportation alternatives and thus increase the accessibility level of a community, the two travel modes must be part of a systematic planning strategy that goes beyond the neighborhood scale. It is thus important to provide a complete and coherent public transit and bikeways network that gives quick and easy travel options to as great a number of people as possible.

Laneways fit for active transportation in Vauban – Source: Vivre en Ville

It should also be noted that better accessibility leads to increased commercial activity and social interaction, while at the same time reducing GHG emissions thanks to fewer car trips.

Simply put, accessibility is key in understanding and addressing a number of problems – like those related with the issues of density, mix of uses, active and public transportation – with the efficiency of an integrated approach.

Useful readings

  • Claude Villeneuve, Yan Kestens, Rémy Barbonne, Jeanne Robin & Céline Bourel, 2006. “Exploring Alternatives to Sprawl in the Quebec Metropolitan Area”, In The International Faces of Urban Sprawl.
  • Gehl Architects (Web site)
  • Luca Bertolini, Frank le Clercq & L. Kapoen, 2005. “Sustainable Accessibility: A Conceptual Framework to Integrate Transport and Land Use Plan-making. Two Test-applications in the Netherlands and a Reflection on the Way Forward”. Transport Policy, vol. 12.
  • Victoria Transport Policy Institute, 2009. Transportation Affordability: Evaluation and Improvement Strategies. (PDF)

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“Zero emissions” trips with many underlying benefits

As the natural way of moving around, walking is by far the main type of active transport. Add the bicycle to that, and you get two cheap and efficient means of transportation. Since they tap on human energy alone, there is obviously no GHG emissions involved. And there isn’t much tradeoff in using them either, since they actually are excellent alternatives to other transportation modes: indeed, almost half of all daily commutes are less than 3 km long (a 30 minutes walk or a 12 minutes bike ride), and 25% of them are 1,5 km or less (a 15 minutes walk) [1]. It is also worth noting that city traffic conditions make the average speed a car can reach on par, or even less, to that of a typical cyclist. Despite this, motorized transportation still is the prefered choice, even for short trips – in the greater Montreal area for example, 55% of trips of less than 1,6 km are motorized [2].

Walking and biking have individual and collective positive effects on various aspects of our lives. For one, they make an overwhelming economic case, first for the user, but also for society since the pressure on the road infrastructure – and thus the cost of its maintenance – is vastly reduced. But even if for some strange reason you should cast aside these arguments, nobody can justify ignoring the health-related ones.

Public health and active transportation

Of increasing concern are the health problems related to physical inactivity and car dependency, issues for which a widespread adoption of active transportation modes would be an important part of the solution. In Canada, overall inactivity-related health costs were valued at $5.3 billion in 2001, including $1.6 billion in direct costs for the health care system [3]. And it just so happens that public health experts now formally recognize the benefits of active commuting in preventing weight-related health problems.

  • Obesity prevalence decreases by 4.8% [4] for each km of walking per day;
  • In Canada, sedentary people make use of the health care system 38% more frequently than those considered physically active [5].

Using active transportation modes also alleviates road congestion, reduces air pollution and improves road safety. Again, social costs speak volumes:

  • Air pollution costs Quebec $1.3 billion every year, 97% of which is related to health problems [6];
  • As for road accidents, their cost is estimated at $3.9 billion per year [7].

Despite numerous benefits, walking and biking are frequently cast aside as viable transportation options, and the fact that they can’t always rely on a conducive environment doesn’t help.

Planning communities to promote active transportation

Urban form and the way streets and public spaces are planned impact individual transportation choices. Without the support of a safe and pleasant environment in which to bike or walk, active transportation cannot measure up to the feelings of comfort and convenience the car usually generates. A study by the Department of Transportation of the Washington State demonstrates that residents of neighborhoods lacking pedestrian amenities walk on average 3,2 times less than those living in more pedestrian-friendly ones.

Streets with poor amenities make it unpleasant to walk and risky to cross – Source: pedbikeimages.org / Dan Burden

When it comes to putting favorable conditions in place, communities have various options at their disposal:

  • Develop human-scale neighborhoods: narrow streets, closely-spaced intersections, building entrances directly accessible from the street, quality street furnitures, etc.;
  • Increase the mix of activities in order to offer a variety of goods and services within walking distance;
  • Set up traffic calming measures and improve safety and comfort for pedestrians and cyclists;
  • Put cycling infrastructure in place: bikeways, bike racks, etc. Incentives for companies to install showers, lockers and other amenities are good too.

Improved comfort and safety for pedestrians and cyclists are generally compatible, and in some cases even mutually reinforcing.

A pedestrian-friendly commercial street in Durham, New Hampshire – Source: pedbikeimages.org / Dan Burden

Indeed, a pedestrian-friendly environment is usually associated with lower vehicle speeds, which in turn allow cyclists to move along safely without the need for bikeways. In the same way, cycling infrastructure circumscribes the space the car occupies and thus tends to give pedestrians a more pleasant environment.

Laneways open to different modes of transportation in Vauban – Source: Vivre en Ville

Fair and active communities

In order to meet everyone’s needs, communities should always keep in mind the importance of active transportation in general and walking in particular, since everyone, including car drivers, becomes a pedestrian at some point. Questions that should thus be asked are: is the neighborhood or city offering goods and services accessible within walking or biking distance, or via public transit? Are comfort and safety conditions of the streets and public places conducive to the use of active transportation? Do pedestrians and cyclists have access to direct routes, and do they benefit from an environment planned and designed with their needs in mind? All these questions are integral to an active transportation planning strategy and should be asked, thought over and answered appropriately by the planners and designers of a community.

Notes

  1. [1] John Pucher & Lewis Dijkstra, 2003. “Promoting Safe Walking and Cycling to Improve Public Health: Lessons From the Netherlands and Germany”. American Journal of Public Health, vol. 93, no. 9.
  2. [2] Juan Torres & Paul Lewis, 2010. “Proximité et transport actf : le cas des déplacements entre l’école et la maison à Montréal et à Trois-Rivières”, Environnement urbain, vol. 4.
  3. [3] Peter T. Katzmarzyk and Ian Janssen, 2004. “The Economic Costs Associated With Physical Inactivity & Obesity in Canada: An Update”. Applied Physiology, Nutrition and Metabolism, vol. 29, no. 1.
  4. [4] Lawrence D. Frank, Martin A. Anderson & Thomas L. Schmid, 2004. “Obesity Relationships with Community Design, Physical Activity, and Time Spent in Cars”. American Journal of Preventive Medicine, vol. 27, no. 2.
  5. [5] N. Sari, 2009. “Physical Inactivity and its Impact on Healthcare Utilization”. Health Economics, vol. 18, no. 8.
  6. [6] Transport Canada, 2007. Evaluation of Total Cost of Air Pollution Due to Transportion in Canada.
  7. [7] Transport Canada, 2008. Estimates of the Full Cost of Transportion in Canada.

Useful reading

http://www.pedbikeinfo.org/

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