Conclusiones Parciales

Likewise, the quest to have clean local air is of great importance.

The data indicates that particulate matter and other toxins are in their highest concentrations along roadways and intersections than anywhere else in a typical city.

This indicates that transportation traffic in the city contributes as much or more significantly to air pollution than surrounding industry does; and these emissions are directly related to acute and chronic heart disease (Topalovic et al., 2012).

To arrest the growth of private automobile emissions we will have to offer other means of travel on equally excellent multi-destination transport networks. Linking walkable

Literature Review Page 74 mixed-use environments is a significant strategy and fundamental to a Transit-Oriented Region.

5. HEALTH

Over the past two decades, there has been a growing recognition that our contemporary urban environments adversely affect our health in new and apparently more intractable ways than in the past (Townshend & Lake, 2009).

Diabetes, obesity, cardio-vascular disease, air particulates causing respiratory problems, stress are all being linked to living an automobile-dependent lifestyle. Those living in automobile-dependent cities don’t walk as much as they ought to; they tend to eat more processed foods (high in fat, salt and sugar) as their time-budgets don’t allow the flexibility of growing food and preparing proper meals; they tend to experience undue stress sitting in traffic congestion after a long day in the office, also sitting down and being stressed with timelines; and likewise, the act of commuting by automobile places them directly in the particulate- and gas-rich exhaust of many thousands of vehicles.

The link between obesity and car dependence is that if the whole travel time budget is taken up by driving, little time for walking will be found. Building cities where walking is part of the travel-time budget is a major reason for creating less car-dependent cities (Newman & Kenworthy, 2006).

There are many academics working in this area of linking health outcomes to lifestyle with most finding that automobile-dependent lifestyles are not adding to our quality of life.

The list of citations here could be very long; relevant findings include these from Frank, Townshend, Edwards and Stokes.

From Frank:

Each additional hour spent in a car per day was associated with a 6%

increase in the likelihood of obesity. Conversely, each additional kilometer walked per day was associated with a 4.8% reduction in the likelihood of obesity (Frank et al., 2004).

Increasing walking to about 2 kilometers per day is roughly equivalent to the public health goal of at least 30 minutes of moderate activity. This goal may be achieved through a variety of policy options that include shorter-term incentives for walking for both utilitarian and recreational purposes, and longer-term changes in the

Literature Review Page 75 built environment, such as increased mixed use, density, and street connectivity that

make walking an attractive and viable option (Frank et al., 2004).

And to get there, Frank recommends:

To realistically increase the level of walking and biking, it will be essential to reintroduce development practices that make it easier to engage in such activities during the course of one’s daily activities. This may mean not only the introduction of the types of urban design features advocated by neo-traditionalists into developments located at a region’s periphery but also the retrofitting of existing urban areas. For example, the provision of non-motorized linkages between residential, commercial and employment areas reduces the time required for travel on foot while holding the time requirements for auto access constant. In accordance with microeconomic theory, this should render a relative increase in the utility of walking and biking versus driving and promote physical activity while reducing auto dependence (Frank & Engelke, 2001 p.215).

Townshend finds an interesting relationship:

An interesting relationship that seems evident from these studies relates to people who live in traditional mixed-use neighbourhoods. These are those neighbourhoods where local shops and services, school and employment opportunities are easily accessible within walking distance of people's home of a type prevalent in the UK up to the 1960s. Here, people tend to over-estimate the number of opportunities they have at their disposal for activity, contrastingly those in more recently developed neighbourhoods, designed around car use under-estimate opportunities. If use levels are linked to perception, as much as actual availability, then it appears that traditional mixed-use areas are doubly advantaged (Townshend

& Lake, 2009).

Individuals living in neighbourhoods with higher population density, greater access to public transport and a greater mix of land uses had significantly lower BMIs compared to groups living in neighbourhoods that did not display these characteristics; though the study found no correlation to measurements of connectivity (Townshend & Lake, 2009).

Edwards finds that transit access promotes walking to the extent that it may reduce the chances of obesity:

While no silver bullet, walking associated with public transit can have a substantial impact on obesity, costs, and well-being (Edwards, 2008).

Literature Review Page 76 Use of public transit is associated with more walking, by about 8.3 extra

minutes per day. This is not enough walking to halt the spread of obesity, but it could substantially reduce it (Edwards, 2008).

And Stokes reminds us that the layout of the streets, in grid or modified grids, rewards the walker with closer destinations and safer routes:

Mixed-use development also provides more local commercial options that do not require automobile trips. Grid street patterns lessen pedestrian distances and provide a safer walking environment (Stokes et al., 2008).