Theoretical framework/contextual literature:
There is no specific definition of sustainability and surely no standard definition for how it is applied to transportation. A good working definition of sustainability as it applies to cities was written by Brundtland commission of the United Nation in 1987: “sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs”. Achieving sustainability should be with joy and beauty, but at the same time it is important to realize the scientific fact of the current approach of transportation and its impact on the system.(tumlin, 2012)
Cities are not for building or vehicles it is for the people, this idea should be well considered while designing for the human needs, the aim is to help the movement of people not the vehicles. An ideal city for “penaloso” is where the pedestrian have enough space to move and interact with other.(cox, 2010)
Transportation is an exploitation tool that cities use to help fulfill their big goals, even that engineers focus on the efficient movement of people and goods, transportation is a part of all aspect of life in a city, these aspects are:
1- Economic development.
2- Quality of life.
3- Social equity.
4- Public health.
5- Ecological sustainability.
There is a relationship between transportation and environmental sustainability, petroleum is one of these factors, for example “in the united states about two-third of petroleum consumption is for transport. Along side with petroleum is gasoline and diesel where they are used for heavy cars, the replacement of the gasoline is not an easy thing to do, and at the same time there is lots of impact of using these none renewable sources such as:
1- Air pollution.
2- Water pollution.
3- Stormwater runoff.
4- Greenhouse gases.
There are 3 things that must be change to achieve sustainability in transportation. First, reduce the need for traveling and the overall distance. Second, changing the travel mode, this means change from driving to walking or cycling for the short journey and using public transportation for longer one. A research in London discovered that a travel for 1.7 mile by cycling will take 20 minutes, but it will take 30 minutes by car or public transportation. Third, to make vehicles that emit fewer.
To reduce travel, urban areas should be designed and planned to mix uses for each single area with a link between places, these links can reduce the need of a car.
A sustainable transport system meets the need of the city. Countries can achieve the goal in a clever way by offer a space for bicycle in the public transport, where people can have a multi-journey using buses and bicycles. Changing to a cleaner energy is the goal for most of the countries, to use a transport with new technology. For example, in USA they use higher fuel efficiency for cars, it is also called low-emission vehicles. These low or zero emission vehicles can affect the issue of air pollution.
The best way to achieve sustainability is to make sure that every urban area is designed in a way where residential, workplace, retail and social space can be reached in an easy way by walking, cycling or a good quality public transportation, by this way the carbon emission will be less.
There is a relationship between the urban density and the transportation, for example the variety of parking. The BioRegional studies shows that switching from petrol cars to use a car club with electric vehicles is an effective way to reduce the carbon emission. The car club can satisfy the need of 12 people rather than using a private car. The expansion of public transport can be affected by the density, people who live in easy walking area are using the services in more economically sustainable, city center in the other hand where there is a much higher density a mix use can be more effective, for example, shops in the ground floor and offices in the first floor. (Ritchie and Thomas, 2013)
Issues in sustainable transportation (range of issues):
Transportation has an impact on the sustainability in main three ways:
• Economic: traffic jam, accident damage, cost of the facilities and the consumer cost.
• Social: inequity of impact, human health impact, community interaction, community livability and aesthetic.
• Environmental: air and water pollution, habitat loss, hydrological impacts and exhaustion of non-renewable sources.
These problems and impact led to new strategies some of them have been introduced as an option and some of them indicate that a combination of strategies can get a more beneficial impact. (Litman, T. and Burwell, 2006)
The vision of sustainable city:
Today’s sustainable cities doesn’t look as before, a new vision start to appear. The aim of the sustainable city is to design a city that is considering the human health, human body and its needs, one of these things that help the human body is “walking”, a city should encourage the people to walk 10",000 steps a day, and should suits people of all ages with lots of joy as it is also good for our social life.
One of the best spaces for walking is the enclosed space, these spaces should be organized with a good relationship with the street to enhance the walkability. Sidewalk should be also taken in consideration with the use of different material to be recognize. The effect of human behavior is also important, for example putting a window that is facing the street can also encourage the walkability. As for the different climate where it is not easy to walk because of the sun and wind, a shelter for the sun and wind can help to reduce this kind of problems, not only shelter, trees can also play the rule of shelter. With a good maintenance can give the feeling of carness that create a relationship with place and enhance walking.
The second sustainable transportation is cycling, cycling can provide lots of benefits for the health and social life which is similar to walking. Cycling is the most energy efficient type of transportation and a it suits people of all ages. Increasing the number of cyclists is very challenging but it is not impossible at the same time, in order to increase the cyclist, it is very important to concentrate on people that do not ride. Bike should be affordable to everyone, but the main problem that face people is not having a bike but is where to keep it and store it, one of the solutions is to have a bike garage or at least bike parking, these parking can encourage people that have a bike to use it for their daily use. Moreover, bike rental is also considered as solution to encourage people to use a bike, but at the same time the distance play a rule on that, a bike can be use for the whole journey and at the same time it can be used as a part of the journey if the distance is far, after using a bike another type of transportation can be used like buses and metro. The author believe that the increasing of cyclist number is also increase the safety, but the safety needs more than that, it can be improved by adopting a bicycle line that should be done in a good quality with a physical barrier to separate the vehicle road and the bicycle road.(tumlin, 2012)
Public transportation should be preferable over private transportation as this type of service is affordable for the entire population and at the same time it is cheaper, using a bus is a beneficial way especially for the environment and social and at the same time it has some disadvantage like the speed of the bus. A new system appear as a development of the bus which is the Bus Rapid Transit system, this type of buses have its own line and a special station for fast boarding, the system is high quality and more efficient and comfortable, other advantage of the system is that the cost of the infrastructure is low, it take less planning time, fast construction timing, more flexible and high speed system. (cox, 2010)
Transportation and land-use:
A better transportation plan means a better land-use plan, and to achieve that there are some steps that should be followed:
Mostly the main aim of planning the street is to decrease the traffic percentage which is the main problem that face people all around the world, and for that a new path can be created with more walking distance is considered as solution, furthermore creating a mix use area with all daily need within walking area, as for the retail it is preferable to be in a clear visible area that is near to a main road and at the same time avoid putting a retail center on a street that is prone to traffic congestion. The location of the schools is also very important, school should be located in a walkable area that is in the middle of a residential area with a bicycle line.(tumlin, 2012)
There is a relationship between traveling and behavior of people, people are affected of their culture and beliefs which is not an easy thing to change it, in some countries people believe that every member of the family with a driving license should have a car and sharing the public transportation with worker is embarrassing. Long distance is also affecting, narrow alleys required a bike or walking to reach the specific distance while a very far city required a motor vehicle to reach in shorter time. another factor is the gender and age, for example a 9 years old boy can’t use his private bike to go to a different city by his own.(Hull, 2011).