A new sustainable approach should be used to address the arising issues regarding to sustainability. The paper will discuss the role of landscape architecture in a city as a planning instrument for sustainable development and High Line, New York will be explored in detail about how by preserving and re-slung structure relics, abandoned industrial structures can be transformed into new green public parks that enhances the environmental sustainability of the New York city. Urban planning plays a critical role in maintaining the resilience and increasing the quality of life in cities.
Imagine a city with only conventional planning, in which it only deals with zoning, public facility, and transportation, not yet addresses Issues of sustainability and awareness of pollutions. The city will continue to consume energy in an endless manner, consuming water, fuel and furthermore the non-renewable construction materials like steel, concrete, stone, and timber. Without a carefully thought out sustainable approach, the resources will just go into landfills and pollute the river streams and air and can never be retrieved again.
This will deplete the natural resources and worsen the living environment for both human being and the ecosystem. This negative cycle could only have gone worse and worse. Instead, why tot approach planning in sustainable ways? Turning process into a cyclic one? Adopting the cradle-to-cradle methodology In planning, and develop the city Into where waste equals food, so every waste becomes the nutrient of another production cycle. One of the tactics could be re-using existing abandoned structure and redevelop It Into new sustainable landscape architecture.
Currently, approximately 1/3 of waste are produced from construction and demolition waste and “over 90% of non-energy minerals extracted In the UK are used for construction materials, yet every year some 70 million tones of construction and emulation materials and soil end up as waste, 13 million tones of which comprise material delivered to sites and thrown away unused (Archie 2011 ,up. 78). ” It Is clear that the inefficiency in construction industry is causing a huge waste problem, and the waste must be treated carefully to avoid pollution.
Wastes can be treated in many the most important step would be on site separation, which is making sure the waste could be up cycled and is durable to be used as construction material again, but it requires huge costs and skilled labors therefore it is usually not economically seeable. Unfortunately, in many cases, the constructions materials are in hybrid with other materials, resulting in the lost of its original properties, thus are not durable enough to be used as raw materials again. As the result, the present way of down cycling depletes the natural resources, and pollutes the soil and stream with landfill.
To change the cradle to grave cycle into a cradle-to-cradle life cycle for abandoned structures, landscape architecture is one of the instruments to implement this concept. Landscape architecture as a planning instrument allows the idea of ransoming relics into something green, which it could enhance the environmental sustainability of a city. Landscape architecture is not merely about “prettification of the city; it is about creating value of a place. It is about changing perception of the value(Hum, 2012)” of public space, and it reunites people in the city as a community where they appreciate the city and gain a sense of belonging.
It is necessary to make people aware of the public spaces they occupied, and realize that every aspects was designed to convey certain messages. Everything you see on the street apart from the alluding itself, belongs to the realm of landscape architecture; it is hugely responsible for the living quality of a city. In the case of re-using industrial relics to build new sustainable landscape in the city, it preserves the structure and the embodied energy within and allows the structure to gain a new identity and community value in a city. It could potentially become a driving force to drive the sustainable development in a city.
High Line, New York is a successful case of preserving and rehabilitating railroad relic and transforms it into a valuable green community space. Case Study: High line High Line is a 1. Km New York City linear park built on a 2. 33 km section off to be demolished former elevated New York Central Railroad. A massive former industrial abandoned structure after 1980, consisting of steel and concrete, which could be potentially hard to recycle and would generate a large cost for infrastructure removal without any economical or social return.
In 1999, the non-profit Friends of High Line was formed, and advocated the preservation and reuse the structure as public greenery. The park consists of different parts, including natural greenery plantings, pebble- ash concrete walkways that unify the trail and parts of the left over sections of the rail tracks were preserved to recall the High Line’s former use and adaptively re-used for rolling lounges positioned for river views.
The High Line is claimed to be a sustainable project, however for it to become what it is today, transforming from an abandoned rail line into a public green park, with all sustainability of High Line as a rehabilitating project, all the construction processes should be analyses quantitatively and weigh against the process of demolishing the railway. Let us discuss with the energy consumption in demolishing a 2. Km steel/ concrete railroad first. According to the Energy Use for Building Construction demolition energy formula, the energy consumption for demolishing a 2. Km long and mm wide steel/concrete structure is approximately 4. 5 billion BTU, which is enough energy to drive a car an average of 12,000 miles a year for 75 years. Moreover, the demolished structure consists of 1650 tons of metal and concrete, with total embodied energy of 300 billion, would go down into the landfill. On the other hand, in order to calculate the energy consumption for the obliteration of High Line, three stages of the construction processes should be taken into consideration.
Firstly, the removals of steel rails, gravel ballast, soil, debris and a layer of concrete, it was necessary to repair the structures and then 35% of the rails and railroad artifacts were returned to their original location. The removals comprised up to 130 tons of steels and gravels. The energy consumed in the removals and replace them back is approximately 0. 5 billion BTU. This energy consumption level is calculated by the use of demolition energy formula from the Energy Use for Building Construction; that includes all the energy consumption of tear down and restoring 35% of the rails, with the total estimated processed area of Simms.
Second stage, after removals, the steel elements was sandblasted to remove the original lead paint. This is processed by 25-foot section at a time using the sandblaster; the total area processed is 24000sqm with the average productivity rate for industrial sandblaster fool sum per hour and 381844. BTL per hour. The total energy consumption for the sandblasting process was 0. 61 billion BTU. Third Stage, the final phase was the construction of the park landscape, the pathways are constructed with a series of smooth, tapered concrete planks with drainage and electrical conduits underneath it.
The total energy consumption for the landscape construction is approximately 3. 3 billion BTU, measured by the embodied energy of concrete per unit x gross floor area of construction x 1. 43 (including all the mechanicals and fixtures). Compare the energy consumption for demolishing the High Line and rehabilitating it, judging by the figures, both of the processes have similar levels of energy consumption. By operating the High Line as a public park, it will continuously consume energy for repairing and maintenance; it will eventually consume more energy than the option of demolishing the High Line.
Nonetheless, by preserving it, it at once save all the 300 billions BTU of embodied energy and has a great potential in driving the city towards a more sustainable direction, including having real sustainable impacts on environment, economic sustainability and, raising social awareness. Contrastingly, demolishing the High Line, the amount of embodied energy would go down into grave for nothing, without generating any social or environmental benefits, instead it would become a huge environmental liability. The environmental sector.
Although the impacts could not yet be quantified, however, the qualitative benefits it has brought to the city cannot be undermined. The High Line’s landscape implements the same technology as a green roof, it effectively reduces storm water runoff by up to 80%, which helps to prevent polluted runoffs and reduces the events of floods. In addition, it reduces urban heat island effect, which the plantation reduces the heat reflecting back into the cityscape, it collaterally creases energy consumption and carbon emission resulted from air-conditioning usage.
All the materials used in construction for the landscape were particularly chosen based on life-cycle costs to reduce the energy cost in replacing components in the future, for example the wood used on the High Line is an FCC certified pipe hardwood, it is sustainable harvested and is selected for its durability and life span of up to 100 years. Most of the plants on High Line are native and drought resistant, so these plants can be better adapted thus reduces the amount of plant failure to avoid replacement cost and energy.
The lighting system been used on Highlight is energy efficient LED lights, which it uses 90% less energy compared to conventional incandescent light bulbs, it contains zero hazardous chemicals and reduces 90% of the carbon dioxide emissions. Evidently, High Line has approached the project with sustainable measures; therefore, it definitely operates more sustainable than conventional public parks without the sustainable measures. The High Line successfully reversed the fate of the abandoned railroad, and becomes a well-known sustainable model for rehabilitation and it generated huge economical and social benefits for the city.
During the planning stage, a 2002 study found that the project is also economically sustainable, with the tax revenues generated by the public park would be greater than the cost of the construction, as well as creating a sustainable public park, with all operating cost and energy been planned sustainable to minimize environmental impacts. The construction cost was approximately 150 million dollars and the estimated annual maintenance cost will be between 3. 5 – 4. 5 million dollars. However the project is estimated will bring over 900 million of tax revenues, due to the increase in surrounding property values after the zone in West Chelsea.
The project was one of the main forces to trigger the development in West Chelsea. In 2005, along with High Line, other former industrial spaces were rezoned to encourage the continued use of former industrial spaces as art galleries. Real estate along the High Line has experienced a rise of 30 percent within the 2012. The landscape is not only a huge economic generator but it also represents a new kind of lifestyle for the locals, which it encourages people to walk and experience the urban space, instead of driving.
It has influenced the society’s alee in sustainability by raising awareness and demonstrating that embodied energy in an old structure could be saved and put into good use. In conclusion, preserving and rehabilitating the structure relics is proven to be an ingenious way of saving energy, while enabling more sustainable methods of urban planning with the use of landscape as a tool. Through the exploration of the project High Line, the energy consumptions of the demolition of the former railway discover the true sustainability of this strategy.
It is evident that although the predicted demolition energy and the energy spent on project construction is similar, he High Line is still more sustainable than the demolition; as by demolishing it, all the embodied energy will be lost into landfill and the energy consumption and cost to be spent are relatively high. On the other hand, the amount of input energy invested in the construction of High Line instantly saved all the embodied energy, and on top of that, it qualitatively improves the sustainability of the city by reducing storm runoffs, urban heat island effect and using low energy lighting systems and resilient native plants.