Archive for the Category ◊ Sustainability ◊

• Monday, May 10th, 2010

Today when we talk about sustainability the first thought that comes to the mind is the environment and biodiversity. It is remarkable here to have a quick look at what  biodiversity means and what is defined to be a clean environment, what are the pollutants, how they are measured and what are today’s main global concerns.

Biodiversity is “the variability among living organisms from all sources, including, ‘inter alia’, terrestrial, marine, and other aquatic ecosystems, and the ecological complexes of which they are part: this includes diversity within species, between species and of ecosystems” (UN Earth Summit, 1992).

Biodiversity is a very important part of environment that today, in order to have a sustainable approach; we need to consider the process Life Cycle Assessment (LSA). For example the global warming and pollutions endanger biodiversity and therefore having the least impacts on biodiversity must be one of the priorities in choosing alternatives.

A clean environment is the one that is free of pollutions or at least has a controllable pollution that does not harm the biodiversity and the ecosystems. Environmental impacts are:

●health & safety



●visual impact

●resource depletion

●global warming

●ozone depletion

●acid rain formation

●depletion of oxygen in natural waters

●toxicity to humans

●toxicity to other organisms

Most of the environmental impacts are caused by pollutions. Receptors of the harm of the pollutants are human, animals, plants, ecosystems, agrisystems, monuments and buildings. The sources are contaminated air, water and soil.

Main pollutants and problems:

●   Carbon monoxide (CO): toxic (binding to hemoglobin impairs oxygen delivery)

●   Oxides of nitrogen (NOX): formation of acid by a series of reactions involving sunlight: Acid rain & Smog

●   Sulfur dioxide (SO2): formation of sulfurous and sulfuric acid: Acid rain & Smog

●   Carbon dioxide (CO2): implicated in climate change.

●   Ozone (O3): respiratory problems (oxidizing agent)

●   Lead (Pb)

●   Particulate Matter (PM, PM10)

●   Trace metals

  1. Cadmium
  2. Arsenic
  3. Nickel
  4. Mercury

●   Hydrocarbons (HC)

  1. Benzene
  2. 1,3-butadiene

In terms of air pollution; air quality is defined to be clean if it contains an acceptable amount of each of the pollutants that has been noted earlier. The concentration of pollutant is measured in ‘parts per billion (ppb) which is more commonly used’ or μ g/m3.

Emissions are measured in terms of the following and again an acceptable amount is defined by environmental agencies based on different factors in different regions.

●   grams

●   grams/kilometer traveled

●   grams/liter of fuel consumed

●   grams/kilogram of fuel consumed


A sustainable society is the one that in its developments considers the life cycle assessment (LSA) as well the futurity. It is crucial that in decision making, other than finance, factors such as environment and biodiversity be taken into account or otherwise the capitals of the society will be endangered. The world today is facing many challenges such as global warming and it requires the attention of political systems all over the world to change and update their regulations based on sustainability and a greener life.

• Monday, May 10th, 2010

It is remarkable here to give an example of what UK’s engineering principles with regards to a sustainable development are and then using these define the term and its applications in the construction industry in more details ;

According to Royal Academy of Engineering, UK, 2005, there are 12 principles of Engineering for Sustainable Development that should be taken into account and are of relevant to be mentioned here:

  1. Look beyond your own locality and the immediate future
  2. Innovate and be creative
  3. Seek a balanced solution
  4. Seek engagement from all stakeholders
  5. Make sure you know the needs and wants
  6. Plan and manage effectively
  7. Give sustainability the benefit of the doubt
  8. If polluters must pollute…then they must pay as well
  9. Adopt a holistic “cradle-to-grave” approach
  10. Do things right, having decided on the right thing to do
  11. Beware cost reductions that masquerade as value engineering
  12. Practice what you preach

Constructions and Sustainability:

Now the question is that how we can achieve a sustainable construction? Firstly, we should compare the alternative solutions putting in mind the sustainability definitions to achieve a sustainable solution.

Looking at the definitions of sustainability we can see that its most important aspect is the future. A sustainable society is defined to be aware of the needs of the future generations and is farseeing enough. It is obvious that this is not the case in most of the societies. The management and political systems are more based on budgets and current economy rather than how the project will look like or operate after a certain life time. They are more concerned with how a project performs during their political or presidency time than the whole life cycle.

It is not surprising any more, especially in the US for example, to hear that a bridge is collapsed or a water system has stopped working and needs maintenance and so on. For example a report from American Society of Civil Engineers2 (ASCE) in 2005 concluded that 27 percent of 600,000 bridges in the US are structurally deficient or functionally obsolete and it would cost $9 billion annually for 20 years just to fix the bridges. For such problems who should be blamed? Is it the erosion and nature to be blamed? Is it an inevitable disaster that no one is responsible for? Or it is the current government that should be blamed? The answer simply is, in fact, no one is actually now responsible for the old infrastructure. These old systems now are subjected to the end of their life time. However, there are some responsibilities about the maintenance of these infrastructures that is out of the main discussion of this paper.

The solution to such problems was 50 or 60 years ago when they started building these bridges, in particular, and the question is whether they had the option of building other alternatives such as Tunnels that are known to have one of the longest life time among the infrastructure buildings. It might have been a more sustainable solution when building these infrastructures. But again we can argue that sustainability is a new defined term and has been taken into the considerations just over the last few decades and the revolution of suspended bridges as well as steel structures at that time was the main encourager for that governments and engineers to choose bridges over tunnels.

Now leaving the past behind and learning from its lessons we should certainly be concerned why governments are still on that old fashion path. Why they still assign the projects to absolutely unsustainable but less pricey options. The problem is further than it seems. It is a political and systematical issue. Policies of the governments to this direction must change from the roots. It must change this based on budget and capitalistic decision making that looks at how much money is available rather than looking more responsible at the issues and being farseeing enough.

To illustrate the point signing the Kyoto Protocol by the US government can be a good example. Of course every American as well as the government wants to sign such important document which is not just about Americans but about the whole world.  It is the system that does not allow the government to sign the protocol. Discussing the failure of the system to respond to sustainability and global issues is another subject that requires its own paper and discussion. Let us hope the new American administration as promised put its feet into this direction and lead the sustainable path.

• Monday, May 10th, 2010


When it comes to sustainability, the most important issue is its definition . Therefore, at the beginning it is remarkable to mention some of the worldwide accepted definitions of sustainability over the last few decades:

●   A sustainable development “meets the needs of the present without compromising the ability of future generations to meet their own needs ”  The Bruntland Report (WCED, 1987, p8)

●   sustainability is “improving the quality of human life while living within the carrying capacity of supporting ecosystems”  (IUCN, WWF and UNEP, 1991)

●   A sustainable society is “one that can persist over generations, one that is far-seeing enough, flexible enough, and wise enough, not to undermine either its physical or its social systems of support.” Meadows et al (1972)

To priorities and manage each development, at least in Europe, it has been agreed to define and rank the capitals of a society as following:

  1. Natural
  2. Human
  3. Social
  4. Manufactured       (Ekins et al, 1992)

and fifth capital – financial (Forum for the Future, see Parkin et al, 2003)

As we can see finance is the fifth capital according to ‘Forum for the Future’ if it is to be called a capital in a society. However; this is not always the case worldwide. Unfortunately, in some countries and societies finance is considered to be one of the main priorities if not the first priority and this has leaded the world to a disastrous position over the last few decades. Problems such as global warming, acid rains, ozone depletion, smogs, and etc. appear and endanger the other four main capitals of a society or the world in general.

On the other hand today’s societies are expected to think wider and, as a main aspect of sustainability, consider the whole life cycle assessment (LSA) of the alternatives when building a project. This means studying in detail the stages of making, using and disposing of a product before choosing the option. Stages which start from extraction of raw materials needed for the project to design, formulation, specification, processing, manufacturing, assembly, construction, packaging, use, maintenance, refurbishment, re-using and finally recycling and disposal1. A sustainable construction is the one that has taken all these stages into account, before the construction starts, to have the least effect on the environment and biodiversity as well as the capitals that have been eluded earlier.