Sustainability issues

INTRODUCTION

Sustainability is the prevention or reduction of the effect of environmental issues for humans to live a sustainable life and as part of the effort is to return human use of natural resources to a sustainable limit at which it can be replenished. The fact that sustainability issues affect the ways in which project are been chosen, planed, designed or implemented does not mean human life should be stagnant, rather, according to Mahri (2001), environmental issues needs to be put into consideration as a principal means of achieving sustainable development, also sustainable development enhances the quality of life

(Pun et al., 2001).

This report shall put lights on a critical evaluation on current academic thinking as regards how sustainability issues can affect the way civil engineering projects are chosen, planned, designed and implemented.

CHOSEN PROJECTS AND SUSTAINABILITY ISSUES

Civil Engineering is the construction of systems that aim to improve life in different ways (Tavares, 1999). These are engineering field that brought about bridges, dams, roads, buildings, fabrications, etc. and these constructions have either a direct or indirect ways of polluting the environment during their construction processes. Like in the construction/fabrication of buoys, piles, vessels, where blasting and painting are carried out on-site, also hammering activities on-site, excavation and foundation works, transportation of raw materials, radiography (X-ray). All these processes affect the environment not alone but human lives such s waste generation requiring land storage, alteration of soil, emissions of substances into the atmosphere (e.g. grits and sand blasting operations) and water. However, according to Gangolelles et al., (2008), environment has been considered as among the project performance in construction organisations which environmental management system (EMS) has been implemented to improve environmental performance.

Constructions

A sustainability issue of civil engineering structures has been a problem that's been ongoing for the construction industry and society (Samir E.C., 2009). The construction industry in the UK is under increasing legal and commercial pressure to become more sustainable (Ian Holton, Jacqui Glass, Andrew, D.F. Price, 2010). Roome Cited in Ian Holton, Jacqui Glass, Andrew, D.F. Price, (2010), and it states that managing sustainability aim is for a strategic development and changes in organizations. Acording to Smith (1991) cited in Yip (2000), the construction industry is accountable for 50% of Co2 emitted worldwide through the utilization of fossil fuel which results to a quarter of green house gases. UK contributes 55% of Co2 to the total gas emitted (Ghanbari Parsa and Akhavan Farshchi, 1996). Also, occupants of buildings contribute to Co2 emission this is due to the heating and cooling systems. By estimate it has been observed that 78% of UK houses use natural gas for heating of their buildings while few uses electricity (Lowe 2004). According to Olgyay and Herdt, (2004), three-quarter of this energy is obtained from fossil fuels. Most countries are not sustainable as far as fossil fuel management is concerned (V.S. Ediger et al., 2007)

Oil and Gas Industries

The oil and gas industries like the Upstream and Down-stream sector cause water, noise and air pollution. They bring about negative effects such as damage to agriculture, landscape and forestry, contamination of water or seas and all these effects bring human and organisms to an unsustainable life. According to Akeredolu F.A. and Sonibare J.A (2004), Flaring is a universal means of discarding flammable waste gases in the upstream oil, gas, downstream refining and chemical processing industries and flare is an open-air flame that is exposed to the weather elements, particularly winds. Flaring of associated gas from oil exploration has a number of consequences on the environment. (Elisha J.D., Leonard S.B and Tano D.A., 2008). Nigeria tops the list of ten countries responsible for 75% of gas flaring emissions in the world. According to World bank cited in Elisha J.D., Leonard S.B and Tano D.A., (2008), Nigeria flares 16% of the total associated gas which is the highest amount by any country in the world. This has affected the growth and development of crops especially cassava plant in the Niger Delta, Nigeria and made food very expensive in that part, this has also result in conflicts between local community, Government and oil companies, which have made companies relocate back to some other countries like Angola.

Construction

The constructions of bridges, roads and highway cause air, noise and water pollution because some techniques used during construction like blasting, have been found to affect human health and could also lead to destruction of property within the area of construction. (Ozer, 2008).

By and large, construction projects diminish land in form of landfill waste and space aquired by the project. Previous studies have shown possibilities of construction waste contributing to more than half of UK's landfill waste (Ferguson et al., 1995 cited in Faniran and Caban, 1998). Related studies have also shown the following percentages of construction waste in landfills: 19% in Germany (Brooks et al., 1994 cited Faniran and Caban, 1998), 26% in Netherlands (Lanting, 1993 cited Faniran and Caban, 1998) and 13% - 15% in Finland (Heino, 1994 cited Faniran and Caban, 1998).

PROJECT PLANNING AND SUSTAINABILITY ISSUES

After the hurdle of project selection and its sustainability issues, then next is project planning. Environmental management plan, contingency plans and equipment that is to be used to carryout a specific work on all construction contract should be specified, in order to have a friendly environment.(Pun et al., 2001).

A project is said to be unique when it has a proper budget in place and realistic delivery time. It has been described by Coventry et al., (2001 cited in Dainty and Brooke, 2004) that studies have shown that construction wastes are associated to design changes. Also, inadequate funds and timing of project finish date tends to encourage wasting and destruction of materials, thus generating waste on construction site which could also be a hazard to human life.

Adequate control measure should be in place on material control, so that during material order, the required quantity needed should be ordered and ensure its delivered as at when due, this will reduce the long storage and improper handling of materials and condole waste generation on site (Dainty and Brooke, 2004).

Equipments and operations that generate noise pollution should be well controlled and noise monitoring should also be introduced. There are measures which exist in some countries; most of them which are governmental form of laws, to control noise generated industrial operations. This form of law is to regulate the usage of machineries with high noise level to operate at a favorable time (Yip, 2000). Also reduction of personnel at workplace exposure limit should be a perfect way to reduce the impact of noise on human.

PROJECT DESIGN AND SUSTAINABILITY ISSUES

Building and Transportation Infrastructure Designs

Buildings should be approached with a system and process which will apply and integrate essential values into building performance. Thus, construction projects should best be determined at the design and planning stage (Leaman et al., 2001; Mohsini, 1989 cited in Pheng et al., 2008). Future impacts on environment and habitants should be put into consideration when designing buildings. Moreover, things like energy consumption which in future has effect on vision, acoustics and air quality and lead to health issues and other unsustainable issues that might even lead to low productivity at work place when absenteeism has become rampant. General lightening and improper citing of openings in buildings, environments where contaminant-producing machines are cited close to occupants brings low quality air and poor vision from the lightening (Pheng et al., 2008). Analysis during the last 7 years on environmental impact on residence carried out by Adalberth et al., cited in Oscar ortiz, Francesc castells and Guido sonnemann, (2009), on Life Circle Assessment, shows that the factors with the greatest environmental impact was electricity which occurs when its on use.

Studies have shown that buildings designed and constructed with insulation on both roof and help enormously to reduce heat loss, hence carbon dioxide emissions are reduced. It was confirmed by Shorrock and Utley (2003 cited in Lowe, 2007) that there was a 40% reduction of heat loss in UK buildings in 2001 as an outcome of roof insulation.

Sustainability of Construction Materials and Designs

Sustainability of Civil Engineering structures has been an ongoing issue in the construction sector and the society in whole. Materials used for construction also have sustainable issues with the way construction projects are designed, most of the materials use up energy when in the manufacturing stage or transporting materials to site. Materials like cement, steel and concrete, aluminium require much energy during their manufacturing and transportation phase (Morel et al., 2000; Pearlmutter et al., 2007). However, the durability of materials should also be considered in the design phase, according to Samir E. Chidiac, (2009), described the durability of concrete in particular to depend on the qualities of material, design, construction and condition its been subjected to during and after its manufacture.

Therefore, in selecting construction materials, lifespan of the material should be highly considered because a good combination material having a high lifespan makes projects last long and brings its maintenance and demolition rate low. As described by Morel et al., (2007), stones masonry and concrete buildings have lifespan of 200 and 100 years respectively.

A Life Cycle Assessment done on steel bridges by Widman (1998) revealed a high emission of carbon dioxide due to steel and cement production. The changing of roads to railways, efficient use of coke and coal in steel production and the use of bio-fuels by vehicles is thus suggested.

PROJECT IMPLIMENTATION AND SUSTAINABILITY ISSUES

Implementation is a phase in projects where all planned activities is brought into play. However, material loss in building industry is always seen as normal, and according to McGrath and Anderson, (2000) cited in Dainty and Brooke, (2004), wastage rate in site construction is from 10% to 15%. According to Hore, et al.,(1997) cited in Ajayi, et al., (2008), for every 100 houses built there is enough waste material to build another 10 houses. Similarly Akinpelu (2007) cited in Ajayi, (2008), which is of the view that on most capital projects resources from which waste is generated, account for more than 60% of their production costs.

Most construction waste are drain into landfills which increases the burden on landfill and operation, also result in soil and water pollution which are source of environmental hazards. Proper and effective way of curtailing this is to ensure a construction waste management is implemented and possibly a landfill tax imposed also. The reduction and recycling of waste yields to increase in lifetime landfills and exploitation of natural resources use in material manufacture (Ajayi, et al., 2008).

CONCLUSION

After thorough analysis on how sustainability issues affect project, it was observed that civil engineering projects do more harm by making human leave unsustainable lives and deplete the environment. Much work had been done on civil construction projects and emphasis has been more on the design stage because it describes what the project would look in future.