Environmental Assessment For Upgrading Existing Defences In Copperas Bay Essay.

Discuss about the Environmental Impact and Life Cycle Assessment.

Evaluation of Two Alternative Options

Undertaking environmental assessment prior to planning of any construction works is necessary (Nuissl, Haase, Lanzendorf & Wittmer, 2009). The current scope of evaluation includes two alternatives Option A and Option B as a line of defence for upgrading existing defences in Copperas Bay. The Copperas Bay area has been important for roosting, wildfowl species and feeding waders. There is a mudflat nearby to the area of proposed work as they form important feeding region in case of tide rise. The local environment analysis reveals higher parts of the intertidal area of the Copperas Bay and Stour Estuary have presence of saltmarsh plant (Data, 2015). The Stour Estuary had experienced rise in sea level with increased erosion. In this analysis the positive and negative impacts from the construction will be evaluated in terms of solving development problem. Mitigation strategies are developed for those impacts which have significant consequences. 

This option includes hard defence type of mechanism where narrow embankment of 820m long with length of 30m wide of armouring in a seaward face. The hard structure will be constructed will reflect wave energy in the intertidal zone.

In this Option, a hard structure will be constructed and it will act as a defence. The positive aspect of hard defence once constructed will act as a permanent structure and will prevent the waves from further entering bay land area. The construction will include stone columns with sand and gravel filling and then rock fill before the mudflats that are existing. This will prevent the water levels from damaging the railway lines. Therefore, it will help increase tourism and connectivity to the area. The enhanced connectivity will provide development of the area implying betterment for the local community. The current defence structure in the bay area is a hard defence with rock bonded pavement. Further construction of hard defence will increase concreteness of the structure and save construction costs on damages to railway lines and nearby road. The hard defence will be able to break down the tidal energy and reduce impact, which it earlier had.

There are a number of negative aspects of this construction. Firstly, the construction work is infeasible due to the close proximity of railway lines. When construction work will take place, the railway connectivity will have to be halted. Secondly, this structure has potentiality to cause erosion in the nearby beaches, saltmarshes as well as mudflats. Erosion to the nearby beaches, saltmarshes and mudflats would have significant environmental impacts on feeding waders, wildfowl species, especially to the saltmarsh vegetation. This would add to the bare mud and algae development in the region, which will in turn impact the ecological balance there. Construction of this embankment would cause a loss of 1.4ha of the SSSL.

Positive and Negative Impacts of Option A

Mitigation strategies will aim at identifying optimum option for each case. Generic types of mitigation include downscaling or limiting, avoidance, impact reduction by redesigning, cleaning up, providing substitutes and accepting trade-offs.    

In order to mitigate the negative impacts on the railway connectivity, work on the defence construction will have to be conducted when rails are not operating and within breaks such as during nights (Van den Heede & De Belie, 2012). This will help prevent loses occurred to railways and also allow construction work to have significantly higher costs.   

The large proportion of land area that will be used for construction this fence will have no direct consequences. Such large land areas will need to be obtained at substantial costs along with material costs (Schaltegger & Burritt, 2017). Thus, in order to mitigate this negative impact a design has to be obtained that requires least possible land area.

The erosion to nearby beaches and mudflats as well as saltmarshes can be mitigated by placing the defence at an inner area compared to its current location (Höjer, 2008). Bare soil erodes easily, hence either dust has to be sprayed or grasses or quick growing species has to be planted. The defence can be constructed within the land area keeping a distance of 1 kilometre from the saltmarsh but that would imply tremendous costs.

In case of soft defence, a length of 820m and a wider 150m with a gently sloping embankment with locally dredged sand will be constructed. The defence will be constructed by pumping mechanism and dredging will be undertaken for a period of two months for entire night and day period. EIA will not be undertaking the project and Harwich Haven Authority will be conducting dredging, for their capital dredging programme for enhancing navigation. The soft deposit will include construction after the existing mudflats and then constructing deposit levels. The deposit will be constructed before the railway line. There will be no obstruction to the railway track.  

The construction will not make use of hard structures as in soft defence there will be usage of dredged sand. In order to construct the defence water and materials will be generated. The most important environmental impact of this method is that it absorbs wave energy and does not reflect it to cause erosion.  

The pumping of water with dredged materials will make the area infertile by washing out sediments that is deposited in the area. The site would lose out on its attractiveness for birds. The material supplied for the project will be by waterways, which will lead to generation of traffic, additionally there will be noise and dust. The construction would require 3ha of the SSSI. This is a loss of huge land area for the construction work.  

Mitigation Strategies for Option A

The option is the best suited for minimising environmental damage; however the negative aspects and consequences need to be considered (Tayibi, Choura, López, Alguacil & López-Delgado, 2009). Strategy for reducing washing of sediments from the area will include digging deep such that surface area where sediments are deposited remains unaffected. Predicted irreversible damage that is caused to sensitive soils requires excavating by restoration process. Drainage must be managed to reduce soil erosion.  

Construction work can include incorporating some invertebrates in the area such that birds are able to feed on the same. The project will need to plan for sourcing its materials in an appropriate manner by appropriate scheduling such that traffic from waterways can be reduced significantly. In order to reduce noise, a noise control mechanism can be adopted which involves a machine that is capable of reducing noise (Petts, 2009). Dust cannot be reduced in the construction project. The usage of land area can be managed by careful planning and implementation. 

Conclusion

Current environmental norms, practices and policies aim sat protection of the natural environment and coastal erosion. Though defences are generally considered to be undesirable in nature. Copperas Bay is of extreme strategic importance internationally due to wading birds. Evaluating positiveness and negativity of both the options, leads to the consideration that Option B is more suitable when compared against Option A. As Option B is more environmentally friendly and requires easily sourced materials. The positive aspects from Option B are greater when compared against Option B, implying that it should be accepted as an alternative. In the current situation, the following recommendations would allow development of an environmentally friendly defence mechanism.

• Permission needs to be sought from Environmental Boards regarding construction of such defences. A detailed description containing points of positive and negative impacts for each option needs to be submitted. Once they provide their permission, only then it is better to go for such constructions.
• The Protection of Birds needs to be consulted as they might have some valid inputs into the project. Their point of view in constructing can help avoid future challenges in such work. It will also prevent them from hindering of such work activity.   
• The organization which will be considering development in the area can partner with local authorities and agencies for sourcing materials and other resources. This will help reduce their costs significantly.
• Apart from considering environmental impacts on the species, environmental impact from construction on pollution to the local air quality and water quality has to be analysed in great detail.

References

Data, M.E., 2015. 2003-2012 Eastern Inshore Fisheries and Conservation Authority (Eastern IFCA) River Stour and Orwell Peacock Fan Worm surveys. Accessed from https://data.gov.uk/dataset/910feb76-2c6c-4752-9980-3f25c889bbba/2003-2012-eastern-inshore-fisheries-and-conservation-authority-eastern-ifca-river-stour-and-orwell-peacock-fan-worm-surveys

Höjer, M., Ahlroth, S., Dreborg, K.H., Ekvall, T., Finnveden, G., Hjelm, O., Hochschorner, E., Nilsson, M. and Palm, V., 2008. Scenarios in selected tools for environmental systems analysis. Journal of Cleaner Production, 16(18), pp.1958-1970. Accessed from https://www.sciencedirect.com/science/article/pii/S0959652608000188

Nuissl, H., Haase, D., Lanzendorf, M. and Wittmer, H., 2009. Environmental impact assessment of urban land use transitions—A context-sensitive approach. Land use policy, 26(2), pp.414-424. Accessed from https://www.sciencedirect.com/science/article/abs/pii/S0264837708000665

Petts, J. ed., 2009. Handbook of Environmental Impact Assessment: Volume 2: Impact and Limitations (Vol. 2). John Wiley & Sons. Accessed from https://books.google.co.in/books?hl=en&lr=&id=M4iv8HZIvuIC&oi=fnd&pg=PR5&dq=analysing+environmental+impact&ots=dXc_SgVpBM&sig=2xVtnslZOnxwlixyV4yX8EL_VZU#v=onepage&q=analysing%20environmental%20impact&f=false

Schaltegger, S. and Burritt, R., 2017. Contemporary environmental accounting: issues, concepts and practice. Routledge. Accessed from https://www.taylorfrancis.com/books/9781351282512

Tayibi, H., Choura, M., López, F.A., Alguacil, F.J. and López-Delgado, A., 2009. Environmental impact and management of phosphogypsum. Journal of environmental management, 90(8), pp.2377-2386. Accessed from https://www.sciencedirect.com/science/article/pii/S0301479709000784

Van den Heede, P. and De Belie, N., 2012. Environmental impact and life cycle assessment (LCA) of traditional and ‘green’concretes: literature review and theoretical calculations. Cement and Concrete Composites, 34(4), pp.431-442. Accessed from https://www.sciencedirect.com/science/article/pii/S0958946512000054