Water Resources Engineering (WRE) connects engineering hydrology and hydraulics with global, economic, environmental, and societal issues. Our student Naomi Henry makes this connection here…

The report entitled, Seychelles Damage, Loss, and Needs Assessment (DaLA) 2013 Floods, was published by the Seychelles Government with the support of the European Union, the United Nations, and the World Bank in June 2013.[i] This report relates to the WRE domain of hydrology specifically, in terms of the occurrences of floods and the impacts they are having on the nation of Seychelles. This report discusses the major impacts that the tropical cyclone Felleng of January 2013 had on the country. In addition, it discusses the likely increased susceptibility to similar disasters in the future and suggestions to reduce the amount of losses and damages that will be incurred in the future.

The report suggests that more efforts need to be made in establishing proper flood risk assessments, notably in areas with repeat incidences. According to this report, there are three major factors contributing to Seychelles vulnerability to flood disasters. These factors are (a) natural vulnerability as a result of geomorphology; (b) changes in rainfall believed to be a result of climate change; and (c) risk as a result of insufficient regulation/management and non compliance. The steep slopes combined with insufficient and poorly maintained drainage systems allows for overland flow and pooling of water in the coast regions. The projection of Seychelles’ susceptibility to climate change is consistent with a study published in the Journal of Climate, which concluded that there is a global trend towards an increase in annual maximum daily precipitation.[ii]  If the winter rain precipitation patterns become more erratic, prediction a floods doesn’t seem to be a viable option for flood damage reduction.

With Seychelles being a developing nation, and with a challenging topography to work with, it is not feasible, nor is it cost effective to rely solely upon large-scale “hard” engineering projects. The report mentioned a project in Brazil that promoted green space and restricted development in flood-prone zones as a cost effective way of risk management. A study was conducted in the United Kingdom, which analyzed the effectiveness of non-structural risk management techniques. It was concluded, that with strong government involvement, non-structural measures have a greater long-term impact in improving flood risk scenarios.[iii]

The authors believe that a comprehensive analysis should be conducted. A database needs be created which would contain maps and reports on high-risk zones, which will aide in informing urban development projects and future land use plans. The government needs to be more proactive in enforcing compliance of all construction projects especially those in flood zones and in addition to this, structures in high risk areas should be relocated. In the report, it was mentioned that in recent years Seychelles has been afflicted with about four major events. The report mentions a need for government involvement but fails to mention what has “prohibited” them in being actively involved in developing solutions to avoid crisis.

Flooding in Seychelles impacts the economy, the environment, as well as the society of the nation, which are all interconnected. The economy of the nation is heavily reliant upon tourism, which is reliant upon the maintenance of a pristine environment and biodiversity. Damages and losses due to floods not only pose a risk to the intrinsic value of the environment, but to the economic value as well. Additionally, disasters impede productivity, in restricting movement around the country for citizens to attend school or work. Furthermore, the presence of floods pose health risks from an increased of mosquito breeding grounds from stagnant waters, damage to food crops, as well as when sewage plants become overwhelmed and contaminate the drinking water supply.[iv]

Damage as a result of flooding, landslides, and rockslides after Tropical Cyclone Felleng, 2013

Damage as a result of flooding, landslides, and rockslides after Tropical Cyclone Felleng, 2013

Main areas affected by the Tropical Cyclone Felleng, 2013.

Main areas affected by the Tropical Cyclone Felleng, 2013.

References:


[i] Government of Seychelles. Seychelles Damage, Loss, and Needs Assessment (DaLA) 2013 Floods. 2013

[ii] Westra, Seth, Lisa V. Alexander, Francis W. Zwiers. Global Increasing Trends in Annual Maximum Daily Precipitation. Journal of Climate. 2013 ; 26: 3904–3918. doi: http://dx.doi.org/10.1175/JCLI-D-12-00502.1

[iii] Dawson, R. J., Ball, T., Werritty, J., Werritty, A., Hall, J. W., & Roche, N. Assessing the effectiveness of non-structural flood management measures in the Thames Estuary under conditions of socio-economic and environmental change. Global Environmental Change. 2011; 21(2): 628-646. doi: http://dx.doi.org/10.1016/j.gloenvcha.2011.01.013

[iv] Haines, A., Kovats, R. S., Campbell-Lendrum, D., & Corvalán, C. Climate change and human health: impacts, vulnerability and public health. Public Health. 2006; 120(7); 585-596. doi: http://dx.doi.org/10.1016/j.puhe.2006.01.002

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