Monday, January 28, 2008

Benin: Rising sea waters threaten property and jobs

“Huge breakers constantly battering Benin's coast - and the rest of the shoreline on the Gulf of Guinea - are starting to take their toll,” writes South Africa’s IOL. “Ivory Coast, Ghana, Togo and Nigeria are also fighting to stop the sea from gulping up chunks of land.”

The erosion to Benin’s coastline is staggering. East of Cotonou, since the country’s independence from France in 1960, the beach has retreated some 400 meters, claims a member of the UN Environmental Program. The encroachment of water affects properties along the beach in obvious physical ways, but subtle effects are now seen. For example, fishermen now experience problems getting their boats through the incoming rush of tide.

The story refers to a study from Columbia University (which I can’t find) that estimates sea water levels could rise nearly 50 centimeters by the end of the century. Newly minted Nobel Peace laureates, the Intergovernmental Panel on Climate Change, says sea levels could rise between 20 and 60 cm in that time period.

But these predictions due to Global Warming are not the only problem exacerbating issues facing West Africa’s coast. Local human activities can also be blamed. The construction of two massive dams, one in Benin and one in Ghana, on rivers near the coasts send discharge far into the ocean that is usually meant to stabilize the shoreline. People make cement by using beach sand – more than one million cubic meters each year in Benin alone, according to IRIN. We must also take into account all the land lost from dredging the coastline to build the region’s major ports in Abidjan, Tema, Ghana, Lomé, Togo and Cotonou.

Who knows how much this has affected places like Grand Popo, a small town near Togo’s border with Benin, that now rests largely underwater. Could a big urban area like Cotonou find itself submerged?

From the IOL story:

A number of other studies have underscored just how quickly most of Cotonou, Benin's commercial capital, could disappear under the waves.

One by the French firm SOGREAH-Laboratoire DEFT said: "If nothing is done before 2025, the coastline will lie 950 metres farther inland than it did in 1963."

Hardest hit would be the section of Cotonou known as Les Ambassadeurs, which the French study said would be swallowed up completely, as would the road that links the administrative capital Porto Novo to Lagos in Nigeria. Other districts of Cotonou could follow pretty quickly, it warned.

But it was only in September that the government banned local construction companies from pumping sand from the seacoast and told them to use sand from rivers instead.

Benin's next big plan is to build dikes to protect its 125-kilometre coastline. The €50-million project financed partially by the World Bank is set to start in first half 2008.

"Our first goal, stopping the extraction of sea sand, has been achieved. We are now going to build dikes in two directions starting from Cotonou channel: towards the Togolese border and towards the Nigerian border," Urban Planning Minister Francois Noudegbessi told AFP.

UNEP experts, however, said that only a full regional dike would be beneficial, stretching at least along the five countries from Ivory Coast east to Nigeria.

Economic considerations
Its coastline brings in a good portion of Benin’s GDP. Continuing sea level rises could easily destabilize the country’s socio-economic-environmental balance: Great financial resources may have to be diverted to build dikes and other water control systems; those who rely on the water for work, like fishermen, may struggle to keep up with the great changes in their occupations; coastal villages may be forced to move inland, possibly creating land tenure issues; the loss of coastal wetlands may affect the availability of clean drinking water.

This study tries to take that all into account. By reviewing land height and population density, researchers predict that if West African coastlines rise by one meter over the next 90 years, 2.3 million people could be directly affected, costing economies as much as $3.6 billion when compared to GDP. If water levels increase by five meters, it will affect 3.3 million people and total $4.9 billion in GDP.

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