From Lifestyle - Reuters
By Anton Ferreira
Model 'Eco-City' Could Soon Rise in Senegal
WASHINGTON (Reuters) - The West African nation of Senegal could soon be the site of a bold experiment in solving the housing problems of the world's poor -- a model town built of sand that harnesses the sun and wind for energy.
Senegalese President Abdoulaye Wade told Reuters he wants to build the town of about 20,000 houses using a construction method developed by Iranian-American architect Nader Khalili known as "Superadobe."
In its simplest form, it consists of building circular, beehive-shaped houses with sand-filled tubes placed one on top of the other with strands of barbed wire between the layers to provide a Velcro-like grip.
The walls gradually curve inward at the top to form a self-supporting, domed roof that needs no timber for support -- an important factor in countries afflicted by deforestation. The tubes in which the sand is packed are usually made of woven polyester, but hessian bags can also be used.
Wade, in an interview from Dakar last week, said he heard of Khalili's work when Senegal was looking for ways to help thousands of people made homeless by severe flooding in the northern provinces earlier this year.
"I called him, I invited him to Senegal to talk with him. ... So I will provide him with land, he will choose the place, maybe in Dakar, maybe in a suburb of Dakar, and I am ready to experiment with this system," the president said.
"I am interested in building a new city with this method."
Wade, a champion of African development, said better housing was a pressing issue for Senegal, particularly after the floods in January.
SENEGAL SEEKS LOW-COST SOLUTION
"My problem was how to build, at low cost, houses for the people. ... The fundamental idea was, it should be possible to build a house better than our traditional house, that can be modernized, at a very low cost."
He said one of the attractions of the Khalili system was that it was so simple, people could build their own homes, providing their own labor, and the building materials were close at hand.
"In terms of architecture, I think this type of building will be well adapted to the climate," Wade said, saying the thickness of the walls -- about two feet (60 cm) -- would help insulate residents against heat and cold.
"This type of construction is adaptable to our traditional construction, the African hut," he said.
Wade said Senegal would approach international donors like the World Bank (news - web sites) or the European Union (news - web sites) for help in funding the project.
The project so far is little more than an idea, so no estimates can be placed on what it would cost. The infrastructure of roads, water and sewage would be the most expensive component, but Khalili believes the houses themselves would cost about 50 percent less than houses of a similar standard built by any other method.
For Khalili, who visited Senegal last month with his partner and fellow architect Iliona Outram and his brother Nasser Khalili, an infrastructure specialist, building a model city in Senegal would be a giant step toward attaining a long-standing dream.
"As far as I'm concerned, truly the whole treasure is sitting right there: the land is there, the water is there, the people are extremely nice, very peaceful and cooperative," he said.
"It's a very important project, really it can be a breakthrough."
Khalili and Outram teach the Superadobe system at their Calearth Institute in Hesperia, California (http://www.calearth.org/), and are using the method to build a museum for the city.
Because they are in an earthquake (news - web sites) zone, the buildings have been subjected to stringent state building code tests -- which they passed with flying colors.
Their strength and stability derives largely from their domed construction, much like the shape of a chicken egg allows the thin shell to withstand relatively high forces.
Because a Superadobe house has no conventional roof, there's nothing to be ripped off in a hurricane; the solidity of the structure means it will remain standing in a flood.
Many people who have trained at Calearth have gone on to build their own Superadobe homes, in the United States and abroad, but Khalili has no idea how many.
"Now and then people send us photographs of what they have built," he said.
A SUSTAINABLE TOWN
Despite great interest expressed in its work by development professionals at the United Nations (news - web sites) and elsewhere, Calearth has yet to be given the opportunity to put its ideas for low-cost, secure, comfortable shelter into practice on a large scale. The Senegal project would be the first of its kind.
Khalili said Calearth had trained several apprentices who would be eager to go to Senegal to help local people get started.
"The way I see it, the sun that exists in Senegal is perfect to do solar energy for a sustainable town and of course you could use natural energy like wind for cooling as well, and they use the earth to build just about all the structures," he said.
"The technology to create a sustainable town exists today fully."
Khalili's Superadobe homes borrow heavily from traditional Middle Eastern architecture, incorporating for example wind funnels extending above roof level that catch breezes and bring cooling air down into the living area.
Khalili said he and his team had visited the flood-ravaged north during their trip and had been moved by the plight of the victims.
"The solution seems so close at hand: just some knowledge of how to dig what is under their feet, how to add some bags and barbed wire and tie it all together, how a sensible design can save them from the next flood, storm or natural disaster," he said.
Copyright Reuters
