jueves, noviembre 29, 2007

MEDIO AMBIENTE: 'Deje fluir al sanitario fuera del ciclo del agua'

IPS News

By Zofeen Ebrahim

SEOUL, Nov 25 (IPS) - The one message that came across at the just concluded general assembly of the World Toilet Association (WTA) was that conventional flush toilets are not only environment unfriendly but are also a serious public health hazard.

And while the United Nations estimates that 2.6 billion people are living without proper sanitation and without access to potable water, those using flush toilets are converting precious water into dangerous effluents.

Sanitation experts who gathered in the Korean capital for the assembly, that concluded on Sunday, called for a major paradigm shift and even a ‘back to nature’ approach to the disposal of human waste.

"We are on the wrong track," said Hubert J. Gijzen, a biotechnologist representing UNESCO’s Indonesian office.

Newer ways, all agreed, were needed to be developed to dispose human excreta. If flush toilets have to be used they must be redesigned to reduce water consumption, or else use recycled water.

‘’The current conventional sanitation systems will not be able to achieve the (United Nations’) Millennium Development Goal,’’ said lawmaker James D. Mamit from Malaysia, who is environment advisor to its state of Sarawak.

Ecologists are calling for a major sanitation reformation, along the concept of ‘EcoSan’ or ecological sanitation, that would contribute towards water conservation and mitigating surface and ground water pollution, thereby reducing the risk of water-borne diseases.

One of the technologies being widely advocated involves separation of faeces, urine and grey water, thereby minimising the volume of water needed to flush away excreta. Valuable nutrients are recovered, and the residual matter converted into biogas and used as fuel.

This rethinking would not only require innovation, research, training and awareness-raising but an abandonment of conventional water management while developing strategies that are effective, low-tech and low-cost as well.

Mamit suggests the inclusion of EcoSan concept at the policy level and suitable changes to existing legislations in many countries that favour conventional, centralised sanitary systems.

"It is understandable that these impacts were not foreseen at a time when the world population was only around one billion people, and global change pressures of today were not foreseen," said Gijzen. But with climate change, population explosion, major urbanisation, which has in turn led to informal settlements, the old method of removing human waste is not sustainable.

"No doubt water is life, but it is also a killer because we are contaminating our water," says Gijzen, adding that wastewater treatment was costly and still does not produce safe and pathogen-free effluents.

"In developing regions, effluents get dumped into water courses untreated due to the phenomenal costs of sewer collection systems and high rate of wastewater treatment technology. And with more than five billion people living near contaminated water we can never hope to get rid of water-borne epidemics or meet the Millennium Development Goals."

If taking the "toilet out of the water cycle" suggestion is taken seriously it is possible, Gijzen says, to have greener, eco-friendly cities 50 years from now while providing a toilet which everyone on the globe can afford. ‘’Living in a home next to a water course, which not only has crystal clear water, but which you can you can actually drink from, can be a reality,’’ says Gijzen.

One promising design for a toilet, that attracted attention at the Seoul meet, actually recycles water using a biological and physical process and sends it back into the toilet bowl. Keon Ki- Lee, a Korean engineer who designed the system, says the toilet can be set up with or without a waterline or a drainage system and is environment friendly because the system does not produce a water discharge. "It has been received favourably by our local government," explained Lee

A new UNESCO project Sustainable Urban Water Management Improves Tomorrow’s City’s Health, or SWITCH for short, already implemented with a hefty budget of 32 million US dollars for a period of five years, is already being implemented.

A whole range of eco-friendly models are being tried and tested in nine demo cities which include Bogota, Beijing, Ghana, Lima, Colombia and Alexandria. Schemes include those for the rational use of water, effluent reuse, dry sanitation, urine separation and nutrient recovery.

Mamit shared the experience of an EcoSan model established in two residential rural schools in Sarawak where toilets were modified to accommodate one flushing in a day using up to two litres of water. The biogas produced has helped save over 500 dollars per month that was spent on buying cooking gas for the school kitchen.

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