聯合國環境規劃署（UNEP）執行主任史坦納（Achim Steiner）舉出肯亞沿海都市曼巴沙（Mombasa）為例，該城的西莫拉特瓦（Shimo la Tewa）監獄採用廉價的方式解決衛生問題，還帶來其他好處。透過囚犯勞務的方式，監獄的廢水先經自然濕地過濾，成為所謂的「黑水(black wastewater)」，再提供灌溉及魚塘使用，以生產自行食用或對外販售的糧食。
A lack of political will remains the greatest obstacle to efforts to reduce the number of people without access to basic sanitation and clean, running water, UN Secretary-General Ban Ki-moon said Saturday in a message to mark World Water Day. This year, World Water Day coincides with the International Year of Sanitation.
Ban called on the international community to take firmer and faster steps to tackle the problem and said the flow of positive results would extend far beyond better access to clean water.
"Every dollar invested in water and sanitation yields an estimate seven dollars worth of productive activity," said Ban. "And that comes on top of the immeasurable gains in cutting poverty, improving health and raising living standards."
The secretary-general called it "unconscionable" that a child dies on average every 20 seconds because of sub-standard sanitation conditions that are preventable - a situation endured by an estimated 2.6 billion people worldwide, or more than a third of the global population.
"Poor sanitation combines with a lack of safe drinking water and inadequate hygiene to contribute to the terrible global death toll," Ban mourned. "Those who survive face diminished chances of living a healthy and productive existence. Children, especially girls, are forced to stay out of school, while hygiene-related diseases keep adults from engaging in productive work."
Over 60 percent of Africans lack access to a proper toilet, according to the United Nations World Health Organization and UN Children's Fund in a joint message for World Water Day, whose 2008 theme is Sanitation Matters.
"Sanitation is a cornerstone of public health," said Margaret Chan, WHO Director-General. "Improved sanitation contributes enormously to human health and wellbeing, especially for girls and women."
Of the 2.6 billion people without toilets in their homes, nearly 1 billion of them are children.
On March 14, the WSSCC launched the Global Sanitation Fund, the first global financing mechanism to increase expenditure on sanitation and hygiene.
WSSCC Executive Director Jon Lane stresses that the Global Sanitation Fund is demand driven and people centered. "The Global Sanitation Fund will not embark on the construction of kilometers of sewerage pipes and other huge construction projects, since top-down investments in the sanitation sector don't reach the poorest people," said Lane. "The Global Sanitation Fund will support programs that have been developed through decision-making processes involving local communities and will concentrate on hygiene education, raising awareness and creating demand."
But as projects such as one at the Shimo la Tewa jail in Mombasa, a city on the Kenyan coast, highlight that there are less costly solutions to the problem that are beneficial for other reasons, said Achim Steiner, executive director of the UN Environment Programme. In this project, inmates work with nature to neutralize human wastes by using wetland-filtered water, called "black wastewater," for irrigation and fish farming, providing a source of protein which can be consumed or sold to local markets.
Additionally, this wastewater – containing high concentrations of human waste – will also be used to produced biogas, which can be serve as fuel for cooking, heating and lighting. This could slash the costs of the 4,000 person prison and curb emissions.
The scheme in Mombasa, which is also expected to help wildlife such as birds and marine organisms, has a price tag of $25 per person served, which is significantly less than projects in developed countries, Steiner said. “It is hoped that the lessons learn can be applied to other parts of the world so that the multiple challenges of sanitation and pollution can, in part, be viewed through a nature-based lens.”