The village of al-Zafen was chosen as the site for a pilot project by the Social Fund for Development to test the efficacy of the clay filters. The results have been promising. The filters are comprised of a clay pot set inside a plastic bucket with a nozzle at the bottom of it. All one has to do is pour water, no matter how dirty, into the clay pot and wait for the clean drinking water to drip into the plastic bucket. As it drips it is exposed to the disinfecting silver that saturates the pot. The silver, which presents no health risks in such miniscule amounts, kills off 99.89 percent of the microbes that live in the water. Toxins are filtered by the clay and the resultant water ends up being cleaner than the average bottle of water. Even in test runs where sewage water was used, the resultant water was clean and drinkable. Skeptics often have trouble getting past the filter’s rudimentary appearance, but its simple design belies its potentially life-saving properties.
Tariq al-Zafeni was a skeptic when the Social Fund workers gave him a silver filter in 2008. “It didn’t run on electricity, it’s made out of clay, you don’t have to change anything inside of it. I thought this would be worthless. But I know now that it is like a gift from God. It’s the simplest thing, you don’t even have to clean it everyday.”
Its simplicity and effectiveness are its strength, and Yemen’s development community has started to take notice. Garreth Richards, the general manager of Care International Yemen, provided his testimonial: “The silver filters present development workers with the ideal water purification system. It’s simple enough that anyone can be taught how to use it, and it’s proven to be effective. There are no risks like chlorination which, when used incorrectly, is at best ineffective, and at worst poisonous. When Care deals with projects that involve drinking water, we use and will probably continue to use Rich Boni’s filters.”
In fact, Care is not the only organization taking note. The UNHCR uses thousands of the silver filters in their refugee camps. The Islamic Relief and the Red Cross also purchased thousands when Hadhramaut was struck by floods in 2008. A fully decentralized water purification system is saving thousands of people from the agony of gastrointestinal disease, as well as the thousands of rials a month spent on medical attention, and it all happened by the virtue of a happy accident.
Michael Klinger, the former country director of the GTZ in Yemen, built a kiln with the intention of making clay irrigation equipment, the market for which proved to be too small. The kiln sat there until it was realized that they could cheaply fire silver filters. The idea came from an American NGO called Potter Without Borders, which has been the biggest driver in spreading the filters around the world. After simply providing a training program to Boni and his potters, they left the company to develop independently. Richard Boni was working on the filters from the beginning. “We started with only a couple of hundred misshapen blobs of clay. Slowly we started to streamline our method, and perfect our product. Now, we quite easily bang out a thousand a month.” Under the auspices of Boni, the company has grown to its current level. Through his incredible attention to detail, he has made a product that is trusted by the development community. And attention to detail is one of Boni’s strongest assets.
Yemen Today - Silver Filters: Providing Clean Water to All
Nice try though. 
