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Shedding Light on Clean Drinking Water

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Another P3 Success Story

A team of students awarded funds from the EPA's P3 Student Design for Sustainability competition is now testing their design for use in the "real world." The team from the University of California, Berkeley won a P3 Award in 2005 for their innovative, low-cost design for solving one of the world's greatest health challenges: unsafe drinking water.

While the people of the United States have nearly universal access to safe drinking water, that is not the case in much of the developing world. The World Health Organization (WHO) estimates that waterborne illnesses associated with unsafe water, sanitation, and poor hygiene lead to the deaths of some 1.7 million people annually and contribute heavily to the global burden of disease.

To help address this crisis, the U.S. Environmental Protection Agency awarded funding to the Berkeley team for their proposal to make and distribute ultraviolet (UV) light tubes to sanitize untreated or inadequately managed water. The ultraviolet (UV-C) radiation emitted from these tubes inactivates waterborne bacteria, viruses and protozoa, making the water safe for human consumption.

UV Tubes are easy to use and can be constructed from common, low-cost materials, that are readily available in developing areas. Already, they have been made by local people in Mexico for as little as $40. In contrast, centralized water treatment plants cost around $700 per family, making them prohibitively expensive for developing countries to build.

At the Environmental Engineering labs in Berkeley, the team tested the UV Tubes for the germ-killing effectiveness of the light itself, used tracer studies to ensure the water was adequately exposed as it flowed past the tubes.

Studies were undertaken with partner organizations in Haiti, Mexico, and Sri Lanka. The Haiti project is supported by Haiti Outreach: Pwoje Espwa (H.O.P.E.). A UV Tube is currently installed at H.O.P.E.'s center in Borgne, Haiti, with local visitors treating 30 to 50 gallons of water per day.

In Mexico, the team worked with two federal agencies: the Mexican Institute for Water Technology (IMTA) and the National Council for Rural Schools (CONAFE). Researchers from IMTA have validated the UV Tube according to Norma 180, the Mexican standard for household drinking water treatment. In addition to the agencies, the team worked with staff from local hardware stores and rural teachers from CONAFE to construct and install 24 household UV Tubes in two rural communities in the state of Baja California Sur, Mexico. In this pilot study, the Berkeley team monitored the efficacy of the technology in the field, as well as its user acceptance.

Motivated by the success of the pilot study and the urgent need for water treatment alternatives in the region, members of the team created a nonprofit organization called Cantaro Azul. The goal of Cantaro Azul is to promote the use of the UV Tubes and other forms of water purification technology throughout the rural communities in Mexico. Cantaro Azul has received funding support from the P3 Award, Engineers for a Sustainable World and private donations to carryout more pilot studies and to develop a strategy that will allow the UV Tubes to be disseminated on a larger scale.

In August 2005, Berkeley researchers traveled to Sri Lanka to develop and test a family-shared version of the UV Tube. As part of the program, four technical officers from Sarvodaya, a Sri Lankan development organization, were trained to construct the UV Tubes. The technical officers have subsequently installed eleven systems in two rural villages serving 140 families, one preschool and a train station.

Real World Learning
In addition to actively promoting sustainability in the developing countries where they have the most practical application, the UV Tubes are also proving to be a valuable learning tool at Berkeley. Students are using the technology and this project to confront global development issues and as a bridge to explore environmental, economic, and cultural sustainability.

A half-day UV Tube "Brainstorm and Build" workshop was held at Berkeley in January 2005. During the workshop, 18 participants studied UV water disinfection and the issues related to its implementation in developing countries. Then, they worked together in "brainstorming and build" sessions to design and construct new UV Tube designs. The workshop resulted in innovative design ideas that were later implemented in the field, improvements to the construction manual, additional team members-and a lot of enthusiasm!

Successes and Challenges
A number of successes and challenges have been encountered. The UV Tubes have been found to provide consistently safe drinking water at a rate of five liters per minute (5 L/min)(1.3 G/min). At UCB, the team has fostered the process of student-led curriculum development for a Sustainability and Appropriate Technology class. The class is currently being offered as a technical elective for engineering students and some of its students are already planning to work on the UV Tube projects in Mexico this summer.

The UCB team has succeeded in their work to combine aspects of people, prosperity and planet into a workable model that will have tangible benefits. Safer drinking water is one of the basic necessities of life, and this team has developed a tool that can deliver this vital resource in a low-cost, sustainable way.

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