University of Arkansas, Fayetteville


Access to drinking water is essential to all life, yet in many developing and remote communities, it is often contaminated with disease causing pathogens. This project was created in response to the annual WERC Environmental Design Competition. This year’s specific challenge was to develop human powered, stand-alone, effective, easily implemented, and economical water disinfection systems. Many technologies were evaluated; however, bleach and ultraviolet (UV) light treatments were determined to be most applicable to remote and impoverished communities. The Razorback Microcide WERC Crew designed and demonstrated two systems independently featuring bleach and UV disinfection technology. Both systems include a high capacity, human powered treadle pump which sustainably operates at 15 gpm. The bleach system, which operates using only human power, treats 3,000 gallons of water in five hours. The UV system treats 3,000 gallons of water in 9 hours using solar power. Both systems can be assembled in remote locations, can be operable in five days, and are portable via light truck. The first cost of the UV system is $1,485 and the operating cost is $0.002 per gallon. The first cost of the bleach system is $550 and the operating cost is $0.001 per gallon. The bleach system is advantageous because it has lower costs, uses only human energy, and requires fewer specialized parts, while still delivering an EPA recommended disinfection. The UV technology is a feasible alternative that does not add chemicals to the water. The Razorback Crew made arrangements to implement the project in Haiti, but were prevented from doing so because of government travel restrictions.