Simple Solution for a Serious Problem
In March 2005, two students from Nerinx Hall High School in Webster Groves, Missouri made a service trip to the small town of La Chinantla, Mexico. There they learned first hand that something that most of us take for granted - easily accessible clean water - is simply unavailable to many people in poor rural areas. In La Chinantla, women and children spend much of their time hauling water from distant wells. The water itself is contaminated with farm waste and tests positive for fecal coliform (E. coli) bacteria. This problem is not confined to rural Mexico:
Because it is traditionally "women's work" in many cultures, women and girls spend much of their day collecting and carrying water for their families. In fact, the World Health Organization (WHO) estimates that African women and children spend up to 6 hours per day or 40 billion hours collecting water every year. Hauling water is physically taxing as well. The most common way to carry water is in 20L (5 gallon) jugs that weigh 20 kg (44 lbs.). Girls and women who regularly haul this heavy load commonly develop serious back, hip, and pelvic injuries.Back in Missouri, a team of 10 young women*, all seniors at Nerinx Hall, developed a relatively simple device to address this problem: filters in a barrel on wheels. To fund the project, the team received a $7,800 grant from Lemelson-MIT InvenTeams, a program that helps high school students develop their inventions. The beauty of their invention is that it can be made with components readily available in towns like La Chinantla.
Often the water that has taken many hours to haul is dirty–contaminated with pathogens and other pollutants. According to UNICEF and WHO, 1.1 billion people living in developing countries around the world drink water that is unclean. This results in about 4 billion cases of diarrhea every year, half of these cases resulting in death and 90% of deaths are of children under five years old. Water-borne pathogens also cause other widespread diseases such as typhoid and cholera. It is these women and children that will benefit directly from our invention.
One unit consists of nine filters made of:
- sand to filter out organic debris
- carbon - which could be made from charred nut shells - to improve color, odor and taste
- a ceramic cup to remove pathogens. This is very cleverly made by mixing clay, water and coffee grounds, which is poured into a mold (the shape of a half coconut shell) and fired. Firing burns the coffee grounds away, leaving pores small enough to catch bacteria, but large enough let the water through.
A single barrel is large enough to hold a day's supply of water for seven people and can remove 95% of contaminating E. coli . They are now working to further improve the filters using locally available components.
Such inventions - both practical and simple enough for local manufacture - have the potential for promoting social change. Not only would the availability of clean water improve the overall health of the population, but would also reduce the amount of time spent transporting water, allowing, for example, more children to attend school.
Kudos go to high school seniors Katy Adkins, Erin Burton, Lydia Caldwell, Molly Fitzgerald, Mary Kate Hogan, Danielle Jaegers, Katie Kollef, Liz O’Brien, Taylor Reifsteck and Nicki Shamel for work that has the potential to positively affect the lives of many people!
* The student team had advice and assistance from Peace Corps volunteers, wastewater treatment experts, and engineers.
Tags: science education, invention, water purification