In 2012, I became heavily involved with an organization at George Mason University called Engineers for International Development (EfID). The organization's goal is to use its students' abilities to improve small communities' quality of life in developing countries. By supplying knowledge on the ground, communities are able to set up reliable infrastructure systems that support their basic physiological needs. Much of the time, this involves setting up fresh water supply systems.
The Maijuna Project
The Maijuna (pronounced my-HOON-a) are a native Amazonian people with four villages in Peru's Amazon rainforest. Once nomadic in nature, the 450 remaining Maijuna have since settled, but continue to drink unsanitized water, which has led to health issues. The children, more susceptible to malaria and other illnesses caused by poor sanitation habits and drinking unclean water, face high mortality rates.
As secretary of EfID, I was visited by the man who had worked with the Maijuna for over 15 years, Dr. Michael Gilmore. He approached us asking for help coming up with solutions to their water resources problem. As project manager for the Maijuna Project, I organized a team of engineering students, and met with faculty advisor Dr. Barry Liner and Dr. Gilmore.
The Sucusari Village, one of four communities belonging to the Maijunan.
Choosing a Sustainable Solution using Schmutzdecke
After discussing the possible solutions, we decided that a biosand filter was our best bet due to its success in countries all over the world. A biosand filter works just like an industrial sand filter - water passes through a deep layer of sand and rocks that removes particulate matter from the water. Near the first millimeter of sand lies a layer of biological growth called schmutzdecke. When the water passes through this schmutzdecke, bacteria and other disease-causing microbes are removed from the water, eliminating the need for chemicals. While further sanitation is required to get the 100% potable water required by the EPA, a biosand filter provides superior drinking water when compared to the untreated river water the Maijuna drink.
Getting Our Feet Wet
Once we got to the Amazon (the first of many South American visits we would make), we discussed the idea with Sebastian, the president of the Maijuna community. His excitement for clean water was contagious. As he escorted our team from the Maijuna community back to the city where we would catch our flight home, Sebastian suddenly ordered the boat captain to cut the engine. He went over to Dr. Gilmore and tried explaining that the sand they needed was hidden beneath the boat. After a couple minutes of conversation, Sebastian took a last look at Dr. Gilmore's puzzled expression, moved to the side of the boat, and jumped into the muddy river. With a quick gulp of air he disappeared underwater. His smiling face popped up several seconds later with a shirt full of beautiful black sand. The type of sand, as it turns out, that works just perfectly with biosand filters.
A biosand filter building lesson with the Maijunas in Peru.
A Self Sustaining Community
With quality sand in good supply, we engineered a specific design for the community. Each filter was contained in a 30-gallon food grade plastic drum that housed the filtering mediums, pipes, and pipe fittings. A perforated pipe at the bottom led to a tap coming out near the top of the barrel. Large gravel was placed around the perforated pipe and topped with smaller gravel. The sand was then poured over the gravel, and stopped several centimeters below the tap. The water pressure made the water flow through the tap, removing the need for a pump.
There are now biosand filters in each home of the Sucusari community, one of the four Maijunan communities. Every new filter was a building lesson in itself, where we guided the families through their own filters' construction. They also received a written manual outlining the construction steps and proper maintenance.
More Resourceful Than Your Average Engineer
We went back to South America one last time, just to check up on how things were going and to construct a few more filters. As we finished constructing one last filter, made right before we had to leave, we found that it just wouldn't work properly. No matter how much water we poured into it, the flow rate from the tap was unbearably slow. We tried a number of different maintenance solutions before we decided the best option would be to completely rebuild the filter from new material (a 3-4 hour venture in a time-desperate situation). As we loaded the boats to retrieve new materials, one of the community members walked over to the filter, stuck his hands inside and forcefully shook the exposed pipe. After a few spurts and air bubbles, water began to adequately flow from the tap - the bubbles had formed somewhere in the drum and the filter materials just needed a little shift. Laughing at the solution's simplicity, we left the Amazon confident that the Maijuna community had figured out the system's kinks even better than we engineers.
The Maijuna were incredibly grateful and showed their appreciation by hosting us and feeding us wild game they caught throughout our visit. Someday I'll visit my friends down in the Peruvian Amazon again, but for now I'll just remember the trip as both incredible and successful.
The difference between clean water from the biosand filter (left), and raw river water (right).