Tanner Goff and Dr. Bruce Woolley, Department of Physiology and Development Biology

In Sub-Saharan African countries the resource of most significance, we Americans take for granted: water. The African people know this and strive to minimize wasting such a precious resource. However, with little education on how to conserve water, waste is inevitable. The country of Cape Verde is no stranger to a huge water deficit and this water deficit has a direct effect on the diet of the people. Most of the country relies on beans and rice with no variety of vegetables in their diet. The typical Cape Verdeans diet is characterized by “repeated rice meals” and “as the water prices rise due to extreme lack, so do the demands to balance household expenses which reduces the ability to purchase nutritious foods” (Rodrigues 365). With a small amount of education on how to conserve and /or re-use water, the Cape Verdeans diet can be altered to include a variety of vegetables and offer better nutrition.

The largest waste of water that we knew could be saved came from used laundry water. The people of Cape Verde often wash their clothes in 15-20 gallon tubs. Once the water has been used for a few loads of laundry, it is tossed out into the streets to evaporate. If this greywater could be re-used to water plants in an efficient garden system we could easily increase the variety in their diets. We began our project by finding the most effective way to use the trash from the streets. We wanted to both re-use the water and the trash to teach the people how to make a portable water efficient garden. We found two ways to do this: a water filter and a bucket garden system.

The Filter & Bucket System

The easiest way to filter laundry water enough to water plants without damaging the roots was to use a slow silt filter. These filters essentially act like the earth does— as water trickles through the layers of the earth the bad particles are caught in the different sediment layers. Our filter was composed of two large 5-liter bottles. They filled from the bottom up with an inch of pebbles, a thin cloth, an inch of crushed carbon, another cloth, and about 6 inches of sand taken from the local beach or desert. The soapy laundry water is run through this once or twice and then used to fill the water reservoir in the bucket.

The bucket system was also constructed using trash found in the streets of Cape Verde. The “Two Bucket System” is not a new idea pioneered by us, but has been used in many arid areas to increase water efficiency in home gardens. In Cape Verde the 2 biggest problems are water and space. The bucket system allows families to conserve about 80% of the water they would normally use for the same vegetable garden and it allows them to grow gardens on top of their concrete roofs.

The system is constructed of two large five gallon buckets, a juice box and a PVC pipe (all trash). The top bucket holds the soil and has a large 3-inch hole through the center, a 1-inch hole against the wall, and many 1⁄4-inch holes throughout the bottom. This top bucket is stacked on top of another bucket. The stacking allows for a space between the buckets that will act as a water reservoir. The 3-inch hole in the top bucket houses a large juice box that has fenestrations in the side to allow water to seep in. The soil is then packed into the juice box which hangs down into the water reservoir. The water seeps into the soil and then acts like a sponge to suck the water toward the roots. Soil is then placed in the top bucket, almost to the brim. The 1-inch hole is for a PVC pipe which will fill the reservoir when it runs out. This bucket system is more efficient because the water does not evaporate out of the bottom reservoir as it would if the plant was watered in a traditional way. Also, eventually the roots grow into the reservoir through the 1⁄4- inch holes and can take what they need, consequently, there is no under or overwatering.

Cape Verde

Once we had done enough research and established what we were going to do in Africa, we traveled to Cape Verde in May of 2010 with the hope of teaching people how to build water efficient gardens. If properly applied, we knew our idea would both save them money and fortify their diet with more nutrients. We focused our efforts on four specific cities: Tarrafal, Praia, and Mindelo, and the small island of Sal. In order to get our information to the most people in the shortest amount of time, we gathered groups together at churches. In each of these cities, we taught them how to construct both the filter and the bucket gardens. We talked to over 300 people about how this could save them money and help their diet. We also made a small brochure with specific instructions on how to build the filter and the bucket system.

After we had shown the people how to construct the two systems we went to many houses to help them build their own bucket systems and filters, and made sure that they understood the information well. We also visited some of the local schools to teach students and teachers how to build the systems (Fig 2). The local teachers were preparing for a science carnival for the following week and they said they would re-teach the students to make sure that everyone understood how it worked.

Conclusion

Overall our project was a bigger success than we had ever imagined. We were able to teach over 400 people about how to improve their diet and conserve water. A few people since have e- mailed us describing the results they have had from managing their own buckets. We have plans to return to this area and continue to spread our idea so that more people will have the chance to have a healthy diet. We believe that the youth of Africa are the only way that we can have a lasting influence. In future trips we will focus on junior high and high school-aged students. Our future goals are to have a secondary school integrate our method as a hypothesis based study so we can not only encourage innovative thinking, but also promote greater health and water conservation awareness. The more we inspire these children to think, the more they will begin to surprise us with their abilities.