Our project is to provide safe drinking water for the village of Cuchiverachi which resides in the mountains of western Mexico. The people are part of an indigenous tribe known as the Tarahumara. In the 1600’s, the Spaniards arrived in search of gold and silver, as well as to bring Christianity by the Jesuit missionaries to the Tarahumara. The Jesuit era lasted until 1767 when the Tarahumara were expelled from Mexico by Spain. The Tarahumara were pushed westward into less desirable mountain lands out of the main lands of the state of Chihuahua and were mostly left alone by the government. Contact was minimized. They have a unique style of clothing that is very colorful and beautiful. They travel almost completely by foot and are renowned for their long distance running capabilities.
A nearby hospital has reported many cases of illnesses in this region caused by tainted drinking water and has concern for their sanitary practices (as there are no human waste systems in place). There are a number of natural springs and small streams in the surrounding hills that provide them with water, but the water is often tainted by animals and organisms. They raise a significant number of livestock which, especially during the dry season, seek out these water sources and contribute to the contamination problems.
Our group had a unique opportunity to visit the community and was able to interact with the community and scope out the landscape. We discovered a number of springs in the hills surrounding the valley which could be used as water sources for the people. While down there, we took water samples of each of these springs and found that the ponds where the water collects are unsafe to drink. However, upon digging down to the eye of the spring we found that the water is completely safe, clean and good to drink.
During our spring semester, we will be developing maps of the area and designing a water distribution network to provide drinking water to their homes, school, and new dormitory. The design will include catchment systems, piping, filters, valves, and storage tanks. We have decided to go with a gravity based system as it simplifies and extends the life of the system having no moving parts.
The Tarahumarans have a unique culture and lifestyle, seemingly untouched by modern civilization. In our project description, we state that our goal is to improve their quality of life. This term can often be misinterpreted and ill-defined. Our team has discussed and debated what it really means to improve the quality of life. Does a more modernized life style mean an improved quality of life? Does having more material things produce an improved quality of life? What about longevity (long life)?
Upon wrestling with these tough questions, we concluded that water is the most essential element for life and that as images of God, all people at least deserve access to clean drinking water and be educated about proper waste disposal. Our hope is that these changes will decrease the number of illnesses such as chronic diarrhea. We know that this could have substantial effects on their community, for example decreased mortality rate which could lead to an increase in population which could put strain the current food system or have a number of outcomes. All this considered, we believe that providing them with clean drinking water will improve their quality of life through reducing illness and allowing them to live as God intended.
Cultural sensitivity and appropriate technologies are important components that we are not only taking into consideration, but designing our project around them.
We believe that God has called us to this project to improve their quality of life through blessing them with an essential element: Water For Life (Agua Para Vivir).
Our team has analyzed various alternatives for supplying water to the dormitory and for improving health and hygiene practices. Through our research, testing, and decision process the following is a brief overview of what the final design consists of.
Water will be supplied from a spring located approximately 1.5 kilometers to the north east of the dorm at an elevation of 98 meters above the dorm. The spring is currently surrounded by a barbed wire fence to prevent animals from becoming stuck in the thick mud. An area of 180 square meters, 13.5 meters by 13.5 meters is saturated with water all year round. Due to the large area of saturated ground, an accurate flow rate could not be taken. The soils are mostly clay, which form a thick mud when disturbed. Due to the large area, the exact location of the eye of the spring could not be determined. Each component will be described below. The following figure gives an overview of the water supply system to the dorm and the components found at the dorm.
The spring catchment system is two 15' drainage pipes buried a few feet under ground downstream of the eye. The pipes will be buried under very permeable gravels and sand to promote infiltration into the drainage pipe.
From there, the water will be conveyed through a 3" pipe to the settling tank. In the settling tank, particles with a diameter greater than 0.001 cm will settle out (requiring routine maintenance for cleaning).
The water will then be further conveyed (1" pipe) to a storage tank. The storage tank will be ferrocement (chicken wire, rebar, and a finer aggregate concrete). Our calculations put the storage tank at about 100 ft above the dorm (several hundred meters up the hill to the north east), which should provide an adequate pressure of approximately 40 psi. Also, the storage tank should be able to hold over 5,000 Liters, which is enough contingency for a few days of heavy water use at the dorm.
From here the water will be conveyed to the dorm. At the tap, water will not be purified. Even though spring water is a relatively clean source of water, there are multiple ways the water could become contaminated (e.g. animals get into the catchment, kids get into the tank or settling box, the system is not properly maintained, etc.). To be conservative, we recommend purification of water that will be consumed (cooking and drinking water). Most of the water demand at the dormitory will go to showers and toilets, thus we thought it would be more efficient and economical to treat only drinking and cooking water. This purification includes: filtration using the CAWST concrete biosand filter, and disinfection using a granular calcium hypochlorite bleach solution.
To promote showering, it is recommended that a hot water system be implemented. This hot water system is comprised of two parts: a solar heating panel (copper tubing inside a glass panel) with a small circulating pump, and a wood fired boiler.
A rain water collection system will be used for irrigation of the community vegetable gardens and fruit trees. This design consists of gutters leading to four 1,100 Liter tanks. These tanks can be used for irrigation, but we also recommend that one tank be used as an emergency supply of water (that tank should be alternated to keep the water relatively fresh).
The final design component is for latrine pits. Latrine pits should help reduce the "fecal to mouth transport" by reducing human contact with feces. These pits are essentially outhouses, with a lightweight superstructure (wood) and a concrete lined block pit. Our goal is for each family in the community to eventually have a latrine pit. An overview of the implementation of a latrine pit can be seen in the following figure.
Please click on the link that corresponds to the specific design component of your interest: