The Ultimate Gift
December 1, 2010
Water is essential to life. Yet it is estimated that more than 2.6 billion people--39 percent of the world’s population--do not have access to an improved water source.1 In under-developed regions, particularly in Asia and sub-Saharan Africa, many communities still rely on unprotected wells or springs, canals, lakes or rivers to fetch water.
Recently, an African village of approximately 1,000 residents was given the gift of a clean water resource due to the generous help of a student chapter of Engineers Without Borders USA (EWB), several professionals who functioned as mentors, and technology that made the work possible.
The project took place in the nation of Cameroon. Located in central Africa, Cameroon is often called “Africa in miniature” because of the diversity of its indigenous people. Sudanese and Fulbe reside in the north, with the Bamileke and the Bamoun to the west; the Bantu, which include Douala, Bassa, Bafia, Fangs, Boulou, Ewondo and Eton, located in the south and east; and Pygmies in the more remote forestlands.
In northwest Cameroon lies a small village called Kikoo. The people of Kikoo have historically used water from nearby streams. Situated at the bottom of large valleys, these streams are unprotected from the animal grazing, bathing and clothes-washing that occurs in the area. Not surprisingly, some of the most common illnesses in the community are waterborne, such as gastrointestinal infections and dysentery.
Through a survey and health assessment in April 2005, members of the Catholic Diocese’s Social Welfare Department from nearby Kumbo identified improved sanitation as a substantial need for the Kikoo community. They contacted EWB-USA for technical and financial assistance and have been working with the group ever since.
Quite simply, the goal for the Kikoo project was to design a gravity-fed system that features a sealed spring water-fed catchment box (which dams the water coming from a natural uncontaminated spring), a concrete storage tank that would hold the water, and a network of pipes to distribute the water to 12 publicly accessible standpipe water taps with galvanized iron faucets at prominent village sites, such as a church and a school. The Kikoo villagers would then be able to fill containers with clean, drinkable water to take back to their homes for use. Two additional standpipes would be constructed after the secondary storage tank was completed.
Accurate ElevationsIn January 2007, the EWB Yale Student Chapter (EWB-YSC) conducted a technical assessment and terrain survey of the village. The group then designed a gravity-fed water distribution system including more than 7 kilometers (4.4 miles) of pipeline, 14 standpipes and two large storage tanks located 5.5 kilometers (3.5 miles) apart. Construction was initiated by local engineers and community members. EWB-YSC traveled to Kikoo in August 2007 to assist in the construction of the main 4,500-liter (1,200-gallon) concrete storage tank.
In January 2010, EWB-YSC returned to Kikoo to aid the construction of the second 3,800-liter (1,000-gallon) storage tank, initiating the final construction phase of the project. Jeremy Smith, product specialist with Superior Instrument, Milldale, Conn., traveled with the group, bringing expertise and a crucial piece of technology--a Topcon total station with an FC-100 Topcon data collector using TopSURV software. “The Yale chapter of EWB had contacted me in their search for mentors,” he says. “From the description of the project at that point, I knew that I could help the Kikoo community and student engineers with obtaining the land survey data needed for finishing the water system.”
Dave Sacco, an engineer with TPA Design Group, New Haven, Conn., was also a mentor for the seven Yale undergraduate students who traveled to Kikoo to assist with the project. Many of the students had studied environmental engineering and fluid mechanics.
In the first two days of work in Kikoo, a team led by Smith conducted a land survey to confirm the proposed secondary tank elevation relative to the primary tank. “The elevation of this secondary tank determines whether it can be supplied by water from the main tank and which standpipes it can service, so we decided that a careful topographical survey between the two tanks was a worthy use of our time,” Smith says.
The survey work revealed that the proposed secondary tank site was 12 meters (39 feet) below the primary tank. This was a lower elevation than the one recorded on the earlier trip made by the Yale EWB team, on which the designs for the storage tank were based. However, the tank design was not changed by this new finding; at the new, lower elevation, the secondary storage tank will simply fill up at a faster rate, and the float valve should still be able to withstand the pressure of the system when the tank has reached capacity. “We were able to complete a level run from the first storage tank to the location of the new storage tank,” Smith says. “We were also able to locate most of the standpipes throughout the village and a few key buildings within the village.”
The first setup was on top of where the first water tank is located. The elevation was originally determined by a handheld GPS system since there are no surveyed bench marks within 300 miles of Kikoo. At the time, this was the only option for obtaining an elevation. “We were able to collect the standpipe’s location data with much better precision using the Topcon total station than what the handheld GPS device had shown,” Smith explains. “Once we had a point and direction, we were able to orientate our data with satellite data. Most of the satellite data for that region of the world is very crude, so we were able to obtain much better information using the total station.”
Use of the total station provided other benefits, as well. “We were also able to dig the hole for the secondary water tank more precisely, and we used the Topcon data collector to create a slight slope at the bottom of the hole for water runoff and tank drainage if ever needed,” Smith says. “Normally, this would have been done with string lines, so we saved a tremendous amount of time--especially for the masons--and we captured a more accurate representation of the village of Kikoo. Using the Topcon technology took a lot of the guesswork out of the job.”
An Effective SystemDetermining the lowest elevation in the system is important because that is where the water will reach its highest pressure. The drop from the first water tank to the lowest point was about 90 meters (295 feet). The proper placement of the tanks and the network of piping is critical for ensuring the effectiveness of the water system.
The community understands the distribution system, and the 27-person Kikoo Water Committee, chosen from members across the entire Kikoo community, is responsible for its overall management and maintenance. Everyone in the village is entitled to the water provided by the system, and the water committee has established an agreement for their water rights. In addition, each standpipe has a designated “president” who holds the key to the standpipe tap and is responsible for turning the standpipes on for a period each day so households can collect their daily water supply. The limited access to the standpipes was instituted by the water committee to ensure that all standpipe users are paying their monthly dues and to prevent water from being wasted. (When the standpipes were first installed, young children would often play with the taps and leave them running.)
Smith and his team spent two and a half weeks in Kikoo, and they accomplished their goals. “There is little, if any, professional-grade survey equipment in Cameroon, so having the Topcon equipment there helped immensely,” Smith says. “We were able to correct measurements that had been made by EWB on their 2007 visit where they had used a handheld recreational GPS unit.”
Clearly, bonds were formed between the Americans and the local Kikoo community. There is talk about maintaining contact and potentially working with a neighboring community facing a similar need. Smith concludes: “It was certainly gratifying to ensure that the village has something that we take for granted--ready access to uncontaminated water.”
For more information about Superior Instrument, visit www.superiorinstrument.com. TPA Design Group’s Web site is www.tpadesigngroup.com, and EWB’s Web site is www.ewb-usa.org.
1. WHO/UNICEF joint monitoring report 2010.