Supplementary Water Distribution System for Roovisem and Ndzen Zui Quarters, Nkuv,
Cameroon, West AfricaCar
Joel Blok
A modified concept for Ndzen Zui. Note the parallel lines running from the current tank.
Refer to the following pages for more detailed concept development.
The pipe-laying process. PVC pipe segments (6 m each) are used; the line is buried in a trench
roughly 0.5 m underground
Summary
Nkuv, Cameroon is a remote farming community of roughly 500 residents. The
community lacks access to even the most basic infrastructure; the nearest city, Kumbo, is
accessible only by an extremely poorly maintained road. Of particular concern is the
community’s lack of access to safe drinking water; residents rely on streams that flow yearround,
but are severely contaminated. Hope College’s student chapter of Engineers Without
Borders has been working in the community since late 2005.
The water problem in Nkuv is multifaceted; the issues of both water quality and
quantity must be addressed. EWB-Hope has previously implemented filtration solutions on an
individual level in the form of Manz BioSand filters. However, as water collection takes an
average of 5-20 minutes per arduous round-trip, a gravity-fed water distribution system is
required. EWB-Hope travel teams implemented the first phase of the system on trips in 2008
and 2009 by constructing a diversion dam and intake structure in a local stream, a water
storage reservoir, and over two miles of pipeline with nine tap-stands. The initial phase,
however, only services Tankuv and Rosang, two of Nkuv’s four neighborhoods. The other
two quarters, Ndzen Zui and Roovisem, will need a supplementary distribution system to
provide them with access to source water. The design of that system is discussed in this
report.
Nkuv’s location and geography present several unique challenges that affected the
requirements of this design. Given its remote location, the design needed to rely on locally
available materials and services. In addition, the sustainability of the design was to be held
paramount; this meant that the system needed to be easy to construct, maintain, and adapt.
Finally, system efficiency had to be maximized while costs were minimized.
In May 2009, GPS coordinates of the location of each house in Ndzen Zui and
Roovisem were collected; several alternative sources were also identified. These data points
were then coordinated with an AutoCAD model of the region. This information was used to
develop ten concepts to address the design problem; each concept used a different
combination of source and pipeline configurations.
Once the concepts had been developed, full hydraulic grade line analyses were
performed on each to determine its practicality and degree of efficiency. It was determined
that none of the ten initial concepts was feasible in its original configuration. However, each
concept had one or more components that were demonstrated to be efficiently designed.
These components were then combined into a set of three modified concepts for Ndzen Zui
and two additional single lines for Roovisem and a central area of the community
infrastructure that were all shown to be both practical and efficient.
The proposed designs will all utilize a combination of PVC and galvanized pipe, along
with the necessary concrete and plumbing materials required for construction of intake
structures, tanks, and tap-stands.
These concepts will be presented in May 2010 to the residents of Nkuv, at which point
the community will select design elements for implementation in 2010 and 2011. This report
details the concept development and modification, the analysis process and results, and cost
assessment of each of the final concepts. These concepts will ultimately be prepared on Dsized
layout drawings that contain all relevant information and will be brought into the field to
assist in presentation for review and selection by the community, in future assessment of the
area, and ultimately, in implementation of the next and final phases of the water distribution
system for Nkuv.