Installing hand-pumps in rural eastern Cameroon
Dear RedR Experts,
I am writing on behalf of Cameroon Catalyst - a charity run by civil engineering students at the University of Southampton. For the past five years, we have fundraised, designed and built a number of community infrastructure projects in eastern Cameroon, including a health centre, primary school, solar hub and carpentry workshop with the idea that students use the skills they have learned on their course to provide the catalyst to further development in the region.
This year, we plan to construct three new hand-pumps (either Bluepumps, Afridev or India Mk IIs) to provide water to up to 1000 people. We still need a lot more information on the preliminary steps before drilling a borehole and building a pump, such as whether there are geological records readily available for the area or the steps that would need to be taken to investigate the available aquifers, or whether preliminary boreholes would need to be drilled and the correct methods of doing so. Any information in this regard would be much appreciated.
Many thanks for your time,
I endorse what Jeff has written above.
I may have misunderstood the stage of your project. I am assuming that when you talk about ‘constructing three new hand-pumps’ you actually meaning constructing three new groundwater supply borehole sources, into which you intend to install hand pumps.
I do not wish to daunt you, or your fellow students. I am keen to support engineers and hydrogeologists carrying out groundwater supply development work in rural areas. However, many people have an idea that a new water supply is a good thing, and that it is relatively easy and straight forward to make a hole in the ground, get water, and put a pump in the hole.
As you are probably gathering from your background research, there is more involved if you want to do the work well and properly.
The following is going to be a long sentence, but in summary ‘constructing a new groundwater supply borehole as a new water source’ is likely to involve: - carrying out a hydrogeological assessment of prospective sites (this includes assessing pollution potential risks as well as trying to find a suitable site where you are likely to find a sustainable supply of high quality water); liaising and discussing various technical options with the people who are going to use the borehole/well (they will already have a water supply – therefore you need to make sure that they can take responsibility, and will be able to use, a new one); choosing the sites; setting up drilling contracts (which would include visiting a site where the driller is already working in order to assess the range and quality of their equipment and watch while they work to assess their skills); obtaining, and supplying to the site, sufficient materials (e.g. steel casing, PVC casing and perhaps PVC well screen, cement) to provide you with design and construction options during the drilling (things happen and change quickly and drilling rigs cost money if they are idle on 'waiting time' waiting for materials. There is a Golden Rule with drilling in rural areas "It is always better to be looking at it... rather than looking for it"); designing the first exploration borehole; drilling the first hole; modifying the design in the light of your findings as they arise on site during the drilling (i.e. you need to have a hydrogeologist, or at least a geologist, on-site full-time throughout the drilling in order using their conceptual model of the geology and groundwater system that you are hoping to exploit, interpret the drill-cuttings, sudden loss of circulation, change of water colour etc. and make decisions in the light of real evidence with the driller. You have to be able to make quick decisions because you could be drilling down at the rate of a metre a minute. You have to be confident enough to tell the driller to stop and check things out as soon as you see something unusual or with potential); continuing to drill holes until you ... (more)
David's answer is excellent.
The only thing I would add is that, from WaterAid's survey of previous boreholes and pumps installed, and seeing that a large proportion of them don't work after just a few years, we can quite confidently say that water points managed by communities alone have a high probability of failing, unless there is external support from authorities / water regulators / water providers. It is a bit more detailed in our sustainability framework.
It shouldn't discourage you from promoting better water supply, but please consider technical issues and community issues as highlighted by David, and how it fits in public plans and support.
I'm not aware of any source of geological records for Cameroon, but any that exist are unlikely to be finely-detailed. The advantage of boring rather than digging a well, is that it is relatively cheap to abandon a bore that hits hard rock and try again elsewhere. The downside is that pump failure in a borehole means no supply for days or weeks. Ideally, a community needs:
- either multiple boreholes for diversity
- or a dug well with both pump and a windlass, rope and bucket within a locked well-housing for back-up - if a universal pump stand is set in the cover slab, the pump can be retrofitted
I agree with David that Cameroon is littered with wells that ceased to function within months of installation. Sometimes it's simply because the well was dug or bored in a wet season instead of a dry season. Frequently it's because the pump failed and was not repaired. Imprecise adjustment of pump rod length is a frequent but frequently-unrecognised cause of breakdown.
You therefore need community (or possibly fair-trading entrepreneurial) buy-in and a programme of ongoing support to deliver a sustainable solution and avoid wasting resources. Not only does a community need access to spare parts in a country without a reliable postal service, but also to sufficiently trained and experienced technicians, of whom there are extremely few.
The AfriDev is VLOM, but it has historically had problems – see http://wedc.lboro.ac.uk/resources/con.... It uses $1 neoprene piston seals that cannot easily be made locally. If they are not imported and distributed locally, their failure renders the pump unusable when they wear out, typically after a year. A bottom support system helps to extend the life of the riser pipe.
The India Mk2 is not VLOM, as personnel require thorough training to lift the riser pipe correctly and safely for cylinder maintenance. However, the India Mk3 is VLOM.
As of 2013, an agent had been appointed for the BluePump in Cameroon, but I was told that it would not be economic to import anything less than half a container-load, so there was zero infrastructure for acquiring or maintaining a BluePump. The BluePump is also not VLOM. While the shift to stainless steel piston rings has undoubtedly increased MTBF, like any machine, the pump is not maintenance free, despite being promoted as such.
Remember also that it takes days to travel distances that take hours to travel in the UK! If you are unlucky, the aircon in your bus may consist of it having no windows. Some sort of lightweight scarf will give you some protection from sampling the geology of a dirt road in Cameroon with your lungs!
Hi Alex, I think you can obtain all the data you need from the Institute of Geological and mining research of Cameroon. IRGM cameroun. I know of a hydrogeologist who is capable of doing the work. His name is Dr Richard Ayuk Akoachere, Lecturer of University of Buea, Cameroon. you can reach him using firstname.lastname@example.org. He has over 25 years of experience in community water projects and is the biggest name i know capable of carrying out what Jeff suggested.
Address P.O. Box 4110 Nlongkak City Yaounde Phone +237 2422 2430/2441
Is there a voting system for best message? I think David Ball's message just got my vote! What a belter!
Dear Alex, you may want to look here at the CanZee pump and talk to Richard Cansdale of SWS Filtration up in Morpeth about the CanZee pump and about well-jetting which is a cheap and relatively easy way of effectively making a shallow bore hole. http://www.rural-water-supply.net/en/... and http://www.swsfilt.co.uk/nzp/index.htm
Eric Fewster of Bushproof lives in Greater Manchester so is easy to get hold of and is well known at RedR UK: http://www.bushproof.com/about/shareh...
Judging from what several respondents have said above, it sounds as if boreholes are fraught with problems in Cameroon. So depending on the strata, level of the water table and water quality it may be better to preferably treat whatever water is available to render it potable or to establish shallow boreholes and use a CanZee pump provided the strata and water at the levels suiting the pumps and well jetting is potable or good enough to simply run through a sand filter.
All the best with your projects. Power to your elbows and brains in equal measure!
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