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Alex,

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 are reasonably confident that you have the potential for one proper water supply borehole; completing the exploration borehole as a proper water supply borehole, or drilling a new production borehole near the successful exploration borehole; testing the borehole as a hydraulic structure, and testing (stressing in a controlled way) the aquifer / groundwater flow system; interpreting your results; assessing from other wells, nearby, the seasonal rise and fall of the groundwater levels; deciding on the basis of the minimum static water level and the water level drawdown during pumping, the correct position for a pump intake (categorically, it is not at the bottom of the hole as is often thought); choosing, as Jeff says, an appropriate pump that fits the needs and agreement of the people; installing the pump and plinth and headworks designed for the people (and livestock) and groundwater protection; commissioning the borehole and pump; and handing over the successful borehole plus reports, borehole logs, construction diagrams, pump maintenance manuals and tools. The above is a summary. It is a long process, that requires training, skill, and experience.

As Jeff says, you need to do work before you embark on drilling.

Sometimes the technical side (drilling and pumps) of groundwater development is the 'easy bit'. It is the 'people bit' - working with the people until they and you are happy that you, together, can do something that they can use comfortably, is the 'hard bit'. Creating something for which they can take responsibility, use, protect and maintain involves a variety of skills not commonly taught at college. Being a ‘listening engineer or hydrogeologist’ sitting on the ground, listening, questioning and observing is difficult, but essential. Listening is probably more important than telling people what to do. You will be surprised at what you find out, and you will learn a lot from the people who live in the area.

Billions of pounds have been spent on technical solutions to, what were perceived as, water supply shortages in rural Africa. Most of these solutions are not in use. There are thousands of dead, defunct, disused, broken, abandoned boreholes and wells across the 'water short areas' of Africa. In 1992 the World Bank estimated that over 8 billion dollars had been ‘blown’ on misconceived rural water supply projects, which were since disused, across just the Sahel, since the 1950s.

A lot of money spent, and surprisingly few lessons learnt.

We used to think these failures were the result of technical/scientific problems. Because we were looking for a technical problem, we would often find a problem, and then we'd find a technical solution (that's what we are trained to do, and believe is our role), but after a while our new technical solutions were, like the others, still not used. What, we failed to do was... understand the people, and their capacity to accept and use something new. For example, it is not uncommon for people to reject a new water supply simply because they can't cope with the responsibility, and it ties them down to a place or piece of infrastructure. Sometimes people decide after the event to sabotage a good water supply because they realised that it had attracted their neighbours, and their neighbours' animals were eating the pastures or crops near the new water supply, and introducing diseases to the well owners’ livestock.

As I said the purely technical side of water well drilling is often easy by comparison.

Jeff is right in suggesting that you might consider options, such as wide diameter dug wells, from which anyone can lift water. There are many design considerations when constructing a dug well and most are in books but there are others rarely mentioned such as for example, parapet heights around the top of the well, so that children can get water for animals or home, but the parapets are still sufficiently high that the children can brace themselves, when butted from behind by a thirsty animal. A design element that you should consider is a galvanised steel tripod over a wide diameter dug well with bobbins (pulley) on cross bars so that women with small children, wrapped on their backs, do not have to bend over the well - fishing babies out of wells is distressing. Consider concrete walls with stile entrances so that people can get to the well, or even the borehole and a hand-pump, without animals getting close to the well. You can make troughs that go out through the walls for watering animals a few metres away from the wellhead. Think of an air supply down to the well diggers; they can die from the build up of CO2, which can arise for a variety of reasons, including the metabolism of bacteria down the well

There is quite a lot to consider and deal with.

I suggest that the fastest way of learning from the experience, would be to employ a professional hydrogeologist (with the right experience) who could lead you up the learning curve, catch problems before, they arise and see the project to a successful conclusion.

Doing it yourself, without guidance on site, will be a valuable learning experience for you all, but you could find yourselves letting down the people with whom you are working, and also following the misconceptions of the past.

As it is a student project, could I suggest that you team up with the MSc students doing hydrogeology/groundwater engineering in London, Newcastle, or Birmingham.

You might find that you get a hydrogeologist with good drilling experience to come along with his students. (A word of warning: not all hydrogeologists/groundwater engineers, in consultancies, universities, state bodies or water companies know how to do all the work summarised above. Many of them are very experienced and excellent in modelling or contaminated land, but have no real hands-on experience of water well drilling, or well digging in Africa – don’t be afraid to be discriminating when choosing an expert - regardless of the number of letters and titles after their names)

Good luck with the project. You can probably get contact numbers from RedR, if you need to talk to someone on the phone.

David