(with special reference to handpumps in very deep boreholes)
The so called Standard or "Public Domain" designs can be produced by any company in any country. A drawback however is, that several "killer" spare parts (like some nylon and rubber parts, unfortunately also the most important recurrent spare parts) are very difficult to produce, so in most cases still need to be imported from countries like India, that could produce handpump high quantities for low prices. As a result, 100 % local production of public domain handpumps never really could develop in Africa and the most important spare parts became very expensive or were not available at all. From various sources it also became clear that, in spite of the original idea of a standard handpump with uniform quality, there seems to be an important difference in quality between one producer and the other. It was mentioned that this was mainly due to the fact that price was more important than quality control.
The Volanta design is different from the traditional handpump and based on a traditional Portuguese village watersupply flywheel handpump (still in use in Portugal, some in Mozambique, Angola and Guinea-Bissau) to supply reliable water for a village from a dugwell (at that time boreholes were not in use for village water supply). For sanitary reasons it was import to cover the many open dugwell in the villages, so this Portuguese flywheel pump was put on the well cover, pumping the water to a public “Fontenario” near the well.
The Dutch Volanta design is also based on the VLOM principle, but with more emphasis that most of the current spare parts should be non-specific to the Volanta design. Spare parts should be materials (grease, standard bearings, pressure rings, etc.) also locally in use for other purposes and therefor be available on the local market and users are not dependent on original parts supply from Holland. The original Volanta design aimed at an installation depth of 50 m. This is already deeper than the more “traditional” handpump design; the Volanta therefore uses stronger materials (especially those parts that are subject to wear) and also has a maintenance free stainless steel piston concept (like no pressure segments).
The experience in the field showed, that all handpumps have more breakdowns with increasing depth and number of different users,. However, the Volanta’s performed outstanding good for these depth up to 50 m. With this experience in mind, many project start to use Volanta’s also for deeper water levels, even up to 100m (field experience from thousands of Volanta’s in Niger and Burkina Faso).
The initial experience to use Volanta’s for deeper settings was positive, although the pumping becomes more heavy with increasing depth, the pumps performed without problems. However, after several years (about 2 to 5 years, depending on depth and number of users), the Volanta’s also suffered from breakdowns, due to breaking of the sockets, that connect one PVC pipe to the other. After a study in 1996, it became clear that these problems were mainly due to fatigue in the PVC, caused by the concentration of vibrations in the PVC sockets, on the end of the pipes. In combination with the weights of the PVC pipes and the water column inside this caused the rising main to break. These destructive vibrations were especially frequent is deep boreholes with diameters larger than 4”. Proposed remedial procedures for this were:
· Vibration can be limited (not avoided) by applying stabilisers on the rising main, made from locally available materials like borehole casings, which will extends the lifetime of the joints, but occasional repairs (between 5 or 10 years) probably still remains necessary.
· Stretching can be limited, by strengthening the middle part of the PVC, by applying oversize PVC in the middle or simply cutting them in half and applying sockets on the middle part. Also PVC repairs should be made like this, so the PVC pipes should always be cut half way and not close to the old socket, to strenghten the pipe.
· Ungluing can be avoided by applying a new larger “zero-fit” sockets for this depth and applying the recommended gluing procedures.
From various sources (NGO’s, distributors and users in several countries) it became clear that the performance of the standard handpump deeper than 40 m. is far below the designed performance standards in term of breakdowns and easy to repair. When NGO's started to use the cheaper standard handpumps in deep groundwater zones, this results for the users in:
· Considerable higher operation costs and
· Inconvenience in terms of interrupted availability of water and finally in
· Many handpumps permanent broken down without repair.
At the same time, it could not be indicated that due to the relatively increase in demand for spare parts in these zones, a natural flow of spare parts was coming up through the private sector. However, this could also be influenced by the large amount of spare parts still available on the informal market, often from left over stocks from many NGO projects.
In countries were Volanta were used in the “Volanta zone with deep groundwater” also the Volanta users experienced a strong negative impact of the NGO policy of starting to use the cheaper standard handpumps in deeper zones: Because the number of Volanta’s the Volanta zones was not increasing, but relatively decreasing, the motivation for local individuals or shops to keep or to start selling spare parts for Volanta decreased. The initial available spare parts from the projects were often not replaced, as there was no profit incentive to investment in this small market.
Any equipment will, sooner or later, need a form of maintenance and repair attention and so also handpumps will need sooner or later looking after by someone.
Therefore, that the main reason for the non-repairs of handpumps is not due to only technical problems. In Niger for instance, about 95 % of over 1000 Volanta’s are working, of which about 75 % deeper than 40 m. (even up to 110 m deep). In case of occasionally breakdowns, the local distributor gives privatised support on request to local maintenance groups or individuals for repairs; all repairs are paid for on a commercial base.
However, often Projects handpumps have been donated and installed without paying enough attention to an adequate O&M and spare part distribution system. With this experience of Volanta O&M in Niger in mind, we therefore believe that for most of the present non-working handpumps in deep groundwater zones, the main solution is not only to introduce some (important) technical improvements. Therefore updated and more privatised based O&M practise should be re-considered and put into practice as soon as possible.
At present, with over 15 years of field experience of other countries, it became clear that in many cases the best working O&M system for rural dispersed handpumps in Africa is not only VLOM, but that alternative O&M systems, especially privatisation of maintenance, is developing more and more.
An example of alternative O&M during project implementation is therefore to focus more on the training of technicians from an existing local organisation (like a water company) and not only to train some persons in the village. Such an organisation can take care (for a commercial price) of the regular maintenance and repair of 20 to 50 handpumps in their area. The spare parts that they need for these repairs, are provided by:
Important in this set-up is, that this organisation or service point has transport facilities (minimal a motto-bike) and some additional logistics as access to a telephone.
This rather new, but successful privatised maintenance concept is in contradiction with the present promoted VLOM - O&M procedures in Africa, were the repairs by the users in the village is promoted and local user groups are trained to do the repairs. In general, experience shows that the VLOM approach can work very well when there is a very high density of simple handpumps that often need repairs (10 to 25 per km2) which is for instance the case in countries like India.
However, in the African rural context the situation is often different, and it should be made clear to the users that the sustainable service of safe water from handpumps requires commercial spare parts supply and commercial repairs, especially critical when the waterlevels are deeper than the standard depth of 40 m.
The producer of the Volanta (Jansen Venneboer International BV in Holland, JVI) has an ongoing Research and Development program to monitor field experience and to improve the O&M of the Volanta. As a result from this program, from time to time modifications to the standard Volanta are introduced and the design is updated according to ISO 9001. Some modifications are not yet standard and still have the character of experimental due to the fact that JVI prefers to first evaluate a relative number of years of fielddata before to officially change the standard design of the Volanta. However, at request these recommended (experimental) modifications are already available.
· long conical seat socket, (to allow for cylinder protection and support, with an additional Boode PVC filter, around the cylinder, see also www.boode.com).
· A bottom support option, consisting of a “platform” of the same PVC pipes, These pipes can also be glued together in a way that they will form a floating support platform for the PVC cylinder filter for additional support and easy installation in very deep boreholes. It is expected that this will considerably increase the lifetime of the rising main, however, more field-testing is required to obtain final results and insight in the effect on long term of this option.
· New position of the handle on the flywheel: 60 degrees to the left (to make pumping more easy, as the pulling movement on the flywheel will coincide with the downward stroke of the rods).
· Adjustable counter weight on the Flywheel, to make pumping easier and smooth, by neutralising the weight of the rods.
· Simplified design of the guiding rings (now two of the same rings and only two pressures rings).
· New socket with a longer sleeve and a “zero-fit” for the PVC tubes (to assure a better connection and to avoid de-gluing in deep boreholes).
For several African countries: an important part of the Volanta (Flywheel and Stand) can be locally made to promote local production with a local turnover of at least 250 US$ per Volanta.
DURING THE INTERNATIONAL Drinking Water Supply and Sanitation Decade of the 1980s many thousands of handpumps were installed in developing countries as part of the United Nations-led drive to provide safe drinking water and adequate sanitation for all by 1990.
Since then, thousands more handpumps of many different types have been put in by donors and governments. Handpumps have been given a high profile in the quest to provide potable water to the world's burgeoning rural population by leading players in development like the World Bank, UNICEF and a plethora of international non-government organizations. Handpumps were vigorously promoted as being the best option by which communities could enjoy a safe and reliable water supply, based on the following set of assumptions:
That handpumps were:
· Low cost
· Easy to maintain
· An appropriate technology
· Readily available
· Easy to install
· User friendly
It has been generally accepted that handpumps render a shallow well or borehole safe against surface contamination based on the belief that the water will be contaminated to an unacceptable degree (having an E-Coli count of more than 10) if alternative extraction methods are used e.g. rope and bucket.
This paper will point out that handpumps have not lived up to earlier expectations, particularly in the area of affordability, and that donors and recipient governments would be well advised to consider other less politically correct options, under certain circumstances.
The first generation of handpumps included such stalwarts as the British made Godwin, which were installed in the 1930s,40s and 50s. They used super heavy duty materials like cast iron and hardened steel in the belief that one had, in the colonial era, to make pumps virtually indestructible so as to withstand constant use and abuse by people in the Third World who could not be expected to maintain, let alone repair, such advanced pieces of technology.
To their credit, many such pumps continued to pump water for many years beyond their original life expectancy, but many also broke down and stayed that way for months or years because government mechanics did not come to repair them for a variety of well-documented reasons.
During the 1960s and 70s a second generation of handpumps emerged, of which the India Mark II is the most notable example. With over five million installed worldwide, this is undoubtably the world's most widely used handpump. At the time of its development in India in the early 1970s, the Mark II was heralded as being the answer to the myriad problems of rural water supply.
However, this pump relied on a three-tier maintenance system. Although such a system was developed in India, in 1986 it was reported (World Water Conference, Nairobi) that over one million India Mark II pumps were broken down on the sub-continent.
The pump was, however, considered an affordable option at least in the Indian context where intense competition in the burgeoning manufacturing sector kept costs down.
It is still probably the most cost-effective handpump for depths up to 45 metres, even in Africa where high freight costs have always made imported pumps more expensive than they are in India.
But in Africa, the Mark II has not been a sustainable solution to rural water supply problems, mainly because the Indian-style tiered maintenance system frequently failed or simply was not there in the first place.
During the 1970s, the World Bank/UNDP pioneered the concept of a simple handpump which could be maintained at the village level in Africa. The Bank financed the development of what became known as the Afridev, based on the belief that handpumps must be made and maintained locally, by local people. The Afridev design featured state-of-the-art light weight, non-corrosive, easy-to-assemble materials developed in co-operation with the Swiss multinational company, Dupont. Ironically, manufacture of the Afridev has never really taken off in Africa. One of the reasons being the extremely high price of the mould needed to produce the nylon bearing-bushes and the footvalve/plunger. Also, high import tariffs on raw materials make the manufacture of Afridevs in African countries expensive.
The Afridev is, however, being made in large numbers at competitive prices in India and Pakistan and is being sold for installation in African countries cheaper than African-made Afridevs !
One of the main reasons is that in most African countries the small scale industrial base is not nearly as developed as is the case in India or Pakistan. The price of a European-made Afridev landed in an African country right now is about US$900.00; about double what an Indian-made Afridev costs!
The donor community throughout the Water Decade, did much to persuade governments of developing countries that handpumps per se offered the best option in making safe water available to burgeoning rural populations.
The advent of the Village Level Operation and Maintenance handpumps in the late 1970s to early 1980s did much to further the handpump option, particularly in Africa with the Afridev leading the way toward the goal of affordable village-based maintenance.
Sustainability may be defined as an intervention which is capable of being supported and maintained by a community or individual over an extended period of time with an absolute minimum of outside assistance.
VLOM handpumps were developed and installed in remote rural areas because it was assumed that the users themselves would be able to maintain them. In many cases in Africa this has proved impractical due to a number of technical problems with the Afridev pump concerning:
· The PVC rising main
· The method of joining pump rods
· The nitrile rubber seal and O ring
· Fishing tools
· The supply of spare parts kits
The Afridev blueprint specifies a 63mm O.D. PVC riser pipe having bell joints glued together. Originally it was thought that it would be unnecessary to remove these pipes once installed in the well. This is a big selling point. However, experience in Malawi, Ghana and Ethiopia has revealed that in some types of Afridev, the rod connector wears a hole in the riser pipes, necessitating their removal by sawing and re-gluing using PVC sockets.
This operation is beyond the means of handpump caretakers. Also, PVC risers installed in wide-diameter wells tend to flex during pumping causing joint fatigue leading to cracking of the PVC pipe. Little thought has been given as to how to secure PVC pipes in the well.
Some manufacturers use a plastic clip-on device for joining the rods. These can and do come off after a few months use, necessitating the use of a fishing tool to extricate the fallen rods. The type of fishing tool supplied by the manufacturer is not able to do this job, so a special tool has to be fabricated. This too is beyond the means of handpump caretakers in the village.
Experience has shown that the nitrile rubber plunger seal and footvalve O ring actually absorb water over time, and expand. This makes their removal difficult, especially in the case of removing the footvalve.
It is recommended by Afridev manufacturers that the plunger seal, bearing bushes and footvalve bobbins and O ring be replaced annually as a preventive maintenance strategy. However, the issue of how the spare-parts kits are going to be supplied to the village caretaker has not been fully addressed. Difficulties arise when donors try to supply spare parts at the village level. Who is to look after them? Is the village expected to pay? Who is going to collect and keep the money? Are parts to be given freely or should a nominal charge be levied ?
Many thousands of handpump caretakers, many of them women, have been trained to maintain handpumps like the Afridev. But this pump still has its problems. Can caretakers and their assistants fully repair this type of handpump? Experience to date suggests that they cannot. Most water supply projects have convenient showpiece communities not far from project headquarters where groups of highly trained women impress visitors by whipping out the rods and changing the plunger seal in textbook fashion.
What is less well known, but just as common, is that VLOM handpumps have failed in remote rural areas because problems have arisen beyond the means of the trained caretakers to repair.
Beautiful wells have been rendered useless and people have been forced back to traditional, unprotected sources because the VLOM handpumps have broken down, typically with rising main problems.
In Africa, the India Mark II does not enjoy an impressive record of sustainability mainly because there are not the village level mechanics available that are commonly found in rural areas of India, where the popularity of the ubiquitous bicycle has encouraged a culture of village bicycle repair shops whose mechanics are ideally suited to repair handpumps, a technology on a par with that of bicycles. As the bicycle makes inroads into the African countryside we can expect an upsurge in the repair business which will augur well for the continued sustainability of handpumps.
When we talk of affordability we must ask, affordable to whom? Who is paying? It has been said, for example, that the Afridev is an affordable handpump for Ethiopia. (Second National Handpumps Workshop, Addis Ababa, UNICEF, Jan.92). But is it?
In 1992 a bilateral aid project in Ethiopia imported 165 Afridevs from India costing US$660 each including airfreight. If the cost of clearing, transport to the site and installation costs are included, the installed cost comes to around $700. Each handpump serves about 55 households. The World Bank states that the average per capita income in Ethiopia is $120.
Therefore, if the users were paying, each family head would have to pay $12.72 or 11 per cent of their annual income. This is more than double the five per cent guideline that the Bank has said is the maximum that families should have to pay for safe water. Clearly, in this scenario handpumps were not an affordable option.
The technical shortcomings mentioned above and the expense involved call into question whether handpumps, such as the Afridev, are the most appropriate and sustainable solution to potable water supply problems in rural areas. In isolated rural communities in the Tigrayan mountains of Ethiopia, or across the savannah lands of the Sahel, where outside technical assistance may be weeks or months in arriving, communities have been left without a safe water supply because their so-called VLOM pump failed and they couldn't fix it.
Having shown that handpumps may not be affordable or technically sustainable, we have to ask, What is the alternative?
One answer is Back to Basics!
Back, in fact, to the age-old rope and bucket system. But that is not the whole solution if contamination is to be kept to a minimum.
Coupled with this simple approach, must come improved well-head design featuring a large, well-drained concrete apron, a protective parapet and a simple windlass to which the rope is attached. Having a dedicated bucket, be it half an inner tube or a proper bucket, will further reduce the risk of contamination.
An integral part of a rope and bucket system must also incorporate a hard-hitting hygiene education program which focusses on women, the main users and managers of household water, and children, who are the most receptive to behavioural change.
Hygiene messages should be simple, to the point and unambiguous. The user community must be targeted with a well-thought out, ongoing education program, NOT just a blitz-like campaign that is here today gone tomorrow.
VLOM handpumps cost from $US400 to 800 each. The money saved by NOT installing a handpump could be used:
· To finance improved well-head works
· To conduct ongoing and effective hygiene education programs
· To build more wells in other communities thus making potentially safe water more available to more people.
Some people will undoubtably think that the rope and bucket system is taking a step backwards; that it is too primitive; that rural communities deserve something better.
In some cases handpumps are indeed viable and sustainable, even affordable. But in many isolated rural communities in the emerging countries of the South, many millions of people still live and die of preventable diseases associated with unsafe water supply and inadequate sanitation facilities.
In order to increase coverage; to scale up to the levels required, we should not put all our faith in handpumps, but rather concentrate on more sustainable and more affordable solutions to the problems of rural water supply, so as to transform the goal of Health for All by the year 2000 into an achievable reality.