Frequently Asked Questions
Version 20-11-2013
Who invented the Rope pump?
The ancient principle of the Rope pump was used 1000 years ago in the Middle East and known as the Noria Pump. In the 70s this effective pumping system was “rediscovered” by Mr R. van Tijen of the Dutch Demotech organisation, who started to use PVC pipes for pumping and used car tires for the wheel. As Rope and washer pump it was introduced in Africa among others by ITDG, as a low lift pump for irrigation and family wells. It never really took off probably for reasons as its low lift and “Stone Age” image and the lack of involvement of the local private sector. This changed in Nicaragua where the Rope pump was introduced in 1986. The Dutch organisation SNV and others made technical improvements and first dissemination and the company Bombas de mecate SA made it a commercial success via sales to the private sector and later on to NGOs and Government. Now the Rope pump provides some 40% of the rural water supply in Nicaragua (Ref. 1) and is produced by some 10 workshops. Since 2000 this technology started to spread out again to Africa and Asia. Rope pump producers worldwide make “improvements” and feel themselves the inventor! This is exactly the strong (and sometimes weak) point of this innovative and Affordable Technology.
How many Rope pumps are in use and where?
An estimated 110.000 used by 4 million people. Numbers may be higher since not all Rope pump producers and NGOs report their production. Most Rope pumps are used in Nicaragua (70.000) and neighboring countries (20.000) but the Rope pump is now also used in Cambodia (4000) and India. In Africa it is used in Zimbabwe and Malawi as The Elephant Pump (8000), Ghana, Victoria pump (2000) in Ethiopia, Practica model (10.000) in Zambia and Tanzania, SHIPO model (5000), in Malawi (Pole model for irrigation), Mozambique, Madagascar (Ref. 2)
Is the Rope pump fit for communal water supply?
There are different opinions on this since the Rope pump is a semi open pump and requires frequent maintenance. In Nicaragua. Tanzania and other countries Rope pumps are used in communities and schools. In general it is best to not have more than 150 users to avoid to frequent repairs. In Nicaragua the Rope pump is a national standard for hand pumps used for both communal and family wells by organizations as UNICEF, CARE etc. However to start in a new area or country it is advised to start with the Rope pump as a Family pump or as a pump for productive use (irrigation). If it works well, expand to small community pumps in cooperation with local or national governments. In all cases it is strongly recommended to use updated manuals combined with training by professional organizations and focus on quality.
For how many people can one Rope pump supply water?
The recommended maximum number of people for one Rope pump is 150 (30 families),but there are examples that well produced and installed Rope pumps are used by 400 people for 10 years or more. In all cases training of the users in maintenance (oiling the bushings etc.) and training of the local producers in repairs, of pump pipes, rope etc. is essential.
Why are some Governments and NGOs reluctant to use the Rope pump?
Some mayor reasons seem;
The Rope pump is simple so why is it difficult to reproduce?
Experiences with this and other technology is; SIMPLE is NOT EASY. Even a simple technology as a Rope pump requires quality in production, installation and maintenance. Evaluations of IRC and others indicate that, if this is done right, over 90% of the Rope pumps stay working even after many years of installation. In general it can be said that if Rope pumps do not work well, it is not because of the design but because of errors in construction, installation and / or lack of user involvement for ownership / maintenance. There are many examples (Ghana, Mozambique, Ethiopia, etc.) where the first introduction of the Rope pump was a failure. There were breakdowns more often than needed and this has given a bad image to the Rope pump. It requires many good examples to repair a bad image.
Another reason maybe that policymakers do not like to take risks so rather use known technologies as Afridev, Indian Mark 2, etc. Also with Rope pumps there are less possibilities for “commission” since they are not imported but produced decentralised by local workshops. Despite all this NGOs like UNICEF, Water Aid, Care, World Vision and others are using Rope pumps in their programmes.
Is the water from a Rope pump safe to drink?
A pump does not change quality of the water but just pumps it up. If water in the well is contaminated the water from the pump is contaminated also. Investigations in Tanzania (ref 3) and other countries indicate that, if installed well, water from Rope pumps has more or less the same quality as pistons pumps. (ACCRA study Tanzania 2012) In general water from protected wells and deeper water layers is safe to drink. In case of doubt it is recommended to treat the water at the Point Of Use, with disinfection options or household filters. Besides boiling and chlorine there are new low cost treatment options like Agua prove, Aguatabs, Pot filters, Table top filters and Siphon Filters.
What are advantages of Rope pumps compared to Piston pumps?
What are disadvantages of Rope pumps compared to Piston pumps?
Semi open pump so the water in the well can be contaminated by touching the rope by hands. Some evaluations on this aspect indicate some difference in water from Piston pumps and Rope pumps. Others indicate no difference (of course on condition that well cover, apron and seal are OK.) The Rope pump cannot pump higher than the height of the wheel. If water outlet needs to be higher, an additional wheel is needed on a post.
Can the rope pump be installed on small boreholes?
Rope pump can be installed on boreholes as small as 2” (56 mm inside). In this case a ½” pump pipe is needed and a small guide box. Most Rope pumps are installed on casings of 3 to 4 inch and even more on hand dug wells with diameters of 0.8 to 3 meters
What is the cost of a Rope pump?
Prices vary from 30 to 200 US$ and depend on model, cost of materials, cost of labour and production efficiency. In projects the cost of a Rope pump often is higher since it includes cost of installation, training of users, time to form water committees, monitoring etc. The prices mentioned do not include cost of the well.
What are the maintenance cost per year?
Cost varies from 5 to 30 US$/year. Cost consist mainly of oiling bushings every week and replacing the rope and pistons. The frequency of rope replacements depends on use and rope quality. Bushings can last up to 20 years as proven in Nicaragua. Ropes last 6 months to 6 years. Pistons in general last 2 times longer than the rope. Pump pipes or guide boxes are hardly wearing. The PVC parts exposed to the sun should be of thick quality and protected by paint.
What is the pump capacity / minute of a Rope Pump?
Who invented the Rope pump?
The ancient principle of the Rope pump was used 1000 years ago in the Middle East and known as the Noria Pump. In the 70s this effective pumping system was “rediscovered” by Mr R. van Tijen of the Dutch Demotech organisation, who started to use PVC pipes for pumping and used car tires for the wheel. As Rope and washer pump it was introduced in Africa among others by ITDG, as a low lift pump for irrigation and family wells. It never really took off probably for reasons as its low lift and “Stone Age” image and the lack of involvement of the local private sector. This changed in Nicaragua where the Rope pump was introduced in 1986. The Dutch organisation SNV and others made technical improvements and first dissemination and the company Bombas de mecate SA made it a commercial success via sales to the private sector and later on to NGOs and Government. Now the Rope pump provides some 40% of the rural water supply in Nicaragua (Ref. 1) and is produced by some 10 workshops. Since 2000 this technology started to spread out again to Africa and Asia. Rope pump producers worldwide make “improvements” and feel themselves the inventor! This is exactly the strong (and sometimes weak) point of this innovative and Affordable Technology.
How many Rope pumps are in use and where?
An estimated 110.000 used by 4 million people. Numbers may be higher since not all Rope pump producers and NGOs report their production. Most Rope pumps are used in Nicaragua (70.000) and neighboring countries (20.000) but the Rope pump is now also used in Cambodia (4000) and India. In Africa it is used in Zimbabwe and Malawi as The Elephant Pump (8000), Ghana, Victoria pump (2000) in Ethiopia, Practica model (10.000) in Zambia and Tanzania, SHIPO model (5000), in Malawi (Pole model for irrigation), Mozambique, Madagascar (Ref. 2)
Is the Rope pump fit for communal water supply?
There are different opinions on this since the Rope pump is a semi open pump and requires frequent maintenance. In Nicaragua. Tanzania and other countries Rope pumps are used in communities and schools. In general it is best to not have more than 150 users to avoid to frequent repairs. In Nicaragua the Rope pump is a national standard for hand pumps used for both communal and family wells by organizations as UNICEF, CARE etc. However to start in a new area or country it is advised to start with the Rope pump as a Family pump or as a pump for productive use (irrigation). If it works well, expand to small community pumps in cooperation with local or national governments. In all cases it is strongly recommended to use updated manuals combined with training by professional organizations and focus on quality.
For how many people can one Rope pump supply water?
The recommended maximum number of people for one Rope pump is 150 (30 families),but there are examples that well produced and installed Rope pumps are used by 400 people for 10 years or more. In all cases training of the users in maintenance (oiling the bushings etc.) and training of the local producers in repairs, of pump pipes, rope etc. is essential.
Why are some Governments and NGOs reluctant to use the Rope pump?
Some mayor reasons seem;
- It is a semi open pump so perception is that the rope can contaminate the water in the well.
- Wrong examples because of lack of follow up, lack of ownership and technical errors in construction and installation so many unnecessary breakdowns.
- Lack of awareness at implementing level on both technical and social improvements.
The Rope pump is simple so why is it difficult to reproduce?
Experiences with this and other technology is; SIMPLE is NOT EASY. Even a simple technology as a Rope pump requires quality in production, installation and maintenance. Evaluations of IRC and others indicate that, if this is done right, over 90% of the Rope pumps stay working even after many years of installation. In general it can be said that if Rope pumps do not work well, it is not because of the design but because of errors in construction, installation and / or lack of user involvement for ownership / maintenance. There are many examples (Ghana, Mozambique, Ethiopia, etc.) where the first introduction of the Rope pump was a failure. There were breakdowns more often than needed and this has given a bad image to the Rope pump. It requires many good examples to repair a bad image.
Another reason maybe that policymakers do not like to take risks so rather use known technologies as Afridev, Indian Mark 2, etc. Also with Rope pumps there are less possibilities for “commission” since they are not imported but produced decentralised by local workshops. Despite all this NGOs like UNICEF, Water Aid, Care, World Vision and others are using Rope pumps in their programmes.
Is the water from a Rope pump safe to drink?
A pump does not change quality of the water but just pumps it up. If water in the well is contaminated the water from the pump is contaminated also. Investigations in Tanzania (ref 3) and other countries indicate that, if installed well, water from Rope pumps has more or less the same quality as pistons pumps. (ACCRA study Tanzania 2012) In general water from protected wells and deeper water layers is safe to drink. In case of doubt it is recommended to treat the water at the Point Of Use, with disinfection options or household filters. Besides boiling and chlorine there are new low cost treatment options like Agua prove, Aguatabs, Pot filters, Table top filters and Siphon Filters.
What are advantages of Rope pumps compared to Piston pumps?
- REPARABILITY There is no “black box” so people understand how it works. The Rope pump is not better than a Piston pump but much simpler to produce and much cheaper to repair. So after training, users can do the weekly maintenance. Spares like pistons and rope can be obtained from the local producer and/or shop. The local blacksmith can do repairs such as welding the handle or pump structure.
- OWNERSHIP In general Rope pump users are proud they can manage their pump so users have ownership, especially if it is used for Self-supply.
- EMPLOYMENT In all countries the Rope pump can be adapted to the materials available in the local hardware store and after training be produced by metal workshops. Local production creates employment and business development.
- LOW COST At same depths Rope pumps are 5 to 10 times cheaper than Piston pumps especially for wells between 6 and 35 m deep (Till 6 meter low cost suctions pumps can also be used). Because of the low cost, Rope pumps are more affordable at family level than Piston pumps and is an option for irrigation. Other low cost family pumps are EMAS Pumps and BAPTIST pumps. See www.AKVO.org
- INCOME GENERATING Because of the low cost and high pump volume, the Rope pump is popular for productive use as irrigation, fish production, car washing etc. Investigations indicate that a family with a dug well and a Rope pump earns 220 US$ more than families with a dug well with a rope and bucket. (Ref. 4) Micro credits for Rope pumps can be paid within 1 year in general.
What are disadvantages of Rope pumps compared to Piston pumps?
Semi open pump so the water in the well can be contaminated by touching the rope by hands. Some evaluations on this aspect indicate some difference in water from Piston pumps and Rope pumps. Others indicate no difference (of course on condition that well cover, apron and seal are OK.) The Rope pump cannot pump higher than the height of the wheel. If water outlet needs to be higher, an additional wheel is needed on a post.
Can the rope pump be installed on small boreholes?
Rope pump can be installed on boreholes as small as 2” (56 mm inside). In this case a ½” pump pipe is needed and a small guide box. Most Rope pumps are installed on casings of 3 to 4 inch and even more on hand dug wells with diameters of 0.8 to 3 meters
What is the cost of a Rope pump?
Prices vary from 30 to 200 US$ and depend on model, cost of materials, cost of labour and production efficiency. In projects the cost of a Rope pump often is higher since it includes cost of installation, training of users, time to form water committees, monitoring etc. The prices mentioned do not include cost of the well.
What are the maintenance cost per year?
Cost varies from 5 to 30 US$/year. Cost consist mainly of oiling bushings every week and replacing the rope and pistons. The frequency of rope replacements depends on use and rope quality. Bushings can last up to 20 years as proven in Nicaragua. Ropes last 6 months to 6 years. Pistons in general last 2 times longer than the rope. Pump pipes or guide boxes are hardly wearing. The PVC parts exposed to the sun should be of thick quality and protected by paint.
What is the pump capacity / minute of a Rope Pump?
Pump capacity depends mainly on depths of the well and is based on the input of 50 to 70 Watt, (50 Watts is the energy of women and children.) The deeper the well, the smaller the diameter of the pump pipe. Capacities are averages and based on 100 RPM and clearance between pistons and pump pipe of 0.5 to 0.8 mm.
What is the maximum pumping depth of a Rope pump?
What is the best Rope pump model?
There is no one best model. There are over 30 Rope pump models since in every country models are adapted to the local situation and local taste. There are Rope pumps of wood that have worked for 15 years, Pumps with wheels of 22 Inch and 12 inch, pumps completely covered with a brick construction or sheet steel. Every Rope pump producer invents improvements and that is the strong point of the Rope pump. In Tanzania, Vietnam and Cambodia there now are family models with production cost of some 35 US$ completely made of GI pipes. All models work if 10 basic design rules are respected.
What are basic design rules of the Rope pump?
Can a Rope pump be powered by an engine?
There are many ways to power a Rope pump including Pedals, Animal, Wind, Gasoline or diesel engine or Electric motor.
Are Plastic (PE) pistons better than Rubber pistons?
Piston can be made out of many different materials and most common are rubber from car tires and HDPE (High Density Poly Ethylene). Rubber pistons can be made with a simple punch or even scissors. The advantage of rubber pistons is that car tires are available everywhere. The piston size can easily be adapted to the often varying inside diameters of the local PVC pipes. Rubber pistons have less friction in water with sand particles, and is very useful to clean and develop a recently drilled borehole. PE pistons can be made with a mechanical press or a small manual operated injection press. The advantage of PE pistons is that is has a standardized size and a more hi tech image so attractive for commercial workshops because other workshops cannot so easy copy it.
When to use a cement guide box and when a steel guide box?
In general cement guide boxes are bigger in size and used in hand dug wells. Especially if wells are deeper than 10 meter the guide box functions to keep the pump pipe straight. In boreholes smaller than 4 inch the guide box has to be small so a metal version is suitable. Guide boxes completely of PVC are being tested in Tanzania and Cambodia.
What are most frequent problems in Rope pumps?
How much area can a Rope pump irrigate?
Can I use a Rope pump for drip irrigation?
Yes, depending on type of laterals.
In general laterals with pre-punched holes (for instance from KB drip) give best results and are most cost effective. This system can be directly coupled to the outlet of the pump. No elevated storage tank is needed.
In Vietnam there are experiments with a “Paddy pump” for rice irrigation.
References
What is the maximum pumping depth of a Rope pump?
- 35 meters with one handle
- 60 meters with two handles (2 persons)
- 100 meters with engine or electric driven models (Strong rope and different piston mountings needed.
What is the best Rope pump model?
There is no one best model. There are over 30 Rope pump models since in every country models are adapted to the local situation and local taste. There are Rope pumps of wood that have worked for 15 years, Pumps with wheels of 22 Inch and 12 inch, pumps completely covered with a brick construction or sheet steel. Every Rope pump producer invents improvements and that is the strong point of the Rope pump. In Tanzania, Vietnam and Cambodia there now are family models with production cost of some 35 US$ completely made of GI pipes. All models work if 10 basic design rules are respected.
What are basic design rules of the Rope pump?
- Wheel should have a good V shape
- The eccentricity of the handle should be the wheel radius plus 1 inch
- Length of the bushings > 60mm and clearance 0.5 -0.8 mm.
- Diameter of pump pipe, see above
- The length of the outlet pipe on top should be 20 cm or more
- Clearance of pistons in the pump pipe 0.5 to 0.8 mm
- Distance between pistons 1 meter
- The rope should be just loose; never tight!
- Handle at height of the belly button. If higher, a platform is needed
- If corrosion is a problem use of galvanized pipes and material.
Can a Rope pump be powered by an engine?
There are many ways to power a Rope pump including Pedals, Animal, Wind, Gasoline or diesel engine or Electric motor.
Are Plastic (PE) pistons better than Rubber pistons?
Piston can be made out of many different materials and most common are rubber from car tires and HDPE (High Density Poly Ethylene). Rubber pistons can be made with a simple punch or even scissors. The advantage of rubber pistons is that car tires are available everywhere. The piston size can easily be adapted to the often varying inside diameters of the local PVC pipes. Rubber pistons have less friction in water with sand particles, and is very useful to clean and develop a recently drilled borehole. PE pistons can be made with a mechanical press or a small manual operated injection press. The advantage of PE pistons is that is has a standardized size and a more hi tech image so attractive for commercial workshops because other workshops cannot so easy copy it.
When to use a cement guide box and when a steel guide box?
In general cement guide boxes are bigger in size and used in hand dug wells. Especially if wells are deeper than 10 meter the guide box functions to keep the pump pipe straight. In boreholes smaller than 4 inch the guide box has to be small so a metal version is suitable. Guide boxes completely of PVC are being tested in Tanzania and Cambodia.
What are most frequent problems in Rope pumps?
- Wearing of the bushings because of misalignment. Clearance to big, lack of oiling or use of grease (new oil is needed, not grease). Bushings should be clean, not black. If well produced and oiled, metal bushings last for 15 years or more.
- Breaking of the rope, often because of wrong alignment or errors in the guide block
- Breaking of handle or other part. Main reason is construction errors in welding.
- Rope gets stuck or rope starts slipping on the wheel. See Manual
- Pump handle is high so loss of energy with pumping. Pump handle should be on the height of the belly button of the average person pumping. If it is higher, then a platform is needed! Information see manuals on www.connectinternational.nl
How much area can a Rope pump irrigate?
- 100 to 1000 m2 depending on crop, depth of well, and hours of pumping
- In Zambia a farmer family irrigate 500 m2 of tomatoes from a borehole of 12 m deep
- In Zimbabwe 1 Rope pump of 10 meter deep is operated by 8 women, irrigating 1000 m2 producing food for 100 people and providing 10 families of water for domestic use.
Can I use a Rope pump for drip irrigation?
Yes, depending on type of laterals.
In general laterals with pre-punched holes (for instance from KB drip) give best results and are most cost effective. This system can be directly coupled to the outlet of the pump. No elevated storage tank is needed.
In Vietnam there are experiments with a “Paddy pump” for rice irrigation.
References
- Transferring the Rope pump to Africa; A long and Winding road? S. Sutton J. Gomme Water lines. April 2009 Vol 28
- A comparative study between “rope pumps” and conventional piston-pumps on water quality. B. Coloru. ACCRA Tanzania Nov.2012.
- A multi sectoral approach to sustainable rural water supply in Nicaragua: the role of the rope handpump. J.H.Alberts (1) and J.J. van der Zee (2)
- Climbing the water ladder: multiple-use water services for poverty reduction. IRC August 2009. For the Water week Stockholm
- Smart Water Solutions, www.nwp.nl
- Myths of the Rural Water Supply Sector. RWSN K Danert Perspectives no 4 2009
- The case for the rope-pump in Africa: A comparative performance analysis P. A. Harvey and T. Drouin. IWA 2006