BRIEF DESCRIPTION OF TECHNOLOGY

Handpumps are water-lifting devices installed on boreholes and wells. They have a piston placed in a cylinder below the water level, which is usually in the range of 15 to 45m below the ground. It is however possible to lift water from a depth of up to 100m. The pumping motion by the user at the pump stand is transferred to the piston by means of a series of connected pumping rods inside the rising main. When the user lifts up the handle (up-stroke) the plunger lifts water into the rising main and replacement water is drawn into the cylinder through the foot valve. On the down stroke the foot valve closes and water passes the plunger to be lifted up on the next up-stroke. The pumping height is limited only by the effort needed to lift water to the surface. Pumps in this category can deliver 0.25-0.36 l/s at 25 m and 0.18-0.28 l/s at 45 m depth.

It is becoming common these days to have cylinders with an open top to allow the piston and foot valve to be removed without removing the rising main and cylinder. The connecting rods are specially designed to allow for assembly and dismantling using simple tools. The connecting rod joints incorporate centralisers to prevent wear of the riser pipes.

The common types of handpumps are: India Mark II, India Mark III, Afridev/Aquadev, Pestobell Micro, Bush Pump and Blair.

1.  DESCRIPTION OF O&M ACTIVITIES

Operation

Operation of the handpump involves moving the handle up and down with a hand. In other models a flywheel is rotated with a hand. Handle forces should be kept within acceptable limits to avoid damage depending on the brand and lifting height. The pump must be kept clean.

Maintenance

Maintenance activities for handpumps involve regular preventive maintenance measures, minor repairs and the more specialized major repairs. Preventive maintenance will include checking the functioning of the pump, cleaning of the pump site, greasing, checking of pump parts, dismantling of the pump for thorough check, cleaning of the pump parts with water and painting pump stand. Corroded connecting rods should be replaced. Normally GI rods are replaced every five years. Riser pipes with corroded threads should also be replaced.

Minor repairs involve replacement of bearings, cupseals and washers, replacing/straightening bent connecting rods. Major repairs normally involve replacing the plunger, foot valve, cylinder, riser pipes, fulcrum, pump handle and connecting rods. These major repairs and problems may require external support. Pumps with closed cylinders require special lifting equipment and tools to dismantle and assemble them.

3. OPERATION AND MAINTENANCE REQUIREMENTS

Activity / Frequency / Human resource / Materials & spare parts / Tools & equipment
Clean pump and site / Daily / Local / Broom, brush
Grease bearings / Weekly / Local / Grease or oil / Lubricantor
Check pump stand parts / Monthly / Local / Spanner
Replace pump stand parts / Occasionally / Local / Nuts and bolts, bearings, pump handle / Spanners, screwdriver
Replace cupseals / Annually or less / Local or zone / Cupseals / Spanners, screwdriver, wrench, knife etc.
Redo threads in pump rod or main / Occasionally / Local or zone / Oil / Pipe threader, tackle
Replace foot valve, plunger or cylinder / Occasionally / Zone / Foot valve, plunger or cylinder / Spanners, wrench
Replace pump rod or main / Occasionally / Zone / Pump rods or main tubing / Spanners, wrench, pipe threader
Repair platform / Annually/occasionally / Local / Gravel, sand, cement / Bucket, trowel

4. ACTORS INVOLVED AND SKILLS REQUIRED IN O&M

ACTOR / ROLES/RESPONSIBILITIES / SKILLS
User / Pump water, keep site clean, report malfunctioning, raise O&M funds / No special skills
Caretaker / keep site clean, regularly check pump, carry out small repairs, enforce operational and hygiene rules / Basic skills in O&M
V-WASHE / Supervise caretaker, collect fees / Organizational skills
Sub District WASHE / Monitor and facilitate O&M activities, training Caretakers in hardware and software components and conduct participatory education to V-WASHEs stimulate and guide community organization / Organizational skills
Area mechanic (private sector) / Perform major repairs / Special technical skills
D-WASHE / Check water quality, provide backup support services to Area Mechanic and SUB-DISTRICT WASHE / Water quality analysis and organizational analysis skills

Organisational Aspects

Implementation of O&M activities requires well-defined structures, roles and responsibilities, a clear mechanism for decision-making and an effective support system.

In Northern Province the primary actors in O&M activities are communities. They should establish a system to effectively deal with issues of control, use and finances. Pumps require adequate O&M attention as they have a number of individual components and parts that need maintenance. A mere loose nut may result into pump malfunctioning. Incidents of pumps not working for years because of a disconnected rod are quiet common in Northern Province and elsewhere. A properly organized and managed system will assist reduce social conflicts over O&M issues.

5. CAPITAL AND O&M COSTS

Capital cost for a pump range from 400 to 700 US dollars (Zk 2,000,000 to Zk 3,500,000 – December 2004 rate).

O&M costs include maintenance and repair costs for activities described under O&M requirements. For the common handpump used in Northern Province (India Mark II), O&M costs would normally range from 50 to 60 US dollars (Zk 250,000 to Zk300, 000 - December 2004 rate) annually.

6. LIMITATIONS, PROBLEMS AND REMARKS

Limitations

Common limitations to handpumps are:

·  Maximum lift is limited to 45 to 100m depending on the brand of pump.

·  The energy or force required to turn the handle may be too high in some cases, especially for deep boreholes.

Problems

Common problems with handpumps are:

·  Frequent wear of the cupseals.

·  Wrong installation and poor quality control.

·  Connecting rods getting disconnected.

·  Corrosion of both the connecting rods and riser pipes.

·  Shaky or broken handles mainly due to worn out bearings.

NB: The frequency of the problems increase with increased depth of the borehole.

Remarks

A properly installed and maintained handpump can last up to 12 years. Handpumps are more favourable where ground water table are within 100m but preferably 45m from the surface. Quality control in the production and in the installation of pipes, rods and all the other components of the handpump is required in order to minimize on the number of breakdowns. It is important that a Caretaker is appointed and trained in basic maintenance activities to ensure that the handpump is sustained. Similarly the Area Mechanic is another key player in the organization for sustenance of the handpump.

7.  FURTHER REFERENCE

§  International Research Centre (IRC), Linking Technology Choice with Operation and Maintenance for Low Cost Water Supply and Sanitation, 1997. The Hague, Netherlands.

§  P-WASHE Northern Province, Manual on Boreholes, 2004. Kasama, Zambia. (Unpublished)

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