Human and animal powered water lifting devices
Practical Action
Advantages
Disadvantages
A relatively inexpensive traditional technology
which can be locally made and maintained.
Easy to operate
Limited to lifts of less than 4 m
Limited water yield, 60 l/min suitable for small
fields
Relatively efficient (30-60%)
Dhone
The dhone consists of a trough
made from a wooden log or iron
sheet; closed at one end and open
at the other. The trough is
mounted on a suspended pivoted
lever to produce a see-sawing
gutter or dhone which operates at
relatively low lifts of up to 1.5 m.
The trough is lowered into the
water by exerting pressure using a
rope or the foot of the operator
until the closed end is submerged
in water. Upon releasing pressure
the trough comes to its original
position and the water is delivered
to the irrigation channel. Typical
yields of 80-160 l/min can be
obtained from the dhone between 0.3-1.0 m.
Figure 4: Dhone
Source: Water Pumping Devices
Advantages
Disadvantages
A relatively inexpensive traditional technology
which can be locally made and maintained.
Easy to operate
Limited to lifts of less than 1.5 m
Low to medium efficiency (20-50%)
Water yields of approximately 160 l/min for
lifts of less than 1 m
Paddle wheel (Chakram)
The paddle wheel is only suitable for low water lifts
of up to 0.5 metres and it is mostly used in coastal
regions to irrigate paddy fields.
Small paddles are mounted on a horizontal shaft,
which rotates in a close fitting concave trough,
pushing water upwards. The operator walks directly
on the rim of the paddle wheel, turning it so that it
continuously and steadily scoops up water and
deposits it into the irrigation channel.
The paddle wheel is not particularly efficient
because a lot of water lifted flows back around the
edges of the blades and hence it is not used
extensively. However it is simple to build and install
in situations where a lot of water needs to be lifted
through a small height. A paddle wheel with 12
blades can lift 300 litres/ min at depths of 0.5
metres.
4
Figure 5: Paddle Wheel
Source: Water Pumping Devices