TRADITIONAL METHODS OF WATER CONVEYANCE WATER LIFTING DEVICES
HIMA KARTHIK. S 1190100870 II YEAR IV SEM SPA VIJAYAWADA
The scoop used as a simple hand tool
Scoop with a rope support
Swinging basket
Scoops, bailers and the swing-basket represent methods of speeding up the process of filling, lifting and emptying a bucket; the latter also uses two people rather than one and thereby increases the mass of water that can be scooped in each swing.
SWINGING BASKET In this method water is lifted by means of a basket from the low channels or ponds which are by the side of the field. The basket is made of any cheap material for example leather, tin etc. The basket is slung by ropes on both sides. . Two persons hold the ropes at ends and dip the basket in the channel water. Then swing is given to the basket so that the basket full of water tilts over the water course and discharges water in the water course. This method is useful up to a height of 75 cm. If the lift is more the same method may be used in stages. In such cases in between the water course and the source of water temporary ponds may be constructed. The water from the source is transferred to the pond just above and from there onwards till water reaches the field channel. Such a case will be of course very costly, but in hilly tracts one has to adopt this method.
SHADOUF (PICOTTAH) The basic shadouf consists of a rope, pole, bucket and counterweight and is capable of lifting water up to 4 metres. The counterweight can be just a heavy rock, but in the more advanced picottah design, one person guides the bucket while the other acts as a moving counterweight. It is generally used for lifting water fromunlined wells, streams or ponds for irrigating small fields. Approximately 60 litres/ min can be lifted from a depth of 2 to 3 metres.
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.
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.
MOTE/ CHARSA/ PUR The simplest and cheapest method of lifting groundwater remains a rope and bucket in a wide, shallow well. This type of well can operate up to a depth of 100 metres, although they rarely exceed 45 metres. The system consists of a leather container whose shape is like a funnel. There is a spout on one side and shape of upper portion is that of a conical cylinder. It is open at both ends.Two ropes are tied to two ends of the mote as shown. The ropes pass over two pulleys. A pair of bullocks is employed to haul the mote. The bullocks move forward and backward on a sloping bullock run or a ramp. The discharging water may be collected temporarily in a trough constructed in front of the cylindrical pulley from where water is taken to the water course.
THE PERSIAN WHEEL It is also known as Rabat in some parts of India. This arrangement is very suitable where the depth of well is from 12 to 20 metres. Once this method was very commonly used in Uttar Pradesh and Punjab. This method is very suitable for irrigating crops when the wells and persian wheels are in abundance and area supported by each is less. It is also very much sutiable for gardening. It consists of an endless chain of buckets made of G.I. Sheets. The chain is mounted on a drum. The endless chain is suspended in the well in such a way that the chain dips in the water to sufficient extent. The drum is connected by means of a horizontal axle to a toothed wheel which is also held in a vertical plane. This vertical wheel is geared with a horizontal wheel.The vertical axle of the horizontal wheel is connected to a horizontal shaft.
A pair of bullocks or buffaloes or a camel is yoked to the shaft by means of ropes and a yoke. The horizontal shaft is rotated with the help of animal power about the vertical axle. When the animal moves round the vertical axle of the system rotates. As a result bucket chain also moves. The buckets filled with water move up and when they turn down at the top of the drum the water is discharged. This water is collected in a trough from where it goes to the water course. The empty buckets then move onwards and go down in the well finally dip in the water of the well in inverted position and when they emerge out they are upright and completely filled with water. Thus the buckets when ascend are full of water and when descend they are empty. In this method water is lifted continuously as long as system is kept in rotation. This Method is very efficient.
NOIRA The water-powered noria uses the same principle as the Persian wheel and therefore also needs to be of larger diameter than the pumping head, which either limits it to very low lift pumping or requires very large, cumbersome and expensive construction.
IMPROVED PERSIAN WHEEL
Zawaffa type of Persian wheel
The traditional wooden Persian wheels also inevitably need to be quite large in diameter to accommodate a large enough collection trough to catch most of the water spilling from the pots; this in turn requires a large well diameter which increases the cost. Metal Persian wheels can be made smaller in diameter, which reduces the extra height the water needs to be lifted before it is tipped out of the containers, and also reduces the well diameter that is necessary.
Sakia or Tympanum
It consists of a large hollow wheel with scoops around its periphery, which discharges water at or near its hub rather than from its top. The diameters for sakias range from about 2-5m. Sakias are now normally made from galvanized sheet steel. The normal operating speed is 2-4 rpm for animal-driven sakias, and 8-15 rpm for motorised or enginepowered units.
CONCLUSION The Persian Wheel is perhaps actually the Indian Wheel. Extensive irrigation must have become possible through the use of animal power and this technological development would have helped extend irrigation to larger tracts of land. But falling water tables have made the Persian wheel redundant as well as the arrival of the electric pumps, their greater yield and cost efficiencies. However, the Persian wheel represents a water culture and water heritage of India.
SOURCES • http://www.fao.org/3/ah810e/AH810E05.htm • https://akvopedia.org/wiki/Bucket_elevators,_Persian_wheels_and_Norias#:~:text=I mproved%20Persian%20wheel%2C%20(Zawaffa%20or%20Jhallar)&text=Traditional% 20wooden%20Persian%20wheels%20were,%2C%20India%2C%20Pakistan%20and%2 0Egypt . • https://www.yourarticlelibrary.com/water/wells/methods-of-lifting-water-using-man power-6-methods/61062 • https://www.indiawaterportal.org/articles/persian-wheel-water-lifting-device-kolar-k arnataka • https://rainwaterharvesting.wordpress.com/2008/02/23/the-persian-wheel-revisitedaraghatta/ • Human and animal powered water lifting devices_Practical Action_A tractical brief produced by Jane Olley for Practical Action, November 2008.