This is the VOA Special English Agriculture Report.
In many places, farms require asystem to move water to fields where it is needed. For many smallfarms, a treadle [TRE-dul] pump may be the answer. A treadle pumpuses leg power to force water up from the ground. Treadle is spelledT-R-E-A-D-L-E. Here is how it works.
A treadle pump is designed kind of like the engine in a car.Pistons move up and down inside cylinders to create suction force.With a treadle, this force pulls water from one place and moves itto another.
There are many different designs for a treadle pump. But all havetwo cylinders. These can be made from lengths of pipe. The surfaceof the sliding piece inside can be made of rubber or leather. Astick is attached to move the piece up and down. The piston must fitclosely inside the pipe, but must also be able to move along itslength.
Two openings are cut into the bottom of each pipe. These openingscontrol the force of each piston. Valves are placed in the openings.Valves are like doors that open only one way. When the piston goesup, one valve opens. The force of suction takes water into the pipe.When the piston moves down, it forces the water out of the pipe. Thesame force opens the other valve and carries water to where it isneeded.
The easiest design is to use two long pieces of wood to stand onto operate the pistons. The operator stands above the pump andpushes down on one piston with one foot while the other pistonrises. This movement is much like walking.
Treadle pumps can be made with common parts. Companies in manycountries also sell them for prices between ten and twenty-fiveAmerican dollars.
These human-powered pumps can lift water several meters. They canpump water from underground supplies or lift water from rivers tohigher ground. But treadle pumps do have limits. They cannot liftwater from deep underground supplies. Also, treadle pumps lose aboutten percent of their power for every kilometer above sea level. Sothey are not effective in high mountain areas.
Still, for many small farms, treadle pumps can increaseproduction with less effort. The Food and Agriculture Organizationof the United Nations says treadle pumps can help farmers improvecrops and increase profits.
This VOA Special English Agriculture Report was written by MarioRitter.