Question: How does the Tara work? and how is it different to other pumps?

Ken Gibbs answered on 20 Mar 2012:

The Tara works like the vast majority of simple handpumps using two non-return valves (which behave with water just like diodes work in electronic circuits). The difference between the Tara and virtually all other handpumps is that the Tara uses a buoyant pumprod (which means that the rod joining the Tee-bar at the top to the piston down below) is hollow and completely sealed. It tries to float which makes the Tara quite light to pump. Even quite young children can pump it effectively. Besides, the hollow pumprod is made of uPVC which is bendable and can easily be taken out of the borehole by two women. This is VERY important because in many – if not most – countries, women are the only water collectors. When the pump has a problem needing repair, only women are likely to be at the pump.

So, even though the Tara uses principles which ancient Greeks and the Romans used, it is how those principles are applied and the use of modern materials that have allowed it to be so successful.