|Wells Construction: Hand Dug and Hand Drilled (Peace Corps, 1980, 282 p.)|
|Section one: Planning|
|Chapter 1: Introduction to wells planning|
In general, there are two types of wells: dug wells and drilled wells. The obvious difference between the two is the size of the holes. (See Figs. A and B).
Dug wells are sunk by people working down in the hole to loosen and remove the soil. They need to be at least 1 meter wide to give people room to work.
Drilled wells, on the other hand, are sunk by using special tools which are lowered into the ground and worked from the surface. These wells are normally less than 30 centimeters (cm) in diameter, and for the purpose of this manual, will usually be less than 15 cm. The reason for this is the difficulty of drilling larger holes with hand-powered tools.
In both categories, there are many different specific sinking techniques which will be discussed in more detail later.