 | Wells construction: hand dug and hand drilled |
 |  | Acknowledgments |
| | Introduction |
|  | Section one: Planning |
| | Chapter 1: Introduction to wells planning |
| | A. Overview |
| | B. The need for adequate water supply |
| | C. Involving the local community |
| | D. Selecting the most appropriate water source |
| | E. Site choice |
| | F. Preventing water contamination |
| | G. Types of wells |
| | H. Well sections |
| | I. Materials |
| | J. Tools and equipment |
| | K. Sinking method |
| | L. Preparation for construction |
| | M. Planning |
| | Section two: Hand dug wells |
| | Chapter 2: Introduction to hand-dug wells |
| | Chapter 3: Well design |
| | Chapter 4: Supplies |
| | Chapter 5: Lowering and raising workers and equipment |
| | Chapter 6: Digging |
| | Chapter 7: The middle section: overview of lining techniques |
| | Chapter 8: Construction of the middle section |
| | Chapter 9: Construction of the bottom section |
| | Section three: Drilled wells |
| | Chapter 10: Introduction to drilled wells |
| | Chapter 11: Drilling and casing techniques |
| | Chapter 12: Construction: hand rotary and hand percussion methods |
| | Chapter 13: Construction: sludger method |
| | Chapter 14: Construction: driven and jetted |
| | Chapter 15: The bottom section |
| | Appendices |
| | Appendix I: Conversion factors and tables |
| | Appendix II: Vegetation as an index of ground water |
| | Appendix III: Uses of dynamite in hand dug wells |
| | Appendix IV: Cement |
| | Appendix V: Leveling and plumbing the mold |
| | Appendix VI: Pipe |
| | Appendix VII: Pumps |
| | Appendix VIII: Water treatment in wells |
| | Appendix IX: Rope strength |
| | Glossary |
| | Annotated bibliography |
G. Types of wells
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.
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