 | 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 |
F. Preventing water contamination
What is the optimum well design for the prevention of contamination?
The only way to design a well to prevent water contamination is to seal it so that water can enter only through the bottom section. Dug wells need to be covered with a permanent cover through which a pump is installed to draw water. All wells should have a platform around them that is at least 1 meter wide, one which water will not penetrate. This platform ought to be sloped in such a way that any spilled water runs off away from the well. (See Figs. A and B on inside of front and back manual covers.)
These and other measures are described in more detail in the design section for the different types of wells (pp. 23 and 124).
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