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

H. Well sections

Every well, whether drilled or dug, has three sections: top, middle, and bottom. Each of these sections varies in construction, because each must function differently. (See Figs. A and B.)

• Top section - That part of the well at or above the ground surface level. It should be designed to allow people to get water as easily as possible, and, at the same time, to prevent water, dirt, and other contaminants from entering.

• Middle section - That part of the well which is between the ground surface and the water, This section is usually a circular hole. It is reinforced with some kind of lining to prevent the walls from caving in.

NOTE: Lining and casing refer to the same part of the well (see Figs. A and B). Lining is used to refer to that part of the dug well, while casing refers to the pipe used to reinforce a drilled well.

• Bottom section - That part of the well that extends beneath the water table into the aquifer. It should be designed to allow as much water as possible to enter, and yet prevent the entrance of any soil from the aquifer. Its lining will have holes, slots, or open spaces, allowing water to pass through.