[[Image:Treadle_pump_icon.png{{Language-box|right]]english_link=Sludging - Baptist method | french_link= Coming soon | spanish_link= Coming soon | hindi_link= Coming soon | malayalam_link= Coming soon | tamil_link= Coming soon | swahili_link=coming soon | korean_link= Coming soon | chinese_link=浸会钻井法 | indonesian_link= Coming soon | japanese_link= Coming soon }}
[[Image:Icon_sludge.png|right|80px]][[Image:Baptist drilling.jpg|thumb|right|200px|Baptist drilling rig in operation. Note the drilling mud gushing out of the drill pipe.]] [[Image:Baptist_drilling2.jpg|thumb|right|200px|Baptist drilling rig in operation. <br> Click image to zoom in.]] [[Image:Baptist_drilling_start.jpg|thumb|right|200px|Starting a Baptist drilling.<br> Click image to zoom in.]] [[Image:Drill bits and valves.jpg|thumb|right|150px200px|Drill bits and valves]] __NOTOC__
The Baptist method is a manual drilling method based on the [[Sludging - Asian sludge|Asian Sludge method]]. The method was developed to be used by very poor villagers in developing countries, who quickly learn how to drill their wells themselves. The Baptist drilling rig can be built in any ordinary arc welding workshop and materials for a basic version costs about 150 US$ (2006 prices).
==History and social context==
The method was developed by Terry Waller, a North American Baptist missionary, in Africa and Bolivia. It applies some of the same principles used in mechanized commercial well drilling, but does so using the simplest, most available and cheapest possible materials.
Rural people in developing countries often cannot afford to have specialists drill or dig wells for them. This method was developed to provide poor people with a way to help themselves with their water supply. Having built their own well and pump, users become independent from external help for their water supply.
===Suitable conditions ===
Suitable for unconsolidated formations: Sand, silt and clay. If rotated (including a drill bit) it may be possible to penetrate softer-consolidated formations such as stiff clays, soft sandstone, and weathered laterite. It will not, however, penetrate hard [http://en.wikipedia.org/wiki/Igneous igneous] rock or [http://en.wikipedia.org/wiki/Boulder boulders] (e.g. in ancient river beds).
In the unconsolidated formation types of Bolivia wells are drilled to depths of 20 and 60 meters on average. In the consolidated formations of Nicaragua, Ethiopia and Kenya well depths range from 10 – 15 meters on average. In exceptional conditions, boreholes up to 100 m deep have been drilled with this method.
{{procontable | proborder="1" cellpadding="5" cellspacing="0" align="center"|-! width="50%" style="background:#efefef;" | Advantages! style="background:#f0f8ff;" | Disadvantages|-| valign="top" | - Very simple and cheap equipment. <br>
- Easy to handle and a temporary casing is normally not needed. It is possible to construct the drilling equipment locally.<br>
- continuous movement (compared to [[Hand auger - general|augering)]])
- small diameter borehole possible <br>
- Does not clog quickly in clay soils - No need for mud pump and tower <br>
- Caving resistant borehole <br>
- Possible above and below the water table
|convalign= "top" | - The borehole stays open by water pressure. To prevent collapsing, fluid-drilled boreholes must be kept full of water during the entire drilling and well installation process.<br>
- Coarse gravel and other highly permeable materials (cracks in the formation) cause loss of working water and cannot be drilled. If very fine sands (quick sands) are encountered in the first three meter of the borehole, a temporary casing and swell clay are needed on the outside of this casing to prevent collapse.<br>
- Suitable for unconsolidated rocks only (sand, silt, clay)<br>
- PVC drill stem needs to be of high quality<br>
- In wells deeper than 20m, a lot of manpower is needed to pull the rope
}|}
===Construction, operations and maintenance===
[[Image:Baptist_drill_bit.jpg|thumb|right|200px|Baptist drill bit. The arrow-shaped point is mounted on a ball, which acts as a check valve. The mud, loaded with clippings, passes the check valve and is carried up during the downward motion of the drilling stem. Depending on the type of soil, different drill bit designs are used.]]
[[Image:mechanized.jpg|thumb|right|200px|Mechanized version of Baptist drilling, powered by a 3HP diesel engine.]]
==Technical specification==
[[Image:Baptist_drill_bit.jpg|thumb|Baptist drill bit. The arrow-shaped point is mounted on a ball, which acts as a check valve. The mud, loaded with clippings, passes the check valve and is carried up during the downward motion of the drilling stem. Depending on the type of soil, different drill bit designs are used.]]
[[Image:mechanized.jpg|thumb|Mechanized version of Baptist drilling, powered by a 3HP diesel engine.]]
====Operation====
The Baptist drilling process work with pure impact action, there is no rotating movement. Because there is no torque on the drilling stem, a light drilling stem can be used, such as thick-walled PVC pipe. The light drilling stem permits pulling the tool up with a simple pulley fixed to any kind of tripod or crossbeam.
* Open-ended (hollow) bits without a footvalve (pure sludging) for layers of pure clay or gravel. In these conditions the presence of a footvalve may slow down progress, since clay has to be pounded into suspension and stones have to be ground to small pieces in order to enter the drilling tool through the footvalve.
====Reaming====
If required, the upper part of the well can be reamed and cased with larger diameter pipe (3 or 5 inches), to accommodate larger pumps. A shallow (large diameter) [[rope pump]], for example, may require a wider well (although small-diameter rope pumps can fit in a 2" borehole), and submersible pumps commonly need at least 4".
Note that there is no need to enlarge the entire depth of the borehole: reaming until slightly below the lowest expected water table (the pump's water intake) is sufficient.
===Costs=Maintenance==== ====Manufacturing ==== ==Cost==
A Baptist drilling rig, fit to drill holes up to 30 m deep, can be built in Nicaragua for about US$ 150. This includes all essential non-common tools to operate it. Its core element, the drill bits, can be made in about any arc-welding workshop, using only scrap steel and materials that can be found in virtually any hardware store.
Once the well is drilled, it is cased with cheap PVC tube. Fitting it with a slab of concrete as a sanitary seal and a simple PVC piston pump (also built by the users themselves) will cost about 2.5 dollars per meter well depth.
==Country =Field experiences===
Baptist well drilling is used in Bolivia, Nicaragua, Kenya, Ethiopia, Mozambique, Cameroon, Zambia and Sri Lanka.
===Manuals, videos and links===* [http://www.arrakis.nl/filesview-more/Baptist%20drill%20%20manual%20%20%20Shipo%2010baptist-08well-08%20lo%20resdrilling-1.doc] technology Baptist drilling manual], by [http://www.arrakis.nl/ Arrakis] ==Movies / Media==* [http://www.youtube.com/view_play_list?p=370A3B99269BC4FE Complete set of movies on Baptist well drilling], compiled by Paul Cloesen. * [http://waterforallinternational.org/videos.aspx Video on Baptist well drilling] on Water for All international.
* [http://waterforallinternationalwww.orgyoutube.com/Documents/WFA%20Bolivian%20Baptist%20Drilling%20System.pps Powerpoint presentation view_play_list?p=370A3B99269BC4FE Set of 9 movies on Baptist Drillingwell drilling] , compiled by Terry WallerPaul Cloesen.
* [http{{#ev:youtube|KJSkDXu4LE8|200|auto|<font size="2"><center>Low cost Baptist well drilling</center></waterforallinternational.org/media.aspx Photos from the Field], by Water for All.font>}}
== Acknowledgements==* The basis for the material on this page was obtained from a desk study shortly to be published on the website of the [http://www.practicafoundationwaterforallinternational.nl/ Practica Foundation], and from the [http:org/Documents/wwwWFA%20Bolivian%20Baptist%20Drilling%20System.rwsn.ch/ Rural Water Supply Network], and specifically its [http://www.rwsn.ch/prarticle.2005-10-25.9856177177/prarticle.2005-10-26.7220595116/prarticle.2005-11-15.6127855822 manual drilling sectionpps Powerpoint presentation on Baptist Drilling]by Terry Waller.
==External Links==* [http://www.waterforallinternational.org/drillingoverviewPages/media.aspx Photos from the Field], by Water for All - Website of Terry Waller on Baptist well drilling] * [http://www.arrakis.nl/view_more.php?page=baptist_well_drilling_technology Baptist well drilling, article by Arrakis]
* Rural Water Supply Network, [http://www.rwsnwaterforallinternational.chorg/prarticle.2005-10-25.9856177177Pages/prarticledrillingoverview.2005aspx Water for All -10-26.7220595116/prarticle.2005-11-15.6127855822/prarticle.2009-05-11.3051371225/prarticle.2009-05-11.7179743538 article Website of Terry Waller on Baptist well drilling]. General [http://www.rwsn.ch/prarticle.2005-10-25.9856177177/prarticle.2005-10-26.7220595116/prarticle.2005-11-15.6127855822/prarticle.2009-05-11.3051371225 manual drilling section of RWSN website].
*Rural Water Supply Network, [http://www.arrakisrural-water-supply.nlnet/en/implementation/filesmanual-drilling/Oxfam_DAPP%20drilling%20trial%20report.pdf OXFAM trial study 167-baptist-drilling article on the use of the Baptist drilling method in Zambia, DAPP]. General [http://www.rural-water-supply.net/en/implementation/manual-drilling manual drilling section of RWSN website].
* Technical note 43. Simple drilling methods, Bob Elson and Rod Shaw, WEDC - An overview of simple drilling methods [http://www.lboro.ac.uk/well/resources/technical-briefs/43-simple-drilling-methods.pdf Download]. Website of [http://www.lboro.ac.uk/well/resources/technical-briefs/ Loughborough University Technical Briefs section]. Website of [http://www.lboro.ac.uk/well/ Loughborough University WELLS].
*[http://es.wikipedia.org/wiki/Perforaci%C3%B3n_Bautista_de_Pozos Spanish Baptist well drilling article on Wikipedia].
==References==* The [http://en.wikipedia.org/wiki/Baptist_well_drilling Wikipedia article on Baptist Drilling[Solution_of_the_week_4|Akvo solution of the week 4]], orginally written by Paul Cloesen.
{{Joinus}}=== Acknowledgements===* The basis for the material on this page was obtained from a desk study shortly to be published on the website of the [http://www.practicafoundation.nl/ Practica Foundation], and from the [http://www.rwsn.ch/ Rural Water Supply Network], and specifically its [http://www.rural-water-supply.net/en/resources/details/653 Manual Drilling Compendium 2015].* The [http://en.wikipedia.org/wiki/Baptist_well_drilling Wikipedia article on Baptist Drilling], originally written by Paul Cloesen.* [http://www.lboro.ac.uk/well/resources/technical-briefs/43-simple-drilling-methods.pdf 43. Simple drilling methods.] WEDC.
