the rope pump team

there was actually a third team in the engineering class where I mentored the clean stove and treadle pump teams.  they worked on an interesting project as well, and since they were kind enough to share their results and documents with me, I would like to do a couple posts about them too.

like the treadle pump team, the rope pump team concentrated on ways of getting clean water to people for drinking and farming.  on average, a human being can only survive 3-5 days without water, but in many developing areas, there is little safe drinking water.  therefore people will drink whatever is available, including dirty rivers, contaminated open water, standing water and other sources rife with water-borne illnesses.  worldwide, more than 1 billion people do not have access to safe drinking water, and water-borne diseases are estimated to cause more than 2 million deaths annually (2007, American Journal of Tropical Medicine and Hygiene)

"Millions of people all over the world, especially in rural Africa, live many kilometers from a reliable source of clean water, leaving them vulnerable to cholera, dysentery, and other water-bourne diseases.  We have all seen pictures of women and children in developing countries carrying heavy containers of water, mostly on their heads; this labor invariably causes many neck and spine injuries." -- Rolling Water, Design for the Other 90%, 2007

 

imagine using a simple rope to move water up from under the ground.  tie a few knots in it and stick it in a pipe.  circulate the rope through the pipe, and the knots draw up water for drinking or farming.  that’s the basic premise of a rope pump.

the students on this team developed a rope pump design that is easily built and maintained, and has clear available instructions so that anyone can create it.  their design goals were to be able to pump at least 5 gallons per minute from up to a 20 meter depth, for less than $100.  key parameters beyond the usual safety, quality, and reliability of a well-engineered product included low operating effort so that women and children would be able to operate the pump, and minimal maintenance. 

next time:  what is a rope pump, exactly?