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Here you can see two inexpensive methods of harvesting and holding rain water.  "Earth Tank" systems designed to serve individual families as well as regular tank systems designed to serve schools or entire villages are innovated and built by RDI.   Rainwater harvesting is a cost effective way of using natural resources to provide safe, arsenic-free drinking water.
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Above are photos of ball tanks in use by area villagers, and a newly installed ball tank at a local school.
Earth Tank System Overview - detailed view

For only $75 RDI can build a 4,200 liter "Earth Tank" for a rural family.  RDI developed this innovative structure and is inviting visiting teams to come out and build these tanks for needy families.

How does it work?

  1. Gutters are added to existing roofs of houses.  (Where needed, a metal roof is offered.)
  2. A PVC pipe is run from the gutter to the sphere tank. 
  3. During the rainy season, the tank fills up, giving a typical family of 6 enough water for an entire dry season.
  4. Water is collected out of the spigot.
  5. (The water can also be sent through the clay filter system at this step.)
  6. Drink up!

PROS: Inexpensive, very easy to clean (no corners means less breeding ground for bacteria), enclosed design makes it hard for mosquito larvae and solids to contaminate the tank, light cannot get in which prevents algae growth and reduces food supply for dangerous pathogens, maximum structural strength with the least amount of materials, can be moved if necessary

CONS: Compared to other rural mass water storage structures?  None.  However, no system of clean water delivery is complete without education coupled with the technology. 

For further information about Earth Tank construction and implementation click here!

 

RDI is unique in that a steady series of personal follow-up visits are given to recipients of harvest systems, filters, etc.  Making sure the family learns about using clean bowls, jugs, pans, etc to collect the water is essential.  No single technology will ever be a solution in itself, and RDI is committed to a holistic approach to solving overall health issues to the people of Cambodia.



By adding our ceramic (shown) or Ultra-Violet filters, a complete system is ready for community use.
Cylinder tanks are often constructed by visiting teams, on site at rural schools along with hand washing stations and drinking water stations. 



 
Cylinder Tank System Overview

20,000, 30,000 and even 50,000 liter tanks can be built for use by entire communities. A 30,000 liter rainwater tank can harvest enough water to get a typical large Cambodian school through the dry season.  Costs vary, but a 30,000 tank requires roughly $1000 in materials and labor.

How does it work?

  1. Gutters are added to the roofs of nearby buildings.  (Where needed, a metal roof is offered.)
  2. PVC pipe is run from the gutter to the cylinder tank.
  3. During the rainy season, the tank fills up.
  4. Water is diverted to hand washing stations, into various outdoor filters for drinking water, toilets, or misc. water spigots.
  5. (Depending on the location, a series of clay filters or the ultra-violet light filtration system may be employed to further purify the drinking water.)
  6. Clean water is used!

PROS: Stores huge volumes of low-risk drinking water; gives access to entire communities or schools to what would be wasted high quality water, enclosed design makes it hard for mosquito larvae and solids to contaminate the tank; light cannot get in which prevents algae growth and reduces food supply for dangerous pathogens

CONS: Without additional enclosure it is susceptible to vandalism, rising costs of materials makes it a more and more expensive venture
 

NOTE: Rural schools are often the center of the community and provide an excellent location for a community water supply.  Conveniently, this is also where RDI can do health education (live presentations and puppets) during classroom hours.  Visiting teams can also be integral to education as well as building and are encouraged to help RDI implement these systems in all of Cambodia.