ceramic water filters

Background

While access to clean and affordable drinking water is considered by many as a human right, nearly 1.1 billion of the world's poorest people, those earning US $2 a day or less, are without adequate water services and access to safe drinking water (WHO, 2004).  In rural campesino communities of Guanajuato, Mexico access to clean water involves the lost time to access the source and costs $24 pesos (roughly US $2) for 20 Liters (L).  At this cost, the typical family of four members per household, each consuming approximately 5 L/person/day, would spend nearly $24 pesos (US $2) per day just on drinking water, or about US $0.10/L.  Drinking water, free of bacteria and pathogens (the number one cause of water related illness and death globally), is a human right that should made available to everyone affordably.  

How does it work?

Ceramic water filtration is being used around the globe as an inexpensive answer to potable water concerns.  Engineers at iCATIS designed the ceramic water filters used by Caminos de Agua.  Typical ceramic filters are large, pot-shaped bowls that sit in a plastic receptacle.  Our filters were designed by Dr. Robert Marquez with users in mind.  The filters are smaller, yet more robust than typical pot-filters, and they are made in an extremely simple mold as opposed to large mechanical presses.  Filter mixes are made from clay and a burn-out material (we uses waste sawdust); they are molded in a simple hand press and then fired in an MK 2 Kiln (a sustainable brick-kiln).  Filters are then treated with a colloidal silver solution and adapted to a system using locally appropriate materials. (Caminos de Agua uses a “garrafon,” or carboy, system with a 12/L ceramic base-receptacle).  

The filters produce approximately 24 liters/day, require minimal maintenance, last 2-3 years, and can reduce the cost of potable water from $0.10/liter to approximately $0.001/liter, or 100 times less expensive.  

Advantages:  

  1. Inexpensive, low-tech, and very effective in turbidity, bacteria, and pathogen removal (lab tests, both in-house and by 3rd parties, consistently show bacteria/pathogen removal at the no detect level); 
  2. Lighter, easier to transport, and less likely to crack or break than typical pot-filters;
  3. Simple filter mold encourages in-home filter businesses, transforming “employees” into “entrepreneurs;”
  4. Traditional pot-filter walls are .5”, while CATIS-Mexico filter walls are .7225” thick - giving a safety factor of 1.4
  5. Adaptable systems: can be made with materials appropriate to a specific region.
  6. When combiened with simple water harvesting systems (ferrocement catchment cisterns) already established in the region, Guanajuato residents take pressure off groundwater supplies, become autonomous in their potable water supply and create local business opportunities.  

Caminos de Agua is working with Northern Illinois University (NIU) and Engineers Without Borders-UK to create a low-cost filter “add-on” that can remove arsenic and fluoride, the problems that plague Guanajuato’s groundwater.  We have also developed relationships with other universities, namely The University of Tamaulipas in Tampico Mexico and The University of New Mexico, who are working on petroleum and radioactive removal add-ons, respectively.  These modifications will make the filter adaptable to long-term groundwater concerns around the globe.  

More than Technology: Opportunities for Microbusiness

Caminos de Agua sees the ceramic water filter as more than appropriate technology.  Working with local community groups, we are developing methodology to create local economic opportunities.  

Long-term development of micro-enterprise opportunities for local communities, include: 

  1. In-home filter molding businesses,
  2. Community-based system maintenance and/or assembly businesses, 
  3. Filter distribution,
  4. Filter replacement exchange program, and
  5. Increased economic opportunities for local brickmakers in the burning of raw filters.

Caminos de Agua has employed dozens of people from local campesino communities, several of whom remain full-time with us As we scale up, we have identified part-time and seasonal workers we hope to offer full-time employment to quickly and who can act as trainers and supervisors for future production and education.

Make your own! Videos on how to make your own system are now available in Spanish. Videos show how to make filter system with buckets and systems with carboys.

Ceramic Water Filters Resources