The Ecological Dry Toilet

En español


The Centro de Innovación en Tecnología Alternativa, A.C. supervises the construction and maintenance of ecological dry toilets, cisterns for rainwater harvesting and wetlands for greywater treatment. Espacio de Salud, A.C. provides education, training and technical assistance for low-income grassroots groups in the management, treatment and agricultural use of household organic wastes. Both organizations promote a variety of environmentally-friendly alternatives in rural and urban settings.


¿Why talk about caca?

The urban sewage system perishes more from its successes than from its failures. Its greatest and maybe only exploit, is proclaimed by the name itself of "inodoro" (without smell): urban sewers and the w.c. have succeeded in removing the smell of caca which impregnated premodern cities. Furthermore - although historians are beginning to doubt this - it is attributed with having diminished the risks of cholerae and typhoid.

Ecologists are just beginning to evaluate its costs: destruction of aquatic life, contamination of aquifers and, in Mexico, the destruction of soil stability due to groundwater pumping.

The role of concealing remains: thanks to the "inodoro" and the sewer system, caca has been made almost invisible for the inhabitants of "nice" neighborhoods. But by hiding waste, sanitation – as experts call the sewer system and the collection of garbage - has made us impotent to confront waste. All cultures have made the broom into a magical symbol and that must be for some reason; the broom is an instrument of power over our vital space. Sanitation took from us the smell and the broom in one sweep.

Jean Robert



The Ecological Dry Toilet

Taking into account the wide variety of alternative toilet systems, we believe the double-vault dry toilet is the best option. Furthermore, it is easily adaptable to diverse cultural needs. It is important to observe two fundamental principles to guarantee correct functioning: urine diversion and adequate dessication in an alkaline environment.

indoor dry toilet

The dry toilet consists of two vaults: one in use and the other inactive. The Añorve model toilet seat facilitates the diversion of urine which passes through a hose and can be used as fertilizer by storing it for later use. The urine can also be sent to a shallow cavity to reintegrate the nutrients into the soil, thus fertilizing nearby vegetation.

The excrement, which falls into the chamber, must be covered with lime or ash and soil after each use. When the vault in use is almost full, the other is emptied, and ready for subsequent use. In this system, factors contributing to the destruction of pathogens are: lack of humidity, an alkaline environment and a lengthy storage period, achieved by the alternate use of the two vaults.

The ecological double - vault dry toilet presents the following benefits to its users: it saves water, is simple and inexpensive to install, requires little space, and can be installed inside or outside of the house. As an additional benefit, the user regularly harvests organic soil conditioner, free of pathogenic organisms, as well as a constant flow of natural fertilizer (urine).



Did you know that... and what’s more...
  • Almost half of the water consumed in an average house in Mexico is used for the W.C.?
  • Ecological dry toilets do not contaminate water.
  • A family of five who uses a water toilet contaminates more than 150 thousand liters of water to transport 250 liters of excrement in one year?
  • Dry toilets produce about 500 liters of dry fertilizer and 5000 liters of liquid fertilizer as they transform the excrement and urine of a family in one year.
  • Water toilets destroy aquatic life and contribute to the general scarcity of potable water.
  • A dry toilet can adapt to the possibilities and tastes of each family.
  • They can be installed inside or outside the house, and on second or higher stories of buildings. They can be built even where municipal water and sewage services are available. The dry toilet is not only an alternative in rural areas.











    Last updated on July 25, 2001