On sustainable sanitationMay 25, 2010
Study this plant fertilizer – Using sanitation for crops
|Eco-san creates toilet systems which separate solids and liquids at source and treats them before they are applied on soil as a nutrient|
As sanitation involves water, this week’s ‘Waterwise’ series brings you details on how the nutrients in human wastes can be converted into manure for growing greenery.
Eco-san is a shortened term used to describe Ecological sanitation, a system of sanitation which seeks to handle human wastes safely and in a hygienic manner without causing pollution and using the nutrient value contained in the waste for growing plants.
It is well recognised that bad sanitation systems not only cause health problems but also pollute the environment dramatically. In Bangalore, ground water to depths of 400 feet has been polluted with nitrates, according to a Department of Mines and Geology study. Up to 70 per cent of the wells studied had excess nitrate in them.
A study of several wells in the Koramangala and Challaghatta valleys of Bangalore by the State Pollution Control Board also reported severe contamination.
All this pollution came from domestic sewage and bad sewage systems. This also has the effect of rendering the abundantly available groundwater unfit for any use, thus creating a shortage of water.
Eco-san tries to address the situation by creating toilet systems which separate solids and liquids at source, use urine as a fertilizer for plants and compost the faeces to remove pathogens before being applied on soil as a nutrient.
The Indian style Ecosan pan is designed with three openings. One for the urine, one for the solids and one for ablution purpose. All three are disposed of in different ways. The urine can be collected in barrels and then used as a fertilizer or it can be led into a vegetable patch directly. This applies to ablution water too.
The solids are composted in situ by designing two boxes. When one box is full the pan is shifted to the other box.
After every use of the toilet the solids are covered with ash or sawdust or any organic material.
This ensures no smell. This pan is being made in Bangalore by N-Fibro Systems in Rajajinagar.
The Eco-san movement has rapidly spread and taken root in many parts of the world.
In India too, pioneers such as Paul Calvert ( www.eco-solutions.org) have demonstrated its application in high water table areas of Kerala, Tamil Nadu and Karnataka and many other places.
These applications have mostly been in rural places with a few exceptions.
In an urban context, in a school in Dodballapur (population 100,000), an eco-san toilet has been built by several partners led by the group Waste wise.
The school children have received training in its correct use.
Farmers are using the urine generated for applications in maize, banana, lemon and papaya plantations.
Western-style Ecosan WCs are yet to come to India in a significant way but are available in countries such as Mexico and South Africa. As time goes they should become available here too.
Through a combined strategy of application and construction, communication, research and finding, funding urban eco-san can be pushed as one solution to the critical problem of groundwater contamination, especially through nitrates, in cities such as Bangalore.