Ecological sanitation for rural communities

Here is a new and holistic approach to the concept and management of human excreta, which includes urine-diverting and no-flush toilets for individual households

It is difficult to get anyone interested in ecological sanitation. Most people dislike talking about faecal matter and defecation. However, Britisher Paul Calvert, director of Eco-Solutions, with his pioneering work in the field of ecological sanitation has shown that it is possible. He spends about six to eight months in Thiruvananthapuram and focuses on implementing the project in the coastal area there. An experiment to make it a community toilet met with failure, though – there was no feeling of ownership or discipline in implementation. Also, many of the women probably liked a latrine at home. SCOPE, an organisation in Tiruchy headed by Subbaraman has also been implementing the project in villages on the banks of the Cauvery. A lot of good work on sanitation has also been carried out in many of the fishing villages in Kerala.

Now, what is a dry-compost ecological toilet? The dry-compost ecological toilet separates and sanitises human excreta, produces a useful soil improver that can used as manure and prevents contamination of groundwater. It has proved to be particularly popular in areas where the groundwater table is shallow. In nature, nothing constitutes waste and one form of waste is food for another. Hence, the natural cycle includes growing food, consuming food, defecating, and returning excreta to the soil.

Ecological sanitation is a sustainable closed-loop system, states Calvert, Ajith Seneviratne, DGJ Premakumara and Udani A Mendis, writing about a Sri Lankan success story in an issue of Waterlines. In contrast to most applications of conventional sanitation, which in many situations discharge pathogens (tiny agents causing disease in humans) and nutrients into groundwater, rivers, water bodies and the sea, ecological sanitation regards excreta (comprising urine and faeces) in a different light, considering it a resource rather than a waste.

Ecological sanitation, thus, sanitises human excreta, making it safe by killing the pathogens it may contain; it prevents pollution of rivers, sea, groundwater and waterbodies, minimises water use, safely recycles the valuable plant nutrients that are contained in our excreta, and helps produce excellent quality manure.

Modern toilets, both Indian and Western, are not ideal for eco-sanitation purposes, says Sekhar Raghavan, director, Rain Centre, which is now promoting ecological sanitation in Kovalam, a semi-urban area about 30 km from Chennai. The 1970 batch of IIT Madras has provided the Centre a grant, one-third of which will be used for eco-sanitation and the remainder for rainwater harvesting. According to Raghavan, modern toilets create effluent and people either do not know how to handle it or are forced to go in for expensive sewage treatment plants. Residents in smaller towns and cities use water for flushing and also do not know what to do with the effluent, which is ultimately discharged into available water bodies. They do not realise that they are polluting both the surface and groundwater.

So, people who reside in independent houses with a little bit of garden area in semi-urban or peripheral areas of cities - towns such as Villupuram and Tindivanam – could go in for the dry-compost toilet. The toilet works only if you have some open space. It is actually a two-pit latrine, with an independent chamber below each. After squatting and defecating, the person dumps a handful of ash or soil (contains bacteria) down the pit; there is a separate outlet for urinating. Dry toilets do not mean that you do not wash; washing is done a little distance away to ensure that no water enters the pit. A small rim placed around the pit does not allow seepage of water into the pit, although, Raghavan adds that a few drops of water falling in does no harm. The faecal matter is contained, without odour in the chamber beneath the toilet where its volume is reduced by dehydration or decomposition and the pathogens are destroyed.

The urine that is diverted at source and escapes through a separate outlet mixes with the wash water and can be channelled to water plants. Urine is an excellent substitute for urea, contains nitrogen, potassium and phosphate, and can be fed directly into biomass. Plants such as banana, coconut, vegetables, flowers or plants for fuel wood may be grown.

Only one pit is used for defecating. When this pit gets almost full (usually takes 6-8 months if used everyday by a family of four or five and, depending on usage, the size of the pit can be increased), soil and ash are used to fill and close it semi-permanently. Residents now switch over to the other pit. By the time the second pit is filled, the first pit would have got composted. The compost is removed from one side of the chamber below and applied as soil improver or manure on plant beds or used for horticulture. “The compost has no bad smell; it is smooth and silky, and there are no flies at all,” Raghavan points out.

Raghavan adds that the dry-compost toilet is used worldwide, particularly in China where 40-45 percent of toilets are of this type. It is rapidly becoming popular in Europe, USA, Australia and Scandinavia too.

Raghavan decided to use a fishermen’s hamlet to launch the exercise in rural Tamil Nadu. He chose Kovalam along Chennai’s famous East Coast Road. One such toilet was constructed and readied for use in January this year and Raghavan has received a few calls since, seeking help to construct similar toilets. One-third of the cost of such toilets is usually met by residents.

(With inputs from the Rain Centre, Chennai (Ph: 24616134) and Eco-Solutions (