ECOSAN

Background

Waste management is one of the major challenges for developing countries like Nepal, where the waste generated is haphazardly dumped, is causing pollution to both surface and ground water sources. Consumption of contaminated water can cause various water borne diseases such as diarrhea, dysentery, typhoid, etc. The cases of water borne diseases are increasing, resulting in deaths of many children less than 5 years of age. Nonetheless, different technologies such as drainage systems, water treatment systems, sanitary landfill has been developed in various phases of time addressing these environmental and human health issues. But implementation of these technologies developed in the western countries demand huge investment and highly skilled man power mostly unavailable to developing countries. Therefore, 3 R Principal (Reduce, Recycle and Reuse) on waste management has been the most effective tool, providing ample opportunities to re-use of the waste as resources. Similar to woes of water resources, Nepals’ agriculture sector is also in grim situation. The excessive and continuous use of the chemical fertilizers for the higher production is not only deteriorating the soil fertility but also posing harm to human health. Instead, the use of natural fertilizers could best serve the need for sustainable farming and improve human health. In this context the concept of ‘Ecological Sanitation (EcoSan)’ has emerged as a solution to tackle both of these problems.

EcoSan is an environmental friendly sanitation technology, which acknowledges human urine and faeces as valuable resources for agricultural sustainability. Urine contains various elements such as nitrogen, phosphorus and potassium necessary for the plant growth. Human faeces also contains these elements though in lower concentrations along with organic matter essential for agricultural productivity. But unlike urine, faeces contains thousands of bacteria including pathogens. In this regard, in EcoSan toilets, urine and faeces can be collected separately for the use in agricultural field which is fruitful from both environmental and economic point of view. This makes EcoSan toilets different from the conventional toilets. Most of the EcoSan toilets being constructed at present are designed with two concrete chambers of equal volume for faeces collection and a plastic drum for urine collection. Normally, it takes six to seven months to fill one chamber for a family size of 5 to 6. Once one chamber is filled up with faeces, the second chamber is used. By the time this second chamber gets filled, the faeces collected in the previous chamber would be ready to be used as a soil conditioner. The time required to convert the faeces into soil conditioner ensures bacterial die-off. With an assumption of 1.5 L of urination from a person a day and a family size of 5-6 members, a container sufficient to collect urine for 10 days in average is used while constructing EcoSan toilet. The collected urine can either be used in agriculture or in compost preparation. The use of urine in compost increases degradation rate of compost and enhances its nutrient content.

Benefits of EcoSan

Use of NPK rich urine as a soil moisturizer.
Water conservation and low wastewater generation.
Decrease in monthly water bills and chemical purchasing cost.
Environmental and water resources conservation.

Limitations of EcoSan

Uncomfortable to use in the beginning as the design is different from the conventional toilets.
Reluctance in acceptance and use.
Lack of farming land limits the application of urine and faeces.