On the toilet trail: Making disposal easy
1 Oct 2014 9:16 PM GMT
Jokes on Delhi belly are hardly funny to the concerned Indian, given that it is an embarrassing reflection of poor sanitation. The inability to meet the Millennium Development Goal commitments, the astounding levels of anemia and stunting all point to the same deficiency: deplorable sanitation. Why is this the case? Are solutions possible?
Sanitation got a much-needed focus when Prime minister Modi declared that by 2019, India would attain the status of Swachchh Bharat. The goal is ambitious- it is also preponed from the earlier deadline of 2022- but it may just be possible. But for this to happen, an understanding of the prevailing scenario is first needed.
While the issue needs to be addressed on multiple fronts, one major drawback in the current scenario is absence of the provision of end-to-end solutions. Rather than pumping in the much-needed extra funds, a model that is workable needs to be found, one that offers a complete and sustainable solution. And, in spite of consistent failures and the adoption of part solutions, this is possible.
Build and forget
In rural India and urban slums, toilets are constructed with little afterthought about their care, upkeep and maintenance. Toilets often end up-crudely put- as offering a passage of shit from one part of the house to another, becoming a source of stink and a breeding ground for mosquitoes and flies, and water leaching, which is a source of serious contamination. In such cases, one of the main purposes- that of improving health- is defeated.
Peri urban areas, mid size cities and slums and rural areas can share the same set of solutions, since challenges are common. In the former, the challenges are of space shortage for defecating and even if toilets are constructed, where does the waste go? In rural areas, toilets do not exist, and if they do, these are not used because (a) People remain unconvinced about the benefits; (b) Construction is faulty; (c) Water is unavailable for cleaning purposes; (d) O and M does not take place; and(e) Options for pit cleaning are limited.
Even if septic tanks are provided, these are seldom cleaned and become a solid waste disposal pit, remaining as a part of the house for years- again a source and breeding ground of disease. This is a pity since the use of septic tanks have great potential (see Box Septic tanks: A neglected option). In the US for example, according to an EPA 2009 report (Septic systems fact sheet), in 2007, an estimated 20 per cent (26.1 million) of total US housing units were served by septic systems. Many municipalities have framed by-laws and rules governing the septic tank provisions, design and Operation and Maintenance (O and M). In India, while BIS cods are framed for large septic tanks, there is a need to frame guidelines and by-laws for individual household (HH) septic tanks in urban and rural areas.
Changing the sanitation landscape
It is important that the solutions be (a) Cost effective and safe; (b) Generate local employment and entrepreneurs; and, (c) Provide dignified and safe employment to persons involved in excreta management. Because shit happens, and cannot be wished away, or washed away into waterbodies or left in the open.
Based on self-experience, field studies, interaction with various groups involved in sanitation and research on ferro-cement toilets and septic tanks, a business model is proposed for consideration for entrepreneurship development.
The advantages of using ferro-cement toilets include (a) Low cost; (b) Durability, (c) Clean tehnology, (d) Quality control- one point of quality control, and (e) Standardisation of sanitation system.
The model looks at providing total solutions: Providing toilets and mechanised fecal sludge management (FSM) services. The economics are calculated for providing services to 1,200 households (HH).
The business has two components: Provision of toilets and FSM services. The model can be adopted in rural areas and for urban mid-size cities and slums and wherever a sewerage system is not available. In rural areas, 1,200 HH will be provided with a toilet and septic tank within a 25 km radius. This septic tank can be cleaned once in a year.
The model therefore looks at the development of two entrepreneurs- one for constructing the ferro-cement toilets and the other for the FSM business. For the FSM business, those already involved in excreta management should be the first choice for supporting them develop as entrepreneurs, since they have knowledge and experience in excreta disposal and this business. Given that no manual handling of excreta will take place, their dignity will be upheld.
During the first stage, Entrepreneur I sets up the ferro-cement toilet and septic tank unit and constructs 1,200 toilets and septic tanks in the first year. The investment required to set this up is around 3.5 lakh which can be availed of as an SME loan.
Total cost of construction of 1,200 toilets is Rs 2.4 crore which can be accessed from available government funds, donors and the community. For this, the entrepreneur needs to generate demand through raising awareness and strategic marketing and leveraging government funding.
This entrepreneur will also build in profit for himself/herself in this cost. This implies that with an investment of Rs 3.5 lakh, entrepreneur I will have generated business worth around Rs 2.4 crore if he succeeds in building 1,200 toilets. The government also provides for up to Rs 20 lakh for solid and liquid waste management, which can be availed of.
Entrepreneur II buys a 5 ton truck and uses it to transport toilets and septic tanks and also fixes these. Total investment required to start and maintain an FSM business is Rs 10 lakh, which can be sourced as loans from banks.
After a year, Entrepreneur II transforms his truck chassis to a tanker mounted sludge tanker (3,500 litre capacity) and water tank (1,000 litre capacity) starts FSM services after a year with the use of sludge pump, water pump, air compressor.
Financial modeling indicates that it is possible for entrepreneur II to have a payback period of 30 months with a salary of Rs 16,000 per month and subsequent earnings of Rs 46, 000 per month.
A multi-party agreement between the state govt, NGO, entrepreneur and the user can be executed to prevent leakage and ensure commitment to sanitation and hygiene and the economic model.
The model is based on certain assumptions:
Business includes FSM and provision of ferro-cement toilets (base only, not superstructure) and septic tanks
1,200 households will be provided with a toilet and septic tank. This septic tank is cleaned once in a year
Septic tanks of around 1,000 litre capacity
Cost of toilet + septic tank = Rs 20,000. This includes cost of construction, cartage and profit.
Four septic tanks are cleaned daily.Tanks are cleaned once a year. Rate of cleaning = Rs 1,200. Radius of operation in rural areas= 25 km
Number of users per toilet = 8. Initially one toilet can be shared between two families or two HH, which means that 2,400 families will be served. This also means that the maintenance cost drops 50 per cent, to Rs 50 per HH.
Linking bathrooms
Where bathrooms exist, the wastewater generated can be connected to the septic tank. Here arrangements need to be made to dispose the supernatant. These tanks can be cleaned once in three years.
In small towns, which are not connected to the sewerage system, in absence of regular cleaning, these septic tanks can become a nuisance. Solidification will take place over time, reducing the capacity of the tanks. Thus, till such time the septic tanks are connected to the sewerage system, these tanks need to be cleaned once a year.
Final septic water and sludge disposal
The final wastewater generated can be diverted into a reed bed aerobic cleaning system. At present wastewater from septic tanks from the HHs is not linked to sewerage system and as a result, is allowed to spill over- not a healthy practice. This needs to be disposed in a scientific manner.
Till such time, septic tanks are connected to a sewerage system these tanks need to be cleaned annually, if not sooner, instead of once in 3 years or before these start overflowing. If there is a piped water supply and flushing system, septic tanks will start overflowing with wastewater sooner rather than later.
If there is no proper wastewater disposal system, it requires pumping and cleaning more frequently, which means additional business for the FSM service provider!
The sludge can be disposed of by composting with other appropriate waste material and used for agricultural and horticultural purposes.
Testing of model
The above model needs to be replicated in at least four different regions to understand the dynamics and challenges involved during implementation, so that corrections can be made for widespread replication. But it is a model that offers a total solution and options for livelihood development.
Septic tanks: A neglected option
Septic tanks are the first step in the process of sewage conditioning, in a subsurface disposal system. The importance and function of the septic tanks is commonly disregarded, yet science and experience proves its importance.
Septic tanks collect and treat wastewater; separate sewage into three different zones: sludge, scum (floaters) and clear zone in the middle. It allows for anaerobic digestion of organic matter. While anaerobic digestion does not remove disease-causing organisms, it reduces the biological oxygen demand, total suspended solids, fats, oils and greases. The removal of disease causing microorganisms occurs in the subsequent steps when the supernatant is disposed in an aerobic drain field system.
As a final stage of disposal, the treated effluent from the septic tank is discharged to the leach field where it percolates through suitable ‘septic zones’ and finally into the subsoil for further purification.
The functioning of septic tank is correlated to the design, usage, its correct size for occupancy and long term storage of the sludge. Settling of solids and flotation of scum requires a calm glow to promote growth of bacteria. A proposer design and functionality is critical in improving the effluent quality leaving the tank.
Ashok Khurana is a retired Director General, Central Public Works Department, Govt of India
Sanitation got a much-needed focus when Prime minister Modi declared that by 2019, India would attain the status of Swachchh Bharat. The goal is ambitious- it is also preponed from the earlier deadline of 2022- but it may just be possible. But for this to happen, an understanding of the prevailing scenario is first needed.
While the issue needs to be addressed on multiple fronts, one major drawback in the current scenario is absence of the provision of end-to-end solutions. Rather than pumping in the much-needed extra funds, a model that is workable needs to be found, one that offers a complete and sustainable solution. And, in spite of consistent failures and the adoption of part solutions, this is possible.
Build and forget
In rural India and urban slums, toilets are constructed with little afterthought about their care, upkeep and maintenance. Toilets often end up-crudely put- as offering a passage of shit from one part of the house to another, becoming a source of stink and a breeding ground for mosquitoes and flies, and water leaching, which is a source of serious contamination. In such cases, one of the main purposes- that of improving health- is defeated.
Peri urban areas, mid size cities and slums and rural areas can share the same set of solutions, since challenges are common. In the former, the challenges are of space shortage for defecating and even if toilets are constructed, where does the waste go? In rural areas, toilets do not exist, and if they do, these are not used because (a) People remain unconvinced about the benefits; (b) Construction is faulty; (c) Water is unavailable for cleaning purposes; (d) O and M does not take place; and(e) Options for pit cleaning are limited.
Even if septic tanks are provided, these are seldom cleaned and become a solid waste disposal pit, remaining as a part of the house for years- again a source and breeding ground of disease. This is a pity since the use of septic tanks have great potential (see Box Septic tanks: A neglected option). In the US for example, according to an EPA 2009 report (Septic systems fact sheet), in 2007, an estimated 20 per cent (26.1 million) of total US housing units were served by septic systems. Many municipalities have framed by-laws and rules governing the septic tank provisions, design and Operation and Maintenance (O and M). In India, while BIS cods are framed for large septic tanks, there is a need to frame guidelines and by-laws for individual household (HH) septic tanks in urban and rural areas.
Changing the sanitation landscape
It is important that the solutions be (a) Cost effective and safe; (b) Generate local employment and entrepreneurs; and, (c) Provide dignified and safe employment to persons involved in excreta management. Because shit happens, and cannot be wished away, or washed away into waterbodies or left in the open.
Based on self-experience, field studies, interaction with various groups involved in sanitation and research on ferro-cement toilets and septic tanks, a business model is proposed for consideration for entrepreneurship development.
The advantages of using ferro-cement toilets include (a) Low cost; (b) Durability, (c) Clean tehnology, (d) Quality control- one point of quality control, and (e) Standardisation of sanitation system.
The model looks at providing total solutions: Providing toilets and mechanised fecal sludge management (FSM) services. The economics are calculated for providing services to 1,200 households (HH).
The business has two components: Provision of toilets and FSM services. The model can be adopted in rural areas and for urban mid-size cities and slums and wherever a sewerage system is not available. In rural areas, 1,200 HH will be provided with a toilet and septic tank within a 25 km radius. This septic tank can be cleaned once in a year.
The model therefore looks at the development of two entrepreneurs- one for constructing the ferro-cement toilets and the other for the FSM business. For the FSM business, those already involved in excreta management should be the first choice for supporting them develop as entrepreneurs, since they have knowledge and experience in excreta disposal and this business. Given that no manual handling of excreta will take place, their dignity will be upheld.
During the first stage, Entrepreneur I sets up the ferro-cement toilet and septic tank unit and constructs 1,200 toilets and septic tanks in the first year. The investment required to set this up is around 3.5 lakh which can be availed of as an SME loan.
Total cost of construction of 1,200 toilets is Rs 2.4 crore which can be accessed from available government funds, donors and the community. For this, the entrepreneur needs to generate demand through raising awareness and strategic marketing and leveraging government funding.
This entrepreneur will also build in profit for himself/herself in this cost. This implies that with an investment of Rs 3.5 lakh, entrepreneur I will have generated business worth around Rs 2.4 crore if he succeeds in building 1,200 toilets. The government also provides for up to Rs 20 lakh for solid and liquid waste management, which can be availed of.
Entrepreneur II buys a 5 ton truck and uses it to transport toilets and septic tanks and also fixes these. Total investment required to start and maintain an FSM business is Rs 10 lakh, which can be sourced as loans from banks.
After a year, Entrepreneur II transforms his truck chassis to a tanker mounted sludge tanker (3,500 litre capacity) and water tank (1,000 litre capacity) starts FSM services after a year with the use of sludge pump, water pump, air compressor.
Financial modeling indicates that it is possible for entrepreneur II to have a payback period of 30 months with a salary of Rs 16,000 per month and subsequent earnings of Rs 46, 000 per month.
A multi-party agreement between the state govt, NGO, entrepreneur and the user can be executed to prevent leakage and ensure commitment to sanitation and hygiene and the economic model.
The model is based on certain assumptions:
Business includes FSM and provision of ferro-cement toilets (base only, not superstructure) and septic tanks
1,200 households will be provided with a toilet and septic tank. This septic tank is cleaned once in a year
Septic tanks of around 1,000 litre capacity
Cost of toilet + septic tank = Rs 20,000. This includes cost of construction, cartage and profit.
Four septic tanks are cleaned daily.Tanks are cleaned once a year. Rate of cleaning = Rs 1,200. Radius of operation in rural areas= 25 km
Number of users per toilet = 8. Initially one toilet can be shared between two families or two HH, which means that 2,400 families will be served. This also means that the maintenance cost drops 50 per cent, to Rs 50 per HH.
Linking bathrooms
Where bathrooms exist, the wastewater generated can be connected to the septic tank. Here arrangements need to be made to dispose the supernatant. These tanks can be cleaned once in three years.
In small towns, which are not connected to the sewerage system, in absence of regular cleaning, these septic tanks can become a nuisance. Solidification will take place over time, reducing the capacity of the tanks. Thus, till such time the septic tanks are connected to the sewerage system, these tanks need to be cleaned once a year.
Final septic water and sludge disposal
The final wastewater generated can be diverted into a reed bed aerobic cleaning system. At present wastewater from septic tanks from the HHs is not linked to sewerage system and as a result, is allowed to spill over- not a healthy practice. This needs to be disposed in a scientific manner.
Till such time, septic tanks are connected to a sewerage system these tanks need to be cleaned annually, if not sooner, instead of once in 3 years or before these start overflowing. If there is a piped water supply and flushing system, septic tanks will start overflowing with wastewater sooner rather than later.
If there is no proper wastewater disposal system, it requires pumping and cleaning more frequently, which means additional business for the FSM service provider!
The sludge can be disposed of by composting with other appropriate waste material and used for agricultural and horticultural purposes.
Testing of model
The above model needs to be replicated in at least four different regions to understand the dynamics and challenges involved during implementation, so that corrections can be made for widespread replication. But it is a model that offers a total solution and options for livelihood development.
Septic tanks: A neglected option
Septic tanks are the first step in the process of sewage conditioning, in a subsurface disposal system. The importance and function of the septic tanks is commonly disregarded, yet science and experience proves its importance.
Septic tanks collect and treat wastewater; separate sewage into three different zones: sludge, scum (floaters) and clear zone in the middle. It allows for anaerobic digestion of organic matter. While anaerobic digestion does not remove disease-causing organisms, it reduces the biological oxygen demand, total suspended solids, fats, oils and greases. The removal of disease causing microorganisms occurs in the subsequent steps when the supernatant is disposed in an aerobic drain field system.
As a final stage of disposal, the treated effluent from the septic tank is discharged to the leach field where it percolates through suitable ‘septic zones’ and finally into the subsoil for further purification.
The functioning of septic tank is correlated to the design, usage, its correct size for occupancy and long term storage of the sludge. Settling of solids and flotation of scum requires a calm glow to promote growth of bacteria. A proposer design and functionality is critical in improving the effluent quality leaving the tank.
Ashok Khurana is a retired Director General, Central Public Works Department, Govt of India
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