Composting toilets offer an unique, water saving, low energy, low infrastructure method for treating our toilet wastes and recycling them to be used again for crop production.
Below we look at the many advantages that hey have over septic and sewage systems as well as looking at the disadvantages that can occur.
(Pros and cons – “for and against”, or “advantages and disadvantages”)
PROS
Individual System Pros
Water saving
In most cases complete toilet flushing water saving for households.
The household saving is between 10 – 40 % of average household use depending on location and situation
For households carrying out water harvesting and storing it means much less harvesting storage is needed.
(If you implement other household and garden waters saving techniques you can cut your household water use to 10 – 20% of average household use.)
Produce nutrient rich compost
You can use the resultant compost for orchard and woodlot trees.
Reduced pollution by effluent
In the case where septic tanks would have been installed, the composting toilet systems reduces or eliminates environmentally harming effluent.
Reduce underground pipe systems
Composting toilets eliminate the need for underground piping systems to remote septic tanks in the garden or remote sewage systems. However, there is still a need for a smaller, closer greywater system.
Remote toilet location
Allows toilets and amenities buildings to be located where it was not possible with water based system. Many amenities in remote wilderness areas are now composting toilets.
Low cost sanitation solution
Low cost composting toilet installations can be used in households where the community are unable to afford the high cost of a central sewage treatment system and the associated high costs of installing pipes and pumping stations.
Change personal attitudes to resources
After years of “Flush and forget” us of flush toilets, the use of composting toilets has shown to change the users attitude to resource overall towards an attitude more accepting of reduce, reuse or recycle.
Increase flexibility travel RVs and Marine use
Composting toilets have allowed longer periods between toilet waste removal in marine use and RV’s.
Household organic scraps can be added
You can put household scraps through many systems particularly if composting worms are part of the composting system.
General Society Pros
Reduce water savings for a community by up to 40%
Sewage and septic toilet systems use valuable (and costly to treat) drinkable water to flush.
Sanitation costs mimic population better and will cost less overall
A sewage system and pipework to every house is a large capital cos often with large loan and interest payments for many years. It also needs to be made before it is needed, so it has less than optimum capacity until it reaches peak capacity when another is needed, which is below capacity until it reaches peak capacity and so on
Individual household composting toilet installation mimic the need exactly, reducing greatly the capital cost required.
Reduce need for fertilisers
Fertiliser production is mostly from finite mineral reserves and carbon causing petrochemical processes.. By making mineral rich compost we do not have these costs for nutrient production and the end product (compost) is also in a form that is better for soil application.
Reduce nutrient pollution
Septic tank and sewage systems often increase downstream nutrient flows causing eutrophication and death of marine species and damage to marine ecosystems.
Sewage systems often have leaking joins causing underground pollution.Apart from compost, composting toilet systems produce a quantity of greywater, that is easy to treat and not usually a cause of nutrient pollution.
Asist in localised fruit and timber energy production
Compost produced can be dug into soil for assisting in orchard and timber crops production at a local level. This is energy efficient nutrient recycling.
Reduce damage by infrastructure
Digging extensive pipe systems to carry sewage causes damage to ground and intrusion into natural areas and areas where people live. Composting toilets eliminate most of these pipe installations. There will, however be a need for localised greywater treatment installations.
Change attitude to wastes
The use of composting toilets causes an attitude change to waste, encouraging an move towards acceptance of recycling and reuse of resources.
System problems are seen easily and can be corrected before environmental damage
A breakdown in a sewage treatment plant can spew out large quantities of untreated sewage causing major problems.
A breakdown in a composting toilet system is a small, localised event that can be treated easily and causing a small amount of problems.
Eliminates the mixing of valuable nutrients with toxic chemicals
The traditional sewage system mixes valuable nutrients and minerals with toxic household and industry waste which often is put down the sewers. The resultant sludge is not safe for use in agriculture.
Composting toilets eliminate this mixing and leave a valuable nutrient compost. It also reveals the toxic wastes from industry and encourages treatment.
CONS
Individual System Cons
Overuse of systems results in user problems
Problems caused by overuse in septic and sewage systems is transferred to the treatment facilities (septic tank and sewage treatment plant). The user does not see these problems.
In the case of composting toilets, the overuse causes local problem (tank fills up!).
This could be a problem for users not familiar with maintaining the systems.
More individual maintenance
Composting toilet systems are not “flush and forget”. They are a living system so users need to be aware of small changes to their behaviour to ensure best composting.
Can be higher individual cost os installation vs sewage
The large capital costs of sewage treatment plants and pipe systems are transferred to individuals. Manufactured composting toilet systems are usually more expensive than household costs for connection to a sewage plant, although are similar to septic tank installation costs.
Greywater systems now required
In a sewage or septic system the greywater (sink and shower waste water) is piped into the system with the toilet wastes
In a composting toilet system the blackwater is separated from the greywater and a small treatment system is needed for the greywater.
The nutrient loadings are greatly reduced, so the system needs are small.
General Society Cons
Attitude change by authorities
Need a change of attitude by authorities moving from a system of central treatment and maintenance to a system of support for composting toilet units and their maintenance.