Humanure and Pet Feces

Just hear me out!  I should start this off by saying that ANY time you are processing feces, you must be careful to keep it seperate from your vegetable garden until it is broken down sufficiently.  In addition, one must take care to account for the movement of groundwater.  So locating it next to an open body of water that is not sealed may not be a good idea either.  Also, processing feces directly up hill from or next to root crops like onions and carrots may not be the best idea.  If sufficient distance is provided, and it is being done on a small scale, then its been proven to work.  Septic tanks are common in residential areas so this method is not as outlandish as one would think.  If one wants a more sophisticated approach they could allways use a small scale leachfield like a Watson Wick.  This makes the nutrient more immediately available to plants than in a septic system where you may lose much of it.  One may want to fence it off to keep dogs and wildlife out:

There are more simple ways of handling feces.  As an example, in our yard we have a worm tower for dog waste.  Dogs are carnivores so this could be a good example.  Lets say you have a worm tower where the dog waste is processed.  Bacteria break down the dog feces and other material put into it, worms then eat those bacteria, then excrete feces of their own.  The worm manure is further processed by bacteria and taken up by the roots of a large maple tree.  When this tree sheds it's leaves, they are used to make compost or mulch.  The compost or mulch is then broken down by bacteria and made available to your garden plants.  So to recap the conversion goes something like this: Dog Waste - Bacteria - Worm Castings - Tree Material - Bacteria/Fungi - Compost - Veggies.  How many times does humanure (human feces) have to be processed before its safe for the garden?  Thats the Golden question!  But I think its quite clear that a system like this would be safe.  It just needs to go through enough processing that all pathogens and parasites have been removed.  This method is basically a small scale version of an outhouse, but without the house.  Everyone knows you don't place an outhouse anywhere near a body of water, a well, or a vegetable garden.  http://www.ecofilms.com.au/ has a great diagram of how a worm tower works.  Directly in the vegetable garden, only kitchen waste and other non-fecal components should be used.  Bear in mind that in a setting where feces are being consumed by the worms, this should be located as far away from leaf crops and root crops as possible: 

There are things called composting toilets which people can use to render feces safe for use.  http://www.ceres.org.au/cerescontent/watertrail/files/compost.html has an interesting system design for using worms to process human feces:

This method could work and keeps fecal leachate from entering the surrounding soil.  The leachate is then handled seperately by a wetland type water cleansing system.  Aritifical wetlands are becoming more popular in treating sewage on a larger scale. Of course, I would not recommend using the results directly on your garden beds.  It should be further processed by nature before the resulting material ever ends up on your garden bed.

There are also ways of dry composting feces.  Many of the composting toilets you have seen or heard about involve the use of sawdust.  One goes to the toilet and when they are done a couple handfulls of sawdust or pulverized leaves ect..  are thrown in as a brown to keep things dry.  When the container is full it is changed and brought to an area where it goes through a long term process which can take many months.  This would involve no interaction with the groundwater either.  On a small scale many people may not have the room or resources for this type of operation.  But a little creativity could produce a system that works for you.  The resulting compost can be used on fruit trees or plants that produce mulch to be used elsewhere.  It would not be advisable to ever use this type of compost directly in the garden although there are people that do it.

As you can see, there are perfectly safe ways of using feces to grow veggies, and I don't mean manure, I mean FECES.  One just needs to be aware of the proximity to vegetables, groundwater, and pests.  Complex processing systems that involve regular human intervention are going to attract pests so one must be aware of and make attempts to mitigate that.  Passive systems are sometimes the best on a small scale.  One has to remember that the area where the feces are processed must be a good distance away form the garden.  Perhaps an area where fruit trees or other perennials are located would be best since any nutrients that leach out of the are would be able to for use by the fruit trees.

While its not possible to create a truly closed loop system, this is a major step towards that outcome.  Many places do not allow this so proceed at your own risk.  But, think of all the nutrients leaving your property which can be turned right back into food again.  Not only is it wasteful, its stupid.  Lets try and push the boundary on these types of things and open a dialogue.  Lets change the paradigm.  We are part of nature and our manure belongs in the landscape as much as the next animal.