Have been using a vermicomposting toilet for little better than 4 years now, currently in it's third incarnation. The original collection box I built after reading Anna Edey's book and quickly discovered that I had not built a waterproof collection vessel. A fair amount of effluent went out the pipe as desired, but it also leaked from every seam below water level. After several months I dug the box out, lined it with plastic, and refilled. This still leaked a little, but not nearly as badly. However, by last summer the box itself was showing signs of rotting, so I decided it was time for another revision. This Fall I used an IBC (275 gallon plastic container), lined the bottom with gravel and filled it with sawdust (what I had readily available). This worked well for a few weeks, then all the worms downed. My collection tank has never overflowed, but the water doesn't drain nearly as quickly as it needs to. As with many other projections, the learning continues. Some lessons thus far:
1) the plastic container with thread outlet and valve was a huge improvement over building a box and trying to make it waterproof, then figure out how to connect pipe to it.
2) as noted earlier on this thread by Wendy (wish I had read this a few months ago) sawdust is too fine. It will saturate, then drain far too slowly and drown your worms, leaving you with a stinky mess.
3) In my first and second attempts I used much coarser material (leaves, waste straw, wood chips) and results were much closer to what was described in Anna Edey's book.
4) This system is much more user friendly than either the self contained composting toilet we tried initially, and the bucket system we used between the 2nd and 3rd attempts. We have frequent visitors and Woofers from all backgrounds, and some people are very uncomfortable with toilet alternatives. I am fairly ambivalent to adults that express distress over a bucket of sawdust in a nicely built box with a lid and traditional seat, but I really did feel bad for my friend's 4 year old daughter that was in tears over it not being a "proper" toilet. The vermicomposting system avoids these issues, and unless it comes up, most people don't realize we don't have a standard septic system.
5) As the person responsible for cleaning and emptying the self contained composter and bucket system I am also a big fan of this system. The bucket system was much easier to deal with, but was still one more chore to add to a list that is already long enough.
We get occasional temperatures in -5 F range in winter and so far the worms have gotten through just fine. Originally I was concerned about what to plant in the filter beds, but they pretty quickly vegetated themselves with thinks that didn't mind cold temperatures. Natures hates to see nutrients wasted.
