three years of composting toilets

Hi All,

We have been using a composting bucket toilet for 3 years and I want to relate some of our experiences as related to your "pooper" design project.

We do not divert urine as a general practice ... the composting process needs moisture.
In my opinion, sawdust is definitely the best cover material. We are fortunate to have many small sawmills in our area and sawdust is freely available.

Now just a few logistical observations. We use 5 gallon buckets which are changed when 3/4 full. Two of us using the toilet fill 2 buckets per week. The bucket weighs 20-25 lbs when full. Translating this to the 55 gallon system ... one person fills 5 gallons/week so 11 people will fill 55 gallon/week and the drum will weigh approximately 200 lbs. Also, if the plan is to store the drums for 2 years, you will need 104 drums to service 11 people. In addition, I think there will be a composting problem since no air will be reaching below the surface of the filled drum. With the 5 gallon bucket system, the buckets are emptied into our compost bins and then layered with straw. The straw allows air infiltration throughout the bin.

Just some things to think about.

Good luck on your projects.

Regards,
-Tom

Thanks for the info it is good to hear from someone using the same system I am interested in. Just a quick question, how much sawdust do you go through?

Bio char might be your answer to making use of that excess waste.....composting toilets are unusually small scale systems

Tom I would be interested in hear more about how your system works. Did you do anything to the 55 gallon barrel? How many 55 gallon barrels are you going though a year? How long do you leave it in the barrel?

I'm not Tom, but I can say that he is not using the big 55 gallon bins, and he is not working with the dry outhouse idea. He is using 5 gallon buckets and transferring to a composting system.

I don't think you can directly compare the two systems, because urine is liquid, and liquids weigh a lot. In a dry system, the urine is diverted elsewhere, and the bucket fills more slowly. Composting is not really the goal, at least not like a garden compost pile.

Hello Again,

Sorry I haven't responded to this post in timely manner, but this Summer has just gotten crazy-busy for a lot of reasons.

Julia is correct, we do not use 55 gallon barrels. The 5 gallon buckets are dumped into a 4'x4'x4' compost bin and covered with straw.

As far as the amount of sawdust, the 5 gallon toilet bucket might use 3 gallons of sawdust when it is almost full. It seems that the usage is about 1 bucket per person per week, so about 3 gallons of sawdust per person per week. My pickup loaded with sawdust lasts a long time, at least 6 months.

Hope this helps.

-Tom