My portable compost toilet at home is a pair of five gallon buckets stacked one on top of another, by the washing machine. One bucket is normally full of dirt from my garden; the other one, the toilet, starts as a bucket one-fourth filled with dirt. When using my compost toilet, I get the two buckets out and put them beside the WC. I sit on the toilet bucket and get the job done; the solid waste lands on the dirt. Once my bowl is empty, I move to the regular WC and clean myself. The next step is to use a little shovel in the 'dirt bucket' to pour dirt on top of the fresh solid waste. I use copious amount of dirt to cover the whole thing so that there is no risk of any odor coming out of my toilet bucket. Once done, lids are put back on the two buckets and the buckets go back to their place by the washing machine. After a three or four time use of the compost toilet, I take the 'toilet bucket' out in the yard and empty it out in a pit. The bucket gets thoroughly washed and restocked with fresh dirt to start the process again.
I also have a solution for my kidney waste. I collect my kidney drain in an empty milk gallon. Once full, this container, full of high quality nitrates, is emptied out in the garden.
What do I achieve by doing this exercise? I get the confidence that I can be off grid without using a septic system. I generate high quality fertilizer for my garden. I save water. [I only need to flush the WC once every week or so because I use the WC only for cleaning myself, using water.] I feel good being a responsible Earth citizen.
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Use of compost toilet while traveling on the Pakistani motorways
Yes, there are a few OK toilets along motorways in Pakistan, but nothing beats having your personal toilet with you, that only you use.
If you have not traveled with a portable compost toilet/bucket toilet before I will encourage you to first use the bucket toilet in the comfort of your home. Some people fear they will not be able to balance themselves on a bucket, or that the rim of the bucket will feel painful. I never had an issue with the balance, nor did I ever find sitting on the bucket painful. You must try out the bucket toilet at home before taking it with you on a road trip. And you must feel comfortable that once the waste is well-covered with dirt, a 4+ inch thick layer, there is no odor from the compost toilet--cats already know this--and if you will have to show your compost toilet to a person not knowledgeable about its contents, they won't be able to guess what is hiding under the dirt.
You have a choice of two different types of compost toilets to use in your road trip. The simplest one comprises only one bucket with its bottom cut out. The bucket is your toilet and your waste will land directly on the ground. Once done you can use a shovel to cover up the waste; wash your bottomless bucket and you are ready to go.
If you want things to be more contained consider taking your compost toilet with you. When packing the compost toilet for the road, you will have to use the 'toilet bucket' for both relieving yourself i.e., emptying out your bowl, emptying out your kidney, AND for cleaning yourself. This can generate a big quantity of liquid, but a thick layer of dirt can easily cover all that.
For making your portable toilet private, you can consider carrying four one-half inch rebars, four 4.5 ft. long ¾ inch PVC pipes, and a 4.5 ft. wide, 18 ft long fabric. You can park your car slightly away from the road. Hammer four rebars in a square fashion, four feet apart; put PVC pipes on top of the rebars and wrap the fabric around the PVC posts. Your very private, exceptionally clean compost toilet is ready for your use!
Road side stop to use compost toilet