Pour the Liquids  

Use the Two Bucket Flush System: Some like to say “If its yellow, let it mellow; if it’s brown, flush it down.” This has been popular for decades, and there is nothing wrong with it. It does tend to mean the toilet needs to be thoroughly cleaned very frequently if you have a nose. Some extreme conservationists even just pee outside, regardless of the weather. There are many possibilities. 

I personally have a different system because it passes the Nose Test while not having to go outside when it’s snowing. In our shower, we have two buckets- one small, the size of a kid’s sand bucket. The small bucket we use for our liquid wastes. Then this small bucket is emptied carefully down the drain, avoiding the messy splattering that would otherwise occur if someone were to relieve themselves directly into the drain. Then the empty small bucket is filled by dipping into the 5 gallon shower water bucket, and poured down the drain. This gets rid of possible smells in both the small bucket and the drain, while USING NO FRESH DRINKING WATER!  The ladies’ toilet paper goes into the compost. Yes, of course, this is not the American way! The standard way is to take water from limited resources far away, pump it to a place to purify it to drinking water standards, then pump it to your house. Which is more sustainable? 
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The Two Bucket Flush System