Urine and wood shavings experiment

While cleaning out the garage I came up with an odd plan and I'd like to hear anyones thoughts or experiences on the matter. I have a big bag of wood shavings from madrone wood that was turned into bowls, I filled up a 10 gallon bucked with it and have been peeing in it as often as I can. It's been going now for about 2 weeks getting urine at least once a day. Will the wood compost? Will it get hot? too hot for the plastic bucket? Do I need to be concerned about off gassing in the sealed bucket? Any thoughts are appreciated.

I wonder if the right microbes are present.
Maybe a bit if manure or finished compost would help, but maybe thats not needed.
I look forward to your results.

dump that bucket in a sheltered spot so its in contact with the ground. nature will take its course and break it down. the salts will build up in the bucket and kill any bacteria present. outside the rain will leach the salt out of the urine. then the right bacteria and worms will move in and break the shavings down.

Bossie, ya done nailed it!

I definitely understand that it would work 'better' if i just kept peeing on my compost heap or on my straw bales, and I definitely have a number of other compost situations going on that are more sensible, this is nothing but an experiment. You are saying, mr. bossie, that the salt content of the urine will keep bacteria from developing and i'll just end up with urine soaked wood shavings, both nothing but older? That will be a dissapointment but I suppose I'll see. I'll be sure to update in the next few months, especially if something other than the above scenario happens.

Urine contains urea.  I think what happens is that naturally occurring bacteria release enzymes causing urea to breakdown into ammonia.  The properties of ammonia are that is highly soluble in water, but it is also a gas that may vent to the air somewhat, especially if warm or in high concentrations.  In high concentrations ammonia is anti-microbial, so if you want that (when sanitizing urine) don't dilute it, and if you don't want that (like for composting or fertilizing) then dilute it with a suitable amount of moisture and compostable matter.  I imagine it wouldn't be too difficult to pipe the ammonia gas into a cold water bottle and make "Windex" if that's of use as a glass cleaner, etc.  Also ammonia stinks so storing old urine indoors is not for the faint of heart.  

Having done this for years - using a sawdust bucket as a urinal - I can say with confidence that concerns about salt build up are unjustified. Start with a few inches of sawdust in the bottom. Top up a handful at a time with sawdust as you use it, so that all urine damp sawdust is covered with fresh. This supresses all smells.  As the bucket fills up you can empty it into a normal compost heap. It will get hot within a few days and be dark, rich soil in a few weeks. We haven't been using this recently, but when we do we love the benefits it brings to the compost.

This is covered in "The Humanure Handbook".

A few observations from our use:
Sawdust - especially from slightly green wood - works, better than shavings. They are more absorbent. Pine shavings, such as those used for animal bedding tend to be almost waterproof, and they don't settle as densely in the bucket.
Empty the bucket when it is about 2/3rds full. It is lighter, easier etc...
You can put a few sheets of newspaper in the bottom. The bucket will be a bit easier to clean.
If you get a smell you are doing something wrong. Add more sawdust.

Michael Cox wrote:Having done this for years - using a sawdust bucket as a urinal - I can say with confidence that concerns about salt build up are unjustified. Start with a few inches of sawdust in the bottom. Top up a handful at a time with sawdust as you use it, so that all urine damp sawdust is covered with fresh. This supresses all smells.  As the bucket fills up you can empty it into a normal compost heap. It will get hot within a few days and be dark, rich soil in a few weeks. We haven't been using this recently, but when we do we love the benefits it brings to the compost.

This is covered in "The Humanure Handbook".

A few observations from our use:
Sawdust - especially from slightly green wood - works, better than shavings. They are more absorbent. Pine shavings, such as those used for animal bedding tend to be almost waterproof, and they don't settle as densely in the bucket.
Empty the bucket when it is about 2/3rds full. It is lighter, easier etc...
You can put a few sheets of newspaper in the bottom. The bucket will be a bit easier to clean.
If you get a smell you are doing something wrong. Add more sawdust.

thats because the salts and ammonia is getting leached out in the compost pile. if just left in the bucket to compost, the salt will just sit in there basically pickiling your sawdust . once its added to the compost pile it gets diluted and leached which allows the right bacteria and worms to go and do there jobs. some salt can be tolerated but that much just sitting in a pail won't do much but stink to high heaven!

Ah, I see your point. My response is a dubious "maybe".

For a start the bucket cannot be used indefinitely. At some point it will fill up. It seems sensible to empty it into compost so you can reuse the bucket. That was how I interpreted the original post at least.

Regarding salts leeching into a compost heap, I think you may be overstating this. We added weekly buckets to compost heaps year round for a number of years. Regardless of the conditions, wet or dry, the compost would ferociously hot within days. Your proposal is that it is necessary for salts to leech out presumably by rain water before composting takes place, but direct observations in prolonged dryspells indicates that this is not required.

I think some more relevant conditions are
1) Buckets don't breath. Plastic sides prevent the slow circulation of air through a compost heap.
2) Large compost heaps come with warmth and a depth of insulating material

We always took care to fork aside the top layer of material - usually straw or grass clippings - and put the urine/sawdust charge into the middle of the heap. The pre-existing warmth really kick starts the decomposition process. Small buckets on the other hand simply don't have enough mass to hot compost without additional help.

I saw the title of this thread and immediately thought of this guy lol
https://www.youtube.com/watch?v=8wW5KR1pDxs

Nick, that's cute but we're not making gunpowder here.

Steve, I agree the salts and ammonia is getting leached out by water-runoff.  As you said, just left in the bucket the salt will just accumulate.  To clarify though, salt itself doesn't stink.  What stinks is 1) urea decomposing to ammonia, and 2) anaerobic decompostion/composting.  

Michael, assuming a good sized compost pile, I think if there's enough water for composting then there's enough water to dilute the salts.  If there isn't enough water for composting then take your pick as to whether you want to blame the dryness or salinity.

For a collecting container, I think a capped bottle or jug might be best because it is easier to handle and can be filled and capped and/or emptied often to minimize odors.

I totally agree with your 'relevant conditions' for compost to be warm and aerated, but I'm skeptical that new material has to be added to the middle of the heap.  Yes warmth "kick-starts" it, but digging into the center might just remove heat from other material in the pile, so while I could be wrong, I'm skeptical that there's any overall improvement on the pile, or at least enough to justify the extra effort.  

I agree small buckets aren't big enough to get hot on their own without additional help.

Sawdust on top might just help physically contain odors.  It's not exactly clear why absorbing moisture (like the bentonite clay or silica gel in a cat litter box)  reduces urine odors.  I think it just makes it so there's less contact between the urine and the air.  It might inhibit the bacteria that convert urea to ammonia.  Or it may help keep the ammonia dissolved in solution in the original water rather than off-gassing or having the water dry out in the air and thus off-gassing the ammonia along with it.  

Thanks for the experience Michael. I definitely wish that I had dust instead of shavings but it is what it is. A big hope here is that it will win my lady over to the acceptability of an indoor pee bucket (it currently lives on the back porch per her request) but I am also curious to see what happens. It is a 10 gallon bucket so it will take a bit of time before it is full, do you think that will affect it's performance? or will it just get started composting and maybe stall out at some point?

I can definitely see where the combination of urine and low density carbon debris (wood chips, shavings, sawdust, heck... probably even shredded junk mail) would create a premix for composting.  Strikes me it might even make a good means of turning up your heaps when they start cooling off before they're finished.  

As far as being autonomous compost buckets, I'm thinking that if you pee in a bucket of wood shavings and it works, you might want to see your physician.  Urine is, under normal circumstances, sterile.  There should be no microorganisms present in urine as the stream exits the body (abysmal personal hygiene notwithstanding.) I'm thinking that the overall mixture won't have enough simple carbohydrates to allow culturing of wild yeasts like is done with sourdough bread, rum, and some cheeses.  

I did exactly what you describe and told about it in this post:
Leaf and urine bucket failure
https://permies.com/t/22734

It seemed great for the first few weeks, but then went anaerobic in the bottom of the bucket, and started to fill the area with a powerful methane smell. In the post I described the time I tried it with dry leaves, but I had tried it a previous winter with sawdust and some kitchen waste and coffee grounds, with similar bad results.

Well I have a not very surprising update and I suppose final note on the experiment. After almost 2 months I fully filled the bucket with urine, above the level of the wood shavings. It didn't smell especially bad (i think because the bucket was actually fully air tight) and when I dumped it out onto the compost pile the bottom of the bucket looked about the same as the top. Basically just a pile of urine soaked wood shavings. Not the grossest thing on earth but not really a useful asset to keep around. Who knows, maybe the wood shavings will break down in the compost pile faster now that they're enriched with nitrogen. In any case, I've moved on to another experiment with the two buckets, bokashi composting. And the first bucket is almost full so I need the pee filled one to start filling this week. I will post a new thread with pictures of that and notes on how it handles a 3 person household that cooks a lot and produces a lot of compost.
Thanks as always for everyones thoughts and doubts.

Ok so ... If wood shavings are 500:1 and urine is 1:1 carbon: nitrogen, and one is looking for a 25:1 ratio for good composting, then *hypothetically*, if it were possible to make compost with just these two ingredients, then for a cubic yard of wood shavings, one would need 20 cubic yards of urine (4000 gallons) to get the right balance.
Is my math correct? (Just a thought experiment lol I'm not actually doing this) thanks

Hi Wenzday,

Welcome to Permies!  I am pretty sure you can post anywhere you can get into.  The Prime Directive here is to  Be Nice.

s. lowe wrote:While cleaning out the garage I came up with an odd plan and I'd like to hear anyones thoughts or experiences on the matter. I have a big bag of wood shavings from madrone wood that was turned into bowls, I filled up a 10 gallon bucked with it and have been peeing in it as often as I can. It's been going now for about 2 weeks getting urine at least once a day. Will the wood compost? Will it get hot? too hot for the plastic bucket? Do I need to be concerned about off gassing in the sealed bucket? Any thoughts are appreciated.

I can't believe I am just now seeing this topic. I have a great deal of experience with this! I have a source of untreated poplar wood shavings from a wood shop. I pack a 5 gallon bucket tight with these for urination purposes.

After the first day or so, I will dump a glass of aquarium water in the bucket to jump-start the composting. Another GREAT alternative is to periodically dose the bucket with SPICE compost innoculant.

Anyhow, the bucket will smell, but the microbes from the aquarium, or the SPICE compost mix do a great job and keeping this to a minimum.

I have found that once the shavings are saturated, it is nearly the perfect ratio for composting; however the run off is a little hot.

I like to mulch nitrogen-starved plants with the saturated shavings. I will dump the soggier stuff in a fallow bed to help prep it for next year.

Alternatively you can leave it in the bucket, sealed, outside, for about about a year; and let nature break it down so you don't have to worry about the run off.

What I think is really interesting about the bucket method is that it should retain the most nitrogen from the piss as possible. The point of the experiment should not be to compost the wood, so much as maximize the nitrogen.

Mike Phillipps wrote:
Steve, I agree the salts and ammonia is getting leached out by water-runoff.  As you said, just left in the bucket the salt will just accumulate.  To clarify though, salt itself doesn't stink.  What stinks is 1) urea decomposing to ammonia, and 2) anaerobic decompostion/composting.  

I totally agree with your 'relevant conditions' for compost to be warm and aerated, but I'm skeptical that new material has to be added to the middle of the heap.  Yes warmth "kick-starts" it, but digging into the center might just remove heat from other material in the pile, so while I could be wrong, I'm skeptical that there's any overall improvement on the pile, or at least enough to justify the extra effort.  

I agree small buckets aren't big enough to get hot on their own without additional help.  

We humans tend to have too much salt in our diet, that is why when hiking your supposed to pee on a stump or rock or other durable surface so the wildlife trying to use it as a salt lick don't destroy some innocent plants. So if your bucket is under a roof I can see salt building up to preservation levels.
Putting it in the middle of your heap I see as having the benefits of surrounding the new material and aerating the stuff replied on top.

Aurora House wrote:

Mike Phillipps wrote:
Steve, I agree the salts and ammonia is getting leached out by water-runoff.  As you said, just left in the bucket the salt will just accumulate.  To clarify though, salt itself doesn't stink.  What stinks is 1) urea decomposing to ammonia, and 2) anaerobic decompostion/composting.  

I totally agree with your 'relevant conditions' for compost to be warm and aerated, but I'm skeptical that new material has to be added to the middle of the heap.  Yes warmth "kick-starts" it, but digging into the center might just remove heat from other material in the pile, so while I could be wrong, I'm skeptical that there's any overall improvement on the pile, or at least enough to justify the extra effort.  

I agree small buckets aren't big enough to get hot on their own without additional help.  

We humans tend to have too much salt in our diet, that is why when hiking your supposed to pee on a stump or rock or other durable surface so the wildlife trying to use it as a salt lick don't destroy some innocent plants. So if your bucket is under a roof I can see salt building up to preservation levels.
Putting it in the middle of your heap I see as having the benefits of surrounding the new material and aerating the stuff replied on top.

like i said at the beginning of this thread, as long as youre dumping it on a carbon source outside nature will do the rest. ive stopped using the bucket/ chips inside. instead i pee in old milk jugs and store under the sink. when full i dump them on a arborist pile of woodchips in the back yard. in winter i store the full jugs in the garage until spring then dump them out on the pile. just make sure you have a good amount of chips. a yard is good 2 yards , better.

You can definitely compost sawdust,  wood shavings,  shredded bark, alfalfa bales, oat/wheat/barley bales etc with just urine. My main suggestion would be to make sure that is wet enough.  Wood is very very absorbent. Which is why it is used as animal bedding.  The second concern is if it can get enough air being in a plastic bucket.  My daughter's father-in-law put cardboard down in one corner of his garage for composting I might suggest that to you opposed to the plastic bucket. You can even put biochar across the bottom. Yes of course throwing a cup or 2 of native soil or manure is helpful but not absolutely necessary if you don't have it. You can also leave the bale whole and throw urine on it. Some people let they're urine "cure" for 3 weeks or so.. they say because of pathogens and other reasons.  I don't.  After all you're composting it anyway. I will say not to use urine from someone on prescriptions or antibiotics.   I do always let my bales sit for awhile anyway to help further kill any weed seeds.

Composted or partially broken down sawdust and shavings are wonderful for planting potatoes in.

s. lowe wrote:While cleaning out the garage I came up with an odd plan and I'd like to hear anyones thoughts or experiences on the matter. I have a big bag of wood shavings from madrone wood that was turned into bowls, I filled up a 10 gallon bucked with it and have been peeing in it as often as I can. It's been going now for about 2 weeks getting urine at least once a day. Will the wood compost? Will it get hot? too hot for the plastic bucket? Do I need to be concerned about off gassing in the sealed bucket? Any thoughts are appreciated.