Temporary composting urinals for an event

Hi folks,

I have a large event coming up and while I have hired temporary toilets, I think I need to supplement with some extra urinals - potentially 300 people consuming a LOT of beer My main objective is to keep it simple and cheap, and I have plenty of wood chips available, and some old mouldy hay bales. My vague plan is to setup a long narrow trough full of chips, with hay bales as a wall. It can compost in place for a few months, before being spread in the garden.

Anyone tried something like this? Any issues to be aware of, beyond what normal compost-heap peeing would indicate?

Could we have potentially too much volume, leading to liquid seeping?

Have you ever seen the straw bale urinal?  Check out this thread:

https://permies.com/t/58193/Straw-Bale-Urinal-Men

https://www.rootsimple.com/2013/04/a-straw-bale-urinal/

The technology here is so simple, but so smart.  If you purchased just two of these things, you could install them in either a large round bale, or in a stack of 3 or 4 normal sized bales.  Instant pee station!  And the great thing is that all that pee would be collected in the straw for your future use as a nitrogen rich mulch.  

Sadly it looks like those strawbale devices are not being made. I looked at them previously and thought they were great, but I can't find anything about them more recent than 2014  More to the point, I'd rather use what I have and not have to fork out a chunk of money for what will amount to a single use plastic product.

I think I will just have to build it and see how it goes.

My main concern is that we might end up over loading it with too much volume in the space of a few hours. I'm currently thinking that a test might be in order.

300 people at the event - 150 men, most of whom will want to pee at some point. Let's say that they all go heavy on the beer and need to deposit a litre each - so 150 liters spread over 3 hours. We have plastic buckets that are about 20 litres.

So for my test I could pour in 10 buckets of water, over the space of 20 minutes or so, and see what leakage, if any, we get.  Sound reasonable?

Wow that is one hell of an opportunity for biochar inoculation!
"Just pee on that black pile"

Good point - I can certainly fill it up with a lot of biochar too!

Michael Cox wrote:

My main concern is that we might end up over loading it with too much volume in the space of a few hours.

You'd be amazed with the water-holding capacity of a couple of bales.  And if you were to create a wood-chip filled space between the bales, as you mentioned in your OP, it would be more than adequate to absorb the pee of 150 semi-drunk revelers.   Would they be able to shoot straight?  That would be my question.

Lets say you put two bales cut-side-up next to one another, with a 6 inch gap between them filled with wood chips.  That's about 12 square feet of surface area, and it would be close to 2 feet deep.  If the majority of the pee is "deposited" on the wood chips, and then either soaks into the chips or straw/hay, what little actually soaks through to the ground would be minimal.  I'll bet that such a set-up would absorb EASILY 75 gallons or more before it would trickle down to the ground.  And if it does, its not like it would be running out from under the bales.

If you wanted to be absolutely certain that you wouldn't get any run off, dig a 8 inch deep trench between the bales, build your hay-bale structure around it, then fill the void between the bales (and the empty trench below) with chips.  That would give you 50 more gallons of capacity.  

An average hay/straw bale is about 4' long.  So two bales, side by side, would be 8' long.  That's enough for 3 guys to stand next to one another and take a leek.  Two bales on either side of the trench -- 4 total.  If you wanted to put sides on it, that would be two more bales.  Now we are up to 6.  If you wanted a back on your "urinal", then add two or four more bales.  Add two more side bales as well to get it up to height.  Now we are at 12 bales total  And a couple generous scoops of wood chips.  Bada bing, I'm a frickin' engineering genius.  

I'd put a target for them to shoot at on the back wall of the pisser.   I can think of several politicians and Hollywood celebs whose pictures would make a convenient target.