Improving the Bug-Out Location By Handling Gray Water

Having all waste water whisked effortlessly away is one of the great under-rated luxuries of modern life.  That luxury might not be there in an emergency, and/or at the bug-out location (BOL). What’s the next best thing?  Handling gray water efficiently is part of the answer.

Water comes in roughly four grades:  Potable water is safe to drink.  Clean water is from streams or similar sources, easily treated to be made drinkable. Black water is overtly contaminated with human waste (contains urine and/or feces) and is a health hazard.

What is gray water?

Gray water is somewhere between clean and black.  It’s mostly water that has been used for washing.  Water from sinks, washing machines, and showers is gray water.  It’s not something you’d want to drink even after running it through a good filter, but it’s ok to discard without further treatment.  It’s not going to make people sick if it gets into the ground or surface water.

Gray water from showers and sinks can be safely ditched or used for watering.

With modern sewer systems, we just run black and gray water through the same water treatments.  It’s wasteful, but easy, and we can afford it.  If that convenience goes away due to infrastructure collapse or was never present (such as at a BOL), it’s much more efficient to separate gray and black waters and treat them differently.  Other posts, either present now or to appear very soon here at 3BY, deal with the black water (search toilet).  Today’s mission is to talk about gray water handling. Salty and I talk about it in this podcast:

I spent the last few days visiting a friend so far rural that she doesn’t have government-supplied water or sewer.  She has a gray water system.  Some of what’s here I learned from her design; other parts I learned from what she wished she’d done differently.

Making it simple

If you have to build a system anyway, both building and servicing it will be easiest if the lines are short. One way to do this is to make all the gray water sources physically close to each other.  We don’t usually put the showers next to the kitchen, but there’s no reason not to if there’s a nice wall between them.

On a related note, it’s nicest if all the gray water sources are pretty close to the side of the building where you want the gray water to exit.  Visualize the other alternative:  If you put the sink on the north wall and run the line out through the south wall, what happens if a firm clog happens right in the middle of the cabin?  You might have to tear up the whole danged floor. Also, it raises the risk that any clog would be out of reach of a snake from one end or the other and so require digging up the line.

Making it easy to service

If you’re in a time or place with no sewer service, odds are good you don’t have a well-stocked plumber to hand.  That means your gray water design should be easily user serviceable. Short lines are a good start.  So is having lots of clean-outs.  A clean out is a joint in the pipes that can be disassembled to allow a snake or other tool in there to clean out clogs. Snakes can be purchased at hardware stores and might be a worthwhile prep.

Drain snakes such as this one are quite cheap, easily stored, and invaluable when you can’t just call a plumber for your gray water drains.

Escorting the gray water outside

You can either just let the gray water run away downhill, or collect it in a drum or some such to use later.  One could even run it into a drip irrigation system, such as the one described here (clicky).

A key word there was ‘downhill’.  You’ll want to make sure there’s a significant drop between the lines in the cabin and the release or collection point to discourage sluggish water movement in the pipes.  The more time water spends sitting in the pipes, the more gunk is likely to settle out and cause clogs.  Also, if you’re releasing into a ditch, standing water will encourage mosquito breeding.  Who wants to set up a mosquito hotel right outside the cabin?

This mosquito might have been born just outside the cabin in a badly designed gray water drain.

If you live in a cold climate, consider how deeply a pipe has to be buried to not freeze … then put yours a little deeper than that to accommodate the eventual extreme weather events.  I love frozen waterfalls, but one that block my gray water pipes? Not so much.

I’d also want a critter cap on the outside end of the pipe if releasing the gray water into a ditch.  I wouldn’t want to invite every animal smaller than the pipe diameter up into my cabin through the kitchen. My friend was wondering how all those mice were getting in…  A screen cap with retaining band ought to do the trick.

Be eco friendly – this is Your ecology after all

One thing to keep in mind with gray water is that every chemical in that water is going into your local environment.  I’m reminded of a book I read as a kid where a tree became sentient.  It ended up killing the housekeeper.  It was self-defense, really:  The house had a gray water system and the housekeeper kept using Drano which was killing the tree’s roots.

There are plenty of quality biodegradable cleaning products, so it’s not hard to choose them instead of very acidic, very basic, or very toxic choices.  In a similar vein, enzyme-based drain cleaners are going to be more suitable than the strong acids.  It’s just something to keep in mind.