Intro: Simple Grey Water Gardening Hack
An easy to implement grey water garden setup.
A rubber water reclaimer funnel (optional, but recommended)
Several lengths of hose
A large deep bucket (I used a kitchen garbage bin)
An immersion pump, with a float switch
A large storage vessel
A table (or similar support)
Step 1: Get the Water Out
This can be more difficult than it sounds, depending on how your bathroom plumbing is set up on the outside. I have a small PVC elbow joint with a cap, that is essentially concreted in. Nothing moving at all. I first experimented with just shoving a length of hose into the PVC pipe, which worked but wasn't very efficient. Amazingly, I found a rubber funnel at the hardware store just like I'd imagined I'd need (although I'd never heard of or seen one before). You just scrunch the funnel up and shove it into the hole in the PVC elbow joint (a flat screwdriver helps) until its in the horizontal top part of the pipe, then attach a hose to the end. Perfect.
Step 2: Grab a Shovel
My downpipe is very low to the ground, so I had to go underground to keep things flowing. I dug a hole that's ... well it's about the height of a kitchen garbage bin. I put a couple of bricks in the bottom to prevent things getting too bogged down in there too quickly.
Step 3: Drop in a Pump
This is the most expensive step. I picked up a rather neat little immersion pump from the hardware store for under $50 Australian, which I thought was very good value. Your mileage may vary. Make sure that it has a float switch. Because I've used a bucket that is smaller than the recommended size vessel to use the pump in, I used some cable ties to restrict the movement of the float switch. It still moves up and down, but now it only has to move a little way to tilt enough to throw the switch. Otherwise I'd have to have dug a hole big enough for a wheelie bin, and I just wasn't up for that.
The judicious placement of an ashtray into the bottom of the bucket (something that happened to be the right size and doesn't float) stops the pump from jumping around when it turns on. If it moves about in the bucket then it can jam the float against the wall, causing either your pump to run itself dry or your system to turn your garden into swampland.
Step 4: Attach a Short Hose
This hose goes to the elevated storage vessel. In our case an old bathtub serves in place of a tank. A large capacity tank might be marginally better, but I think you'll agree that an old tub wins hands down on the value-for-money scale.
I bought a coupling for the 13mm polypipe from the hardware store where I got the pump. I had to hit the outlet elbow pipe from the pump with a hacksaw in order to get the coupling to fit. Not sure if that's what the manufacturer intended, but it seemed to be the only way this was going to fly.
I also resurrected an old table that was falling apart down near the back fence, and braced it in the hope of preventing it from crashing to the ground. All good so far.
I lashed the hose to the table with a small piece of wire, just to hold it in place.
Step 5: PVC Downpipe
The PVC downpipe that was found doing very little on the side of our Brunswick rental is probably an optional extra, but I liked the repurposing of the extra clothes rack as a support, so I kept it. The ends are attached to the tub and the polypipe by what are known in the trade as rubber-glove-and-sticky-tape couplings, which seem to serve the purpose admirably well.
Step 6: Polypipe
This is definitely the most fun part.
I ran 20m of 13mm polypipe around my garden plot. One end is rubber-glove-and-sticky-tape coupled to the system and the other has a plastic bung in the end, which I picked up from the store for about 50c.
Once I'd had a shower and had a nice full tub of reclaimed H2O feeding into the poly pipe (after quite a bit of testing and fiddling around to get it working reliably) I fashioned a tool from a sewing needle and a removable drill chuck for the purpose of creating sprinkler holes in the polypipe. This was deceptively good fun, as I discovered that I could spike the polypipe with the needle to create a mini fountain at whichever point, and in whichever direction and trajectory I liked. There was enough pressure from the water in the tub to shoot the water 30cm from the hose, if I got the angle right. So I spent a most enjoyable half an hour tiptoeing around bringing aqueous joy to every little patch of my garden, and revelling in the idea that I will be watering it every morning when I take a shower, with no worries about water restrictions.