We have the greywater done! The house is now entirely free of water-waste, at least in the form of water that only gets used once.
I designed a pumice wick system for our house, as that is the system that seems to best meet our site and our water-use needs. The bathwater and sink water flows down the drain, out of the house and into a trench in the yard, where it moves through pumice rocks that underlie the garden, and thereby waters the herb and flower gardens.
That’s the short form. It took three full days of work, and many human-hours, to make it happen in the real world. And there are still some details to finish, of course. But the system is in and functional, and plants are growing in it; that’s the important thing for now. When we get back from our Thanksgiving trip to Arizona, I’ll finish detailing the drain areas–and hopefully catch up on a dozen other small things that need catching.
So, first we dug trenches no less than 3′ from the foundation of the house (because you really don’t want to be channelling your water directly into the foundation of the house and all, and this system will also serve as a partial passive rainwater catchment system, too). Foxwoman, myself, Jenny and Alan all spent time digging, though Fox did the lion’s share of the ground-breaking pick work and primary trenching. Here’s the back of the house with the trench started:
and the front:
Both trenches come straight down the side of the house from where their drains respectively exit the walls, and then turn the corner to come around near the back door. They also both terminate in a “french drain,” a gravel-filled pit (okay, a pit that i will get around to filling with gravel in the next few weeks). This provides what is called a “drain to daylight”–an easy way to see if the system is working–and a place for excess water to escape to that channels it further away from the house, rather than allowing it to build up closer during peak use periods. Like if, for some reason, nine people took showers and there was more water in the trench than it could handle. Or, more likely, during monsoon season when the rainwater runoff is intense and powerful and immediate. :)
Having roughed in the trenches, we got ahold of a friend who is a professional plumber, Bugeye. He came down from Santa Fe to do the actual plumbing rerouting for us. We initially thought we could do that ourselves, but the more we read about it, the more we determined that professionals really do some things better, and those include greywater. It’s easy for an amatuer to do it wrong, by all accounts, and we decided not to risk bungling it and wasting lots of time and possibly money, but instead to hire someone to do it right the first time. He did. :) Very competent fellow.
So first, he explored the underside of the house and verified which pipes were going where, and what would need to be cut and diverted to accomplish this. Then, having determined exactly where the pipe would need to exit the house to get the most fall (so that gravity will push the water out and take it as far as it needs to go) we rented a tool from home depot and drilled a hole in the wall. Here’s Bugeye, doing that:
and the resulting hole.
While under there, Bugeye discovered exactly where the cockroaches were coming into the house (which, as we suspected, invovled the city sewer connection). Having drilled the 4″ hole in the wall, we brought over the shop vac, put an old sock on the intake end inside the bin, and put the hose through the hole, and Bugeye vaccuumed up all the bugs he could find for us. These were then caught at the other end by the aforementioned sock, which i then took, full of bugs, out to the chicken coop, and fed the bugs to the girls. They were very happy about that, and so are we: there have been no further insect sightings since we accomplished that little side-project.
Then Bugeye pulled a tray of tools under the house and cut the water pipe from the bathtub where it connected to the sewer, and did the same for the sink. He capped the pipe that goes into the sewer, so now it just terminates in a flat cap. The actual drain pipe, he attached an L to, and then we fed the new pipe in through the hole in the wall, moved it till it had the right fall, connected it to the drain and let the glue dry, then came back outside and cut it to length.
To the end of the pipe on the outside, we attached another L so that the water falls directly down onto the rocks. (okay the rocks aren’t there yet, but they will be soon.)
Then we left it like that for two days—this project has been full of little gaps like that. :) I took Friday off as a mental health day, and went rock climbing saturday up near Ardantane–a much-needed break. Our work party was sunday. So Sunday, Alan, Foxwoman and myself finished digging out the trenches so that the trenches got the right amount of fall to move the water. This can be no less than 1/4″ per foot of distance, and we acheived a little over 1/2″ per foot of drop. We turned the faucet on inside and found all the slow spots, too-level spots, inadvertent dams and other problem areas, and dug around in the mud until we had all of that corrected.
Here’s Alan & Jenny surveying the trench with a line level and string, to determine the fall:
And here’s the test: the water moves! I went inside and washed some dishes, and we measured the water movement; we did the same thing with the bath. Only without the dishes. (that orange line is the cable for internet. the cable guy knows about it already. we left it exposed for him to splice back. it’s all good.)
So, it works! Next step, pumice. I’m using lava rock (scoria) which works as well as pumice (floats on water, and water will wick through it—the pores of the rock will move water upwards into the surrounding soil as well as downwards), because it was free. We got this stuff from someone on freecycle. People are always giving away their front yards on freecycle and craigslist; this was very easy to get ahold of.
Apologies for the mostly-diagonal photograph. That bush is the lilac, planted just on the other side of the pumice wick where it will get enough water. The basin, currently full of mud, will eventually contain a cut-up flower pot that protects the drain outflow from sediment, and a bunch of river rocks on the bottom, and then mulch. it won’t look like anything in particular by the time we’re done–a mulch basin with a lilac, an attractive flowering border slightly too far away from the house. we’ll work on that last part. :)
Here’s the trench with 6″ of lava rock in, and the soon-to-be-garden perched precariously on its banks:
Note the french drain at the end of the trench. I’ll get gravel to fill that in with.
Then we filled in the top layer with soil. First i selected the areas that will be walkways across the top of the garden, as we need direct access to the shed, pumphouse, and backyard. In these areas, i placed bricks on top of the lava rock, to prevent fine soil from sifting into the lava rock as human feet walk on the earth and compact it, thereby creating a dam down in the lava rock. Then we filled in the rest of the trench with soil, and layered clay (the clay we’d dug out in the first place) onto the bridge areas.
and then, planting plants! Zona and I got the perennials into the ground, and then i pulled my by-now-extensive bulb collection out of the fridge and planted those variously among the perennials. Then i mulched everything with leaves. By this point it was quite dark outside, so you don’t get process photos of that part. This morning, I got some finished-garden photos in the dawn light, though.
The front garden:
and the back:
All that work, and it looks like it just grew there. :)
The rest of the photos: