I've been thinking a lot about how practically sustainable an urban house could be. So we have to think about the types of things that come into a home as far as resources and the types of things that go out of that home.

So let's go with water first. You have your city water line in most cases.

Again, this is for an urban home so in that case for sure you have a

city water line. That water comes in and how is that water being used? Well

typically you're going to go into the shower and bath, any sort of sink and

mostly a laundry situation after that.

Those are probably your biggest three uses of that water.

Now what happens to that water afterwards?

Well the shower goes down into the sewer, the shower goes down into the sewer,

the sink goes down to the sewer,

and so does the laundry machine.

So all that goes untreated down into the sewer.

Now, of course, it will go to the wastewater treatment plant most likely and get treated at that point but you know we want to think about can we reroute this?

Well the most standard way to reroute from my research seems to be the laundry conversion.

It's a very simple one and most municipalities will offer you a rebate or they'll cover the cost of what we call a

gray water laundry conversion project. What you're doing there is you're putting in a three-way valve.

What that three-way valve does is it says, okay, you can either route this laundry wash down to the sewer as it would normally go or if you flip it the other way

you can route it out of the house down into a graywater system.

Now that gray water system could be a holding tank that then pumps it out into the surrounding landscape for irrigation

or it could just go directly there without any sort of holding tank.

Now I know people, my friend Anne from Real Hands of O.C.

does this, where they've unhooked their sink,

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