questions re: indoor gray-water systems

[momophile]

I just found out that only very strictly tested gray water systems can be used for outdoor/yard use in my area. However, indoor systems may be allowed. One example would be gray water going to flush the toilet. My question are: Who can do this for me since I know nothing about plumbing? Does anyone know anything about these systems? Are they complicated? Are they worth it?

Anyone?
Thanks!

[mojavekid]

1. Yahoo has a Peak Oil/Sustainability group,

http://tech.groups.yahoo.com/group/RunningOnEmpty2/

They discuss this and other topics related. Pretty interesting, and loads of links.

- mojavekid

[ashling]

2. I would think that any reputable plumber

would be able to do it.

Basically, you would need a tank capable of holding bathwater and kitchen sink water (as long as you don't have a garbage disposer on that line. The drain from those facilities would go into this tank. the supply line to the toilets would come from this tank (careful to keep drinking water completely seperate). You will need to have some system to pressurize this tank to keep the water flowing to the toilet. Normally, all of the drain lines are on gravity system, sloping down at about1 foot per 4 feet of run. Now if the storeage tank is not lower than all of the drains that feed into it, you would have to have some temporary storage tank where it converts to a pressurized system.

Hope this helps

[momophile]

3. that does help.

thanks. although I don't entirely understand all that you said, it does help me visualize how much room I would need for a tank and possibly placement.

[ashling]

4. Well, I was thinking about that

the tank probably wouldn't need to be much larger (if at all) that a water heater: 40 or 50gal. Each bath is maybe 10 - 20 gal., but you would be draining it all day at about 3 gal. per flush. Actually, you could use one or two used water heater tanks for this (maybe up to 100 gal for peak use, like in the morning when everybody is using the shower, etc. You would need a pressurization system that shouldn't take up too much space, so an area not much larger than a water heater closet (or 2) The cost, (and headache) would be all the replumbing you would have to do. It doesn't seem like it would be too major, but I always assume that it is going to be way more complicated than it seems at first. Well, actually, I don't ...then I wish I had. LOL

Come to think of it, you are probably going to have to have one tank to hold to stuff that drains by gravity, and a pump to pump it into the second tank (and maybe a backup. You want to make sure that your storage capacity is larger than you will ever need (so forget what I said up front ... see what I mean about assuming?) If the storeage tank were above the level of the toilet tanks, you wouldn't need any special pressurization - just the pump.

I am sorry if I am going crazy with this, but we used to have our own place in the country and I would do projects all the time. Since we sold that place and went back to school, I need an outlet for all these pent up plans LOL

anyway, good luck.