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@Sparky617 You can't even route gray water to toilet tanks?
I can't speak to what is permissible everywhere. Here you could not run a separate water system to reuse gray water. If you wanted to capture it in a bucket, say from your washing machine and use it to manually flush a toilet I'm sure they couldn't stop you. But to actually plumb a tank into the system, along with a pump and pressure tank to move it through pipes and a separate piping system to your toilets for using gray water, that would be illegal.

They are allowing gray water systems in some large commercial office buildings because they'll have professional maintenance to keep the systems running. Our town installed a reclaimed water system from the nearby sewage treatment plant. We can use that water, had they plumbed my neighborhood, for irrigation of grass and commercial buildings can use it for chiller plants. They could also use it for flushing toilets, but that would have to be built into the building as it was being built. Retrofitting would be cost prohibitive. I wish they had plumbed my neighborhood, but they started with a more expensive neighborhood closer to the plant and the people complained so much about the mess and the repaving job they did on the streets that they stopped doing existing neighborhoods. The two neighborhoods adjacent to mine were being built new when the system went in and they have the reclaimed water system. It saves you on sewage charges if you have a irrigation system. Plus you're not wasting potable water on grass.
 
But to actually plumb a tank into the system, along with a pump and pressure tank to move it through pipes and a separate piping system to your toilets for using gray water, that would be illegal.
Ah, interesting. Also about the reclaimed water system in your town.
It saves you on sewage charges if you have a irrigation system. Plus you're not wasting potable water on grass.
Yeah, that was the main thing I was thinking of. Well, not irrigation or even watering grass, but watering plants/flushing toilets.
 
The reclaimed water system was built to allow them to expand our fresh water plant. We pull water from Jordan Lake part of the Cape Fear River system. But we discharge it into Crabtree Creek part of the Neuse River system. So it is a inter-basin transfer and to get the Army Corp of Engineers to approve the expansion we had to do the reclaimed system to reduce some of the demand for water and reduce the amount of inter-basin transfers since irrigation water doesn't flow directly into the streams and rivers like 99% of water consumed inside the house does. The vast majority of residential water is for flushing toilets and clothes washing. Dishwashing and drinking to a much less extent. Once they got the approval to expand the plant the replumbing of existing neighborhoods came to a halt. Hmm, why could that be? On clothes washing, when we went from a top loader to a front loader our water usage dropped by 20% for a family of 4. That was a 1000 gallons a month saved.

We keep a bucket in our bathtub to catch the cold water while waiting for hot water to reach the sink. My recirculation pump died and I haven't gotten around to replacing it. We use that water to flush the master bathroom toilet. Not gray water, but water that would have gone to waste otherwise. Running it out the bath tub also gets the hot water to the bathroom much faster than turning on the shower with the low-flow shower head.
 
If you are on public sewers they want all the water back they send out and using it twice in most of the country will not produce enough savings to be worth the expense IMO.



Now if you are on a well and septic it is a different situation. You are returning all the water back to where it came from to some degree. I redid my septic system at my old house shortly before the regulations changed many years ago and I wanted my gray water separated from my actual sewage. I didn’t want the soaps and cleaning products added to my septic breakdown process. On the other hand I didn’t want the gray water to go directly to the leach field. I placed a tank I call a grease trap right before the leach field. The outflow of the septic tank goes to this tank as does the gray water. The tank is standing on end and is 24” dia x 10’ long and comes above grade and has a lid. I use a drop tube so that the outflow comes from the middle of the tank so stuff can sink or float.



When I have my septic pumped I also have the grease trap pumped. There is a cake on the top and several feet of waxy sludge on the bottom. All that would have been plugging up my leach field had I not done it this way.

I’m told my system is grand fathered in but if someone wanted to do this today they would not be allowed.
 
If you are on public sewers they want all the water back they send out and using it twice in most of the country will not produce enough savings to be worth the expense IMO.

In many areas, especially in the arid west reclaimed systems make a lot of sense. Watering golf courses, yards, roadway plantings with precious drinking water makes no sense. They might be able to use reclaimed water on certain crops but you can't use it on some of the stuff California is really good a growing like produce. I think to use it on those would require another step in the reclamation process. I see signs out in the SF Bay area that announce that many of the roadside plantings are being watered with reclaimed water.

Trying to save the water from our washing machine and possibly showers might produce enough water to flush one of our toilets consistently. With just my wife and me in the house now and using a front loading washer I doubt we'd get enough to make it worthwhile if it was even allowed. We're on public water and sewers.
 
In many areas, especially in the arid west reclaimed systems make a lot of sense. Watering golf courses, yards, roadway plantings with precious drinking water makes no sense. They might be able to use reclaimed water on certain crops but you can't use it on some of the stuff California is really good a growing like produce. I think to use it on those would require another step in the reclamation process. I see signs out in the SF Bay area that announce that many of the roadside plantings are being watered with reclaimed water.

Trying to save the water from our washing machine and possibly showers might produce enough water to flush one of our toilets consistently. With just my wife and me in the house now and using a front loading washer I doubt we'd get enough to make it worthwhile if it was even allowed. We're on public water and sewers.
I was down in Mexico on business a number of years ago and in a new modern factory. I went in the men’s room and was puzzled as each stall had a covered waste basket and on the door was a sign showing a wad of TP and the toilet with the red circle and line thru it “No” symbol and next to it the basket with the wad of TP going into it from a hand. I sat there for some time thinking what exactly do they want me to do here. I got brave and peaked in the can and yes that’s what they wanted me to do alright.



After finishing up in there I ran into the plant manager that moved down there from the states and I asked him what was up with wanting soiled TP in a plastic bucket instead of flushing and was told the waste was liquefied and used for irrigation and the paper clogged the spray heads. I thought ok when in Rome.



The next morning I arrived at the plant to a strong sewage smell and saw watering going on at the nearby worker daycare area and they were spraying a playground and soccer field. When I went out at lunchtime the playground and soccer field were full of kids playing.



Made me glad I live near the Great Lakes and in the northern states and also made me start reading where the fruits and veggies I’m eating were grown.

I saw a show on a waste treatment plant in our country where the discharge water into the river was 10 times cleaner than the drinking water spec of the plant next door. They asked why was the water being dumped in the river rather than piped to the drinking water treatment plant? The answer was who wants to drink cleaned up sewer water. To that I thought I guess the next town down river.
 
I saw a show on a waste treatment plant in our country where the discharge water into the river was 10 times cleaner than the drinking water spec of the plant next door. They asked why was the water being dumped in the river rather than piped to the drinking water treatment plant? The answer was who wants to drink cleaned up sewer water. To that I thought I guess the next town down river.

Just about everyone is downstream from a sewage treatment plant. The action of the water going down the river does aerate the water and further purifies it before it goes though the fresh water treatment plant. That said, the cleaned sewage water going into the stream/river is probably cleaner than what's already in it, between yard chemicals, run-off from paved surfaces, pet wastes washing into the streams etc.
 
I have considered routing the washing machine drain into my woods but hate to add a wall penetration. I don't run the washer more than once per week. When I built my house I asked my plumber to route the utility room drain to the exterior of the slab. He wouldn't do it but said I could do whatever I wanted to after he left the premises, but I didn't do it. In those days detergents used phosphates which might have been bad for surface runoff.
 
It would but it is generally not allowed. Even diverting your washing machine away from your septic tank is illegal. It was done quite frequently, running it directly into the leach field to not dilute the bacteria in the tank digesting the black water. But it isn't legal.
This may change as technology changes. And in poor countries where the citizens have long standing immunity to caca, it's not necessary.

[Some rich guy who shall remain nameless] may already have an automatic system like this because he can afford it, b/c he's vain, & b/c he can proly tell the Guv, Local or National, what to do.

I have some evidence that my mortgage co. told the USPO what to do.
And they listened. :(
 
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I would think (hope) showering figures in there somewhere...
With low flow shower heads unless you're taking 20 minute showers you're not using a lot of water. A top loading clothes washer uses around 50 gallons a load. A modern toilet uses 1.5 gallons per flush, if it flushes everything in one try. Most people use the toilet more times per day than a shower. A 5 minute shower would use less than 10 gallons of water. Hence my statement. If you're a regular bath taker you probably use 30 gallons a bath.
 
With low flow shower heads unless you're taking 20 minute showers you're not using a lot of water. A top loading clothes washer uses around 50 gallons a load. A modern toilet uses 1.5 gallons per flush, if it flushes everything in one try. Most people use the toilet more times per day than a shower. A 5 minute shower would use less than 10 gallons of water. Hence my statement. If you're a regular bath taker you probably use 30 gallons a bath.
50 gallons a load for clothes washer sounds really high. Are you sure about that?

Meanwhile, it feels like a 5 minute shower uses more than 10 gallons of water though of course I haven't checked, and most showers in my house are about twice that long.
 
50 gallons a load for clothes washer sounds really high. Are you sure about that?

Meanwhile, it feels like a 5 minute shower uses more than 10 gallons of water though of course I haven't checked, and most showers in my house are about twice that long.
Look at the size of the tub in a top loader. Throw a five gallon bucket of water in it and see how full it gets. In most wash cycles you fill it twice, once to wash and once to rinse. Front loaders use less water, by a wide margin. When we had 2 kids in the house we probably did 10 loads a week. Low flow shower heads limit you to about 1.5 - 2.5 gpm.

In a house trying to build an effective gray water system isn't cost effective. You wouldn't use kitchen sink water, dishwasher water, and likely not bathroom sink water either. Showers and clothes washing would be about it. If you want to save water, trade in your top loading clothes washer for a front loader. In an office building you might see savings with a gray water system that did minimal cleaning to bathroom sink water for use in the toilets. I'd think it would have to be a fairly large office to make it economically viable though.
 
Two gals/min for 5 mins is 10 gals.

The commercial people can play by different rules because large agencies know not to con them. And Economy of Scale.
 
Look at the size of the tub in a top loader. Throw a five gallon bucket of water in it and see how full it gets
I'm willing to believe you're right just because you've probably looked at the numbers and I know I haven't. Just thinking about how if I am trying to fill a bucket with water, it takes more water to fill it if the bucket is empty than if the bucket has a couple towels stuffed in it. Displacement. When I do laundry my machine is usually at least 2/3 full, and it has one of those "auto sensors" that varies how much water it uses based on how full it is (though I admit I don't know how it works, and it locks the lid so I can't peek, so it might be a scam).

But "gray water system is probably a no go", got that part loud and clear by now.
 
I'm willing to believe you're right just because you've probably looked at the numbers and I know I haven't. Just thinking about how if I am trying to fill a bucket with water, it takes more water to fill it if the bucket is empty than if the bucket has a couple towels stuffed in it. Displacement. When I do laundry my machine is usually at least 2/3 full, and it has one of those "auto sensors" that varies how much water it uses based on how full it is (though I admit I don't know how it works, and it locks the lid so I can't peek, so it might be a scam).

But "gray water system is probably a no go", got that part loud and clear by now.
Here is an article about it. Newer top loaders without an agitator use less water than older machines down to around 20 gallons versus 40 or more in a model that is 20 years old. My brother has one of the new top loaders and it seems to be more like a front loader but does use more water.

https://prudentreviews.com/how-much...oad washers use,average 19.6 gallons per load.



Top-Load vs. Front-Load:

In general, front-load washers are significantly more water-efficient than top-load models.

According to the ENERGY STAR database, front-load washers use an average of 12.5 gallons of water per load, while top-load washers average 19.6 gallons per load.

Top-load models from 20 years ago could use 40 or more gallons of water per load.

Top-load machines use more water because they usually fill the drum and use an agitator (more on this next) to clean the clothes.

Instead of filling the drum with water, front-loaders spin vertically, which creates space and allows water from impellers to spray and clean the clothes.
 
Most people want the water sitting in the tank and bowl of their toilet to be fresh water. I know I do. I would suspect the inside of the tank and the fill valve would look like the inside of my grease trap or the inside of my P trap under the sink in short order using gray water.
 
@Sparky617 My washer is maybe 4 or 5 years old, so that's good to know. Also for next time I'm in the market, this would bias me more toward front-loaders.

@bud16415 That's a good point! I was thinking the water from my sink, if I collected it once in a bucket, would look basically clear and clean -- but you're right, I have no further to look than the P trap to see exactly what the cumulative effect would be.
 
@Sparky617 My washer is maybe 4 or 5 years old, so that's good to know. Also for next time I'm in the market, this would bias me more toward front-loaders.

@bud16415 That's a good point! I was thinking the water from my sink, if I collected it once in a bucket, would look basically clear and clean -- but you're right, I have no further to look than the P trap to see exactly what the cumulative effect would be.
On my bathroom sinks and to a lesser extent the shower drain it isn't so much the trap as the tail pipe directly below the drain. These get scummed up from soap scum, shampoo, toothpaste spit, hair and god knows what else. I've had slow drains and usually the trap is clear, it is the tail pipe getting closed with this slow build up. If I remember I try to throw a large pot of boiling water down these drains every few months to hopefully take some of the build up away. The gel type drain cleaners tend to do a decent job since they stick to this material.
 
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