Why do RVs need separate grey and black water tanks ? Does your coach ?

[richard5933]

There is a stark difference between a storm sewer & a sanitary sewer and are usually plainly marked even sometimes with international symbols (ie: a "fish" pictured on the cover plate means it ends up straight into the local water source).

Sometimes yes, sometimes no. Milwaukee uses a combined system - everything goes to the sanitary sewer system. We live outside the city on septic - here all the street drains go directly to the surface water, which eventually becomes drinking water when it gets back to Lake Michigan (or percolates to the water table my well taps).

Either way, seems a good idea to keep dirty shower water out of the surface water. Can't think of it ever being necessary... You've got to go refill the fresh water and dump the black tank eventually. Just dump the gray with it.

[windtrader]

Just do the right thing - dump the tanks at proper facilities and do not put any drain from gray to ground, only to black.  Of course, in a true emergency, do what you need to do. My "emergency" procedure is to open the gray into the black just a bit, so we stay operational a bit longer. Then get to a dump station asap.

[Dave5Cs]

When we lived in Colorado Springs, Colorado we noticed at most major outside public lawn areas like the colleges, golf courses, Air force Academy, there were signs that said watered with non-Potable water, not for human consumption. They recycle water from storm drains, flash flood holding areas etc.
When I asked a guy pumping out our septic tank where they dump it. He told me they go out to the eastern plain fields about 5 miles from town and just dump while driving through the fields. He said all pathogens are dead from the suns UV rays within 24 hours. Some of the farmers use it for their fields turn it in with tillers after it has sat for 2 days and use it for compost...Eeewwww

[windtrader]

Dave - Man, that is over now it is understood just what people dump in the drain. And nobody wants that crap in compost that gets back into the food chain where we lap it up the toxins, chemical, and start glowing like aliens. lol


Proper non-potable water recycling is practiced in some places like golf courses. But the purple pipe water is still treated, just to lower standards.


My son works in public works water treatment and talks of the most recent rollout of treated recycled water for drinking. That's a lot bigger step but it is inevitable it is the future as global warming increasingly affects our water supply.

[Lin]

As I understand it, Palm Springs and the surrounding areas water their golf courses with gray water.

[windtrader]

It is treated for such use, not gray (untreated) by any means. It is all processed through the plants and sent out via purple pipe. No way is it untreated. There may be other methods for gray water reuse but that is something totally different.

[Gary Hatt - Publisher BCM]

You need to read the regulations on what ships and boats can dump in the ocean,lakes and water ways

I think the rule on boats is that if you are 3 miles or more offshore, you can dump your tanks. If you can do the same with your bus, I believe that would be okay.

Just remember to close your valve before you head into port. 

[Dave5Cs]

Dave - Man, that is over now it is understood just what people dump in the drain. And nobody wants that crap in compost that gets back into the food chain where we lap it up the toxins, chemical, and start glowing like aliens. lol

Windy not from the drains re-read post from pumping out septic s.

[Dave5Cs]

I think the rule on boats is that if you are 3 miles or more offshore, you can dump your tanks. If you can do the same with your bus, I believe that would be okay.

Just remember to close your valve before you head into port. 

Agree our Buses are one piece on the bottom right? so they must float right?

[windtrader]

Windy not from the drains re-read post from pumping out septic s.

Ah, even worse. In CO today, that'd get you put in the slammer for a long time.

[Jim Blackwood]

Does a bear sh!t in the woods? Deer? How about fish and frogs and nastier aquatic creatures? Industrial chemicals that never die? (I've heard DDT is making a comeback) Given all that, I'd say we are responsible first and foremost not to put industrial chemicals in the water and after that it becomes a sliding scale. So what about the biggest industrial chemical we have, Gasoline? Does anyone today truly believe that there is nothing harmful left after it goes through a catalytic converter? I doubt it. But at least we've cut down on that. And that raises the question of how much is too much, which applies across the board. The historic answer has always been, how much can you live with? We are creatures of convenience and will rarely go beyond the necessary, at least on a group basis. So given the polluted world we live in, is some gray water in the grass going to have any impact at all? I think sometimes it will and sometimes it won't. Mostly it won't. Unless you happen to be loaded with long lived pathogens in which case maybe you should be taking extra precautions.

Speaking of which, that points out another disadvantage of a single holding tank. If you add a diverter to drain away the gray water, you now have very little control over timing, as in when and where the gray water goes to ground. It'll go when it is used, which could end up being irresponsible. Like if you forgot to divert it back to the waste tank and someone takes a shower while you're sitting on the Walmart parking lot in the middle of the day. Or even just having water running out of the RV when people are walking by. With separate tanks that should never come up. You could drain at night or during a rainstorm if you like, the point is you can wait and pick your time.

But should you drain graywater during a rain? Well completely apart from the camoflage, it dilutes the gray water, lowering the concentration of soaps and dirt. Since the very definition of Earth is dirt, I really don't see the dirt being much of a problem, the other primary concern is human specific pathogens, in particular things like cholera that can survive in groundwater. Best rule of thumb there, if you are sick don't dump graywater. It's more a matter of the concentration of the pathogens than their absolute elimination which we will never do anyway in most cases. Then the soaps. Do you know what makes a soap? It's a base and a fat. The base can be a wide range of things, an alkali, lye which can be derived from wood ashes, phosphates etc. The point is these are things that exist in our environment, and they do not cause a problem until there are too much of them, just like anything else. Again it is concentration that is the issue, so the more it is diluted the less of an issue it becomes. Doing things like burning the contents of the black water tank which concentrates these components is probably making the disposal problem worse, not better.

So is sending the gray water to a central location where the components can be concentrated a good thing? I'd say only if they can then be separated out and reused. Otherwise it creates a disposal problem similar to nuclear waste.

Jim

[richard5933]

Does a bear sh!t in the woods? ...

Jim

Jim - You and the others can defend and explain this all you want. There's no getting around that dumping untreated gray water has potential problems. My mom used to wash our cloth diapers in the sink before putting them in the washing machine - that is gray water. Every time we shower fecal matter is in the gray tank. There's no way to explain away the fact that gray water is not clean water. Yes, it's legal dump to the ground in some jurisdictions. Great. Because it's legal doesn't necessarily make it a good idea.

Countless cases of disease have spread through the wilderness areas through improper disposal of human waste. Countless vegetable crops have been contaminated with field workers crapping in the fields.

Agreed - dumping an RV's gray tank is low on the scale when compared to DDT, but that's not a fair comparison. Just because mega-corporations pollute more than a little guy doesn't mean it's okay for the little guy to pollute.

Again, it's amazing how we as a species of that special knack of peeing and crapping in our drinking water.

[luvrbus]

They don't treat rain or run off they do everything possible to keep run off or rain water from entering a sanitary sewer treatment plant.There is huge different in treated and recycled water all the car washes in AZ use recycled water ran through filters,in the west lot of towns use recycled sewer water on golf courses but you don't drink or lick your balls,treated sewer once it leaves the drying beds in a solid form is still used in fields lol and you probably bought a bag before at Lowes or H/D and never knew it.Watching what comes out of a storm drain outfall line into creeek,river or lake a little gray water is the least of our worries

[Jim Blackwood]

I think you misunderstand me Richard. All I'm saying is to use some common sense, and that works both ways. We should avoid making things worse but we should also realize that sometimes the cure is worse than the problem, as in bypassing treatment plants during times of high runoff for instance. How could it possibly be better to dump concentrated sewage in the water supply rather than widespread dispersion of gray water before it ever gets there?

As a species we are pretty resilient. It takes a rather concentrated dose of anything to hurt us, and sometimes lengthy exposure as well. So the concentration is the key. One bacterium will not do it. That will get killed off as soon as it makes contact with us, if it makes contact. Which is a good thing because otherwise we would have all died long ago. The problem comes when that stuff gets concentrated enough to overcome our natural defenses and that takes some doing. Now what does your shower do? It dilutes oils, dirt and such, often including a very small amount of crap. At least we sure hope it's a small amount. (btw if anyone is still using cloth diapers it'd be a good idea to put the rinse water down the toilet instead of the sink drain, especially since that's where you wash your dishes.)  Diluted is better. It's safer. The more diluted it is, the less dangerous. So what we need to be working towards is dilution rather than concentration.

Unfortunately the holding tanks aren't helping us there very much. I don't know anyone who has tested the concentrations of pathogens in sewage but it's probably available online. Common sense says some will increase over time, some will decrease, some will be eliminated by anerobic decomposition, some by aerobic, some vice-versa. But without knowing for sure it's mostly shooting in the dark. What we do know is that gray water's threat level is way way below that of black water, and possibly low enough that we could wash our hands in it with no adverse effect. After all, you take a shower in it don't you? Not that I'd recommend that, but treating it like it's radioactive is not a sensible solution because it will lead to draconian measures that are not justified and unintended consequences like overflowed treatment plants.

In all probability the only way a person could be brought to harm by contact with gray water would be to drink it or swim in it, neither of which is going to happen if it is used to water the trees and shrubs. And for the record, they like the fertilizer as well. Agriculture has a long and fruitful history of fertilization with waste products, both animal and human. Today we try to avoid using human waste because it may contain bacteria that infects us but that hasn't slowed the use of animal waste. Urine still has many uses and historically was a widely used supply stream for the manufacture of explosives like black powder. These uses were accomplished without decimating the lives of the citizenry, so more or less safely. In fact they tended rather to improve society rather than to harm it.

So all I'm saying is to think about what you are doing and know your facts. The wonderful earth saving goal you are enamored with just may be a bit tarnished.

Jim

[luvrbus]

Ah surface water is the reason I don't drink Budweiser beer lol I seen what surface water from Lake Houston looks like