It never occurred to me, why not just one tank?

[Ljwt330]

Originally Posted by Persistent

In most home sewage systems there is a 6 to 8 foot drop between things like lavatory and sewage outflow or holding tank. In an RV, there may be 4 feet and the sewage outflow is designed to be closed off.

Back up of black water can easily flow into sinks and showers when not operated correctly. Two tanks prevents dangerous black water from getting into sinks and showers where it could contaminate food, water, and people.

This brings up another point. Since the inclusion of showers in RVs, that would be the lowest point of intrusion should a single tank overfill. Unless there was a waterless trap in the drain line of the shower, black water would enter through the floor of the shower.

[Mr.Mark]

I wish my 'B' had the black and grey tanks combined.

On my Prevost Liberty Coach, I had one holding tank and one fresh water tank, 189 gallons each. I also had a 'grey water bypass' where I could let grey water run on the ground (if allowed) or connect a hose to the outside spigot to water a tree/grass.

On the 'B', it would give me more capacity for regular RV park dumping as I have 11 gallon black and 35 gallon grey, 24 gallon fresh.

Safe travels,
Mark

[Ldubs]

Originally Posted by Jay D.

you don't dump gray water in OREGON. you will, might get a hefty fine.
Jay D.

California also prohibits dumping of grey water. However, I was at a National Forest campground located in California that allowed dumping of gray water. They said they preferred it not be dumped, but if needed it should be collected in a bucket and spread around the campsite.

[0rion]

I welcome the separate tanks....if I misjudge my dump and have it back up in the shower I feel alot better about that on my feet than if the black was mixed in. I do wish they would put wash outs on the grey tanks though. Our last one had 2 grey tanks...one was for the kitchen and back bedroom. No matter how diligent one is there's just inevitably going to be some food go down the drain...I'd like to have been able to flush that tank.

[Kenrbass]

I have seen a few people use a composting toilet and change both tanks to grey.

[emiddleb]

I might not be normal (ask the wife) but I find when we stay for a week or more with full hookups we tend to generate a lot more grey than black. Showers etc. I've been in the habit of leaving my grey open until a day or so before the black fills so I'll have some to rinse after dumping the black. I like the separate tanks.

[Marine359]

Since we have small waste tanks and often boondock, the dw calls me the water Nazi. She accused me of sitting outside the shower and counting the time the shower was running. Maybe I’m too old to remember doing that. It’s easy enough to go fetch some water to replenish the fresh tank, but I admit I’m a bit OCD about creating more gray water than needed, but now she’s trained to take a shower on 6 gallons. If we both shower every other day, it means I have to break out the waste tote, and tow the gray water away with our TV. Bit of a hassle, but no big deal unless there’s no nearby dump station. I’ve heard that some people put the tote in the truck bed and use a macerator to pump waste water up into the tote. Wondering if that actually works?

[ArtJoyce]

Originally Posted by EdInArk

I don't know if it's a consideration for the manufacturer, but some COE parks allow grey water to be dumped onto the ground, but obviously not black. You'd need separate tanks there.

+2. Many places use to allow dumping gray on the ground. I have done it many times in my 30 years of camping. There are fewer places that allow it. Plus some of the bonebocking locations use to let you dig a hole and dump the gray and cover it up when you left.

[shootist]

Originally Posted by Jay D.

you don't dump gray water in OREGON. you will, might get a hefty fine. the DEQ considers gray water more of a hazard than your black water .
Jay D.

There isn't much about oregon that I care for. Grey water without food in it is harmless to your front yard.

[twogypsies]

We volunteered in Sleeping Bear Dunes Nat'l Lakeshore in Michigan. There was a problem at the water spigots throughout the park of not draining... always puddles. One of our 'jobs' was to dig out the rock and some of the dirt and replace with clean. You would not believe what toothpaste, hair washing and washing a few dishes creates. Believe me, it was not a pleasant job. Signs at these spigots obviously didn't do a thing. Grey water is awful!!! Please don't dump it on the ground.... especially in a campground where others park in the same spot. It also attracts ants and other critters.

[ArtJoyce]

Originally Posted by Persistent

In most home sewage systems there is a 6 to 8 foot drop between things like lavatory and sewage outflow or holding tank. In an RV, there may be 4 feet and the sewage outflow is designed to be closed off.

Back up of black water can easily flow into sinks and showers when not operated correctly. Two tanks prevents dangerous black water from getting into sinks and showers where it could contaminate food, water, and people.

That is a good point. I bet I over filled my gray tank at least 20 times in 30 years. It always was gray water coming out of the shower drain when I went camping with 4 kids.

[Raider47]

Originally Posted by twogypsies

We volunteered in Sleeping Bear Dunes Nat'l Lakeshore in Michigan. There was a problem at the water spigots throughout the park of not draining... always puddles. One of our 'jobs' was to dig out the rock and some of the dirt and replace with clean. You would not believe what toothpaste, hair washing and washing a few dishes creates. Believe me, it was not a pleasant job. Signs at these spigots obviously didn't do a thing. Grey water is awful!!! Please don't dump it on the ground.... especially in a campground where others park in the same spot. It also attracts ants and other critters.

Good to know, thank you.
There is an article on Truckcamperadventure.com about modifying your rv shower to recirculate water through filters. I don't think that I will take it that far but I am considering attaching a hose and filter to the grey water drain and using that water for flushing the toilet. Does anyone have experience with this?

Edit: I Don't mean to threadjack if this is too far off Subject, please let me know.

[Ray,IN]

Originally Posted by Argosy

Weight distribution, size, tank weight, and cost. There's a lot to fit in/under an RV, two smaller tanks are easier to fit than one large one. Costs go up fast when a tank gets larger, the manufacturing equipment is larger, the walls have to be thicker, production time is longer per piece.

My MH has 3 fresh water tanks, one black and one gray. The 3 fresh water tanks are positioned around the engine and plumbed together to fill all voids under the floor around the engine. gray and black tanks are forward of the fresh tanks.
When we were in Quartzsite several years ago the RV park desk requested we water their plants and trees near our site with our gray water.

[move on]

I don't think gray water is necessarily dangerous or obnoxious. It depends on how far you are from other people. Heck, even black water is OK if you are far enough from civilization. Does a bear sh_t in the woods?