I feel that if you haven't got a trap " S bend " on your sink before the holding tank could become very un healthy and smelly
Rongela said
10:17 AM Oct 15, 2015
Are the portable purpose built grey water tanks that you can buy classed as being self contained or must the tank be permanently fitted?
Cupie said
10:26 AM Oct 15, 2015
wasn_me wrote:
D and D wrote:
There are heaps of places that an RV can be parked that don't have any rules on the discharge of grey water and some places actually encourage campers to discharge on trees and lawns. There are some places that either tolerate the discharge or, at worst, prohibit it all together. If you don't have a grey water retention system that satisfies the regulatory authority and don't wish to fit one the simple solution is to camp elsewhere. If you do have a retention system be aware that it will become septic quite quickly and should be discharged at a proper dump point, don't take it away and dump it on the ground at another camp site that allows grey water discharge.
Dave
Agree totally about grey water becoming septic (toxic) after time. If there's no valve or U bend between the sink, basin or shower & the holding tank, which there doesn't appear to be, as holding tanks are usually plumbed to existing drainage. How long before we see people becoming sick from breathing in toxins??
Drainage / plumbing regulations have been in place in household situations to stop people becoming sick. Do the same drainage / plumbing regulations apply to caravan construction?? I think not.
Cheers Pete
On my last trip to China I took particular interest in the plumbing there. (you might ask why ... After a previous trip thru Western Europe, I thought about writing a book about the strange bathroom plumbing systems that you encounter).
Well, back to my point....
I was surprised at the number of 4 star hotels that didn't have S or U bends in their plumbing from vanity basins ... at least where they could be seen.
Didn't really surprise me though, they seem very adept at the construction phase albeit without regard for OH&S stuff, but very lax with respect to ongoing maintenance. The difference between the China mainland and Hong Kong was striking. The Hong Kong people seemed to still retain some of the Western approaches to ongoing maintenance. They even obey road rules there.
Sorry about going off topic ... not.
done dreaming said
11:22 AM Oct 15, 2015
After you dump your grey water in a dump point,where does it go from there.I havn't read anywhere where it is treated after removal from the dump point or does it seep out as per a septic system where it ends in the ground any rate or does,by puting it in a dump point,automatically turn it into mothers milk.
justcruisin01 said
12:02 PM Oct 15, 2015
wasn_me wrote:
Agree totally about grey water becoming septic (toxic) after time. If there's no valve or U bend between the sink, basin or shower & the holding tank, which there doesn't appear to be, as holding tanks are usually plumbed to existing drainage. How long before we see people becoming sick from breathing in toxins??
Drainage / plumbing regulations have been in place in household situations to stop people becoming sick. Do the same drainage / plumbing regulations apply to caravan construction?? I think not.
Cheers Pete
There is a horrizontal version of a S-bend that can be fitted if you go that way; our van has one fitted as standard eq, even though we do not have a grey tank.
JC
KFT said
12:09 PM Oct 15, 2015
justcruisin01 wrote:
wasn_me wrote:
Agree totally about grey water becoming septic (toxic) after time. If there's no valve or U bend between the sink, basin or shower & the holding tank, which there doesn't appear to be, as holding tanks are usually plumbed to existing drainage. How long before we see people becoming sick from breathing in toxins??
Drainage / plumbing regulations have been in place in household situations to stop people becoming sick. Do the same drainage / plumbing regulations apply to caravan construction?? I think not.
Cheers Pete
There is a horrizontal version of a S-bend that can be fitted if you go that way; our van has one fitted as standard eq, even though we do not have a grey tank.
JC
Quite right JC, ours has one too. It is called a Hepvo waterless trap and they are very effective and reliable.
frank
wasn_me said
12:25 PM Oct 15, 2015
Thanks JC & KFT. I'll look into that. I'll fit some sort of holding tank soon & some sort of valve is mandatory. Is the valve fitted just before the holding tank? I would need 2 inlets to the tank,to stop back flow from the sink to the shower floor, so 2 valves. Is my thinking correct?? Cheers Pete
Jaahn said
12:58 PM Oct 15, 2015
done dreaming wrote:
After you dump your grey water in a dump point,where does it go from there.I havn't read anywhere where it is treated after removal from the dump point or does it seep out as per a septic system where it ends in the ground any rate or does,by puting it in a dump point,automatically turn it into mothers milk.
Hi,
The point of dump points is they are fitted to a sewer system, usually into the council system or perhaps a parks private septic system. Disposes of it safely and hygenically.
Perhaps some people here have very little idea of what the councils sewer system does or what is the point of an approved and/or correctly designed septic system. There are rules for grey water systems if seperate from black water ! Without getting into the sh*ty details, the point is to reduce the chance of breeding and transmitting pathogens to others from the waste of people. I have lived in some third world countries and let me point out the important role of councils and health regulations with their rules etc play in making Australia a great place to get around in. Perhaps some Grey Nomads know more about these things than the authorities we have set up. Perhaps ------
If people all put their grey water out on the ground where others get around, the chances of some one contracting an illness increases to a large degree. Some people are only carriers, so do not say I am good thanks, nothing to worry about here. I would be happy to have the normal rules used at anywhere I go or I bury any waste if away from the normal track.
Cheers jaahn
-- Edited by Jaahn on Thursday 15th of October 2015 01:02:34 PM
Kev Pearce said
02:31 PM Oct 15, 2015
Agree with everyone who says you either respect the rules re no grey water on the ground, or you don't stay there. End of argument, I agree. Too many people everywhere and to do with everything was to do their own thing and to hell with respecting others.
Chris61 said
03:07 PM Oct 15, 2015
navynurse wrote:
I'm just back from Carnarvon gorge and the park there requests that all grey water is directed to the trees and plants around the van sites. Allan
The caravan park at the Carnarvon Gorge welcome grey water around his tress, great give them a drink.
Some RV stops request totally self contained, do the right thing and keep in on board.
Some allow buckets and other means of collecting grey water, if you comply great
If you can't comply, don't complain, either find somewhere else or fit a grey water tank. Simple really.
brickies said
03:49 PM Oct 15, 2015
Grey water into sewerage is ok , But grey water is a no no into septic systems , In home situations you have a septic tank for black waste , And a sump for grey waste , Are all dump points hook into sewers
Hey Jim said
03:59 PM Oct 15, 2015
Yes then Bruce.
I know we are off the Topic but last years crop of 42 fruit from 2 trees, two year old. This year the heads are up to over 300mm plus, so hoping for a new record. Best mango was the size of a NRL football.Had to support it with a plastic bucket. And That's in down town Sydney to boot.
Back on topic. I'm You.
03_Troopy said
05:04 PM Oct 15, 2015
brickies wrote:
Grey water into sewerage is ok , But grey water is a no no into septic systems , In home situations you have a septic tank for black waste , And a sump for grey waste , Are all dump points hook into sewers
Ours had the grey water feeding into a grease trap, that drained into the septic tank.
brickies said
06:28 PM Oct 15, 2015
We had friends who had the same thing and had to get the septic tank pump out and start again has the detergent killed the bacteria the Plumber told them grey water should not feed into septic tanks for that reason .
Young Simmo said
06:28 PM Oct 15, 2015
I am not saying grey water is good, bad or unimportant, but the C/Pk I live in was built in 1965. And from what I believe, it was a slowly put together week-end project done by the then Ampol Petrol Station owner.. I could stand corrected there. I have been a permanent since Feb 1999 and seen quite a bit of different activity. I know for a fact some of the waste water drains are 2 Ft Diam X 2 foot deep. Then some of them are giant 6 Ft Diam X 6 foot deep monsters when they all seem to service only 2 and 4 bays. So many are blocked up and so many have the hose entry points smashed, blocked and disappeared all together. The place needs a rebuild really, but not likely. Therefore at a guess I would say maybe half the tenants just let their waste water run over the grass. So if new enforceable laws and rules don't come soon, it will be a Million dollars to patch up a 2 Million dollar business.
OK just jack up the nightly rate from $45 to $90.
Being permanents, we spent 5 grand for a septic tank with pump in 2000, and all our waste water ends up in the evaporation ponds 200 metres away.
PeterD said
07:35 PM Oct 15, 2015
brickies wrote:
1.. Grey water into sewerage is ok , But grey water is a no no into septic systems , In home situations you have a septic tank for black waste , And a sump for grey waste ,
2.. Are all dump points hook into sewers
1.. I'm not sure of the situation in other states but in NSW household grey water is divided. The kitchen water goes through a grease trap and bypasses the septic tank. The bathroom water goes down with the WC water into the septic tank. I was told that the reason for that is that the volume of water from the WC system is sufficient to clear the bowl but insufficient to carry the sewage to the septic tank so the bath and handbasin is used to do that.
2.. When dump points are located in sewered areas they will be connected to the sewer. When a sewer is not available they are installed above holding tanks.
Baz421 said
08:56 PM Oct 15, 2015
At home in van,,, grey water going onto roses. BEST roses ever seen here to date.
Grey water has been used on veggies across Aust for years. I can't ever recall a problem.
brickies said
11:40 PM Oct 15, 2015
PeterD I think adding grey water into dump point if all RV have to have Grey Water tanks could cause an over load if the dump point is only a storage tank , Also a lot of extra cost of treating Sewerage when dump point is on Sewerage , Down the track may see cost imposed on dump points
greyhoundtom said
08:15 AM Oct 16, 2015
brickies wrote:
PeterD I think adding grey water into dump point if all RV have to have Grey Water tanks could cause an over load if the dump point is only a storage tank , Also a lot of extra cost of treating Sewerage when dump point is on Sewerage , Down the track may see cost imposed on dump points
That is an extremely important consideration, and I'm sure not thought of by those advocating that all grey water goes into tanks and disposed off at dump points.
Thanks for posting as its given me something else to consider in regard to grey water disposal.
someone is just going to have to come up with a super efficient filter system that allows grey water to be filtered in the van and returned to a separate tank used for flushing the toilet. Or if it could be done well enough maybe back into the fresh water tank. Lol
All the same if cleanable filter was installed in the grey water system it may make discharging in various places more acceptable to the various authorities.
sandsmere said
08:45 AM Oct 16, 2015
Baz421 wrote:
At home in van,,, grey water going onto roses. BEST roses ever seen here to date.
Grey water has been used on veggies across Aust for years. I can't ever recall a problem.
Correct Baz.
I grew up on the family farm and the grey water always went on the gardens. I'm over 70 now and a nephew
runs the farm and the grey water is still going on the garden. Never been a problem.
rockylizard said
09:03 AM Oct 16, 2015
Gday...
Unfortunately, the cost of cleaning 'grey water' and returning it as 're-cycled' water is, at the moment anyway, a very expensive exercise.
Apart from the cost, I hesitate to imagine the added weight a 're-cycled water system' would add to RVs - which are gaining increasingly in weight with each passing year.
From my experience, and observation, the 'camps' with the requirement to be 'self-contained' are usually near or within towns and/or built-up areas. Many are on 'hard-stand' (sealed surface) and there is little, or no ability, for any water to soak away - at all, let alone quickly. Additionally, there are very few trees on such sites.
If that is so, it is obvious that discharging any liquid on the ground is imprudent, for many reasons.
In areas where there is a 'grassy' surface, the problem has arisen, I think, due to the large amount of water discharge from the large numbers of vans now equipped with all the amenities one finds in one's home. It appears that many of today's travellers with their 'fully equipped' RVs use all of their 'fully equipped' facilities - showers etc etc.
Even if this discharge were 'clean water' it creates considerable 'wet areas' that, due to the regular and ongoing use by travellers, has little chance of dissipating. This leaves an unpleasant area for those that follow - either replacement RVer's or the local populace. Add grey water to that mix and it is unpleasant, and unacceptable, for all.
It is therefore inevitable that, along the 'busy east coast' and the many towns that CMCA has convinced to be RV Friendly towns, where RVer's are being encouraged to stop and open their 'travelling wallets', the areas provided cannot cope with RVer's discharge. Consequently, and encouraged by CMCAs repesentation/marketing, towns insist on RV's being 'self-contained'. So, while banning RVs that are not 'self-contained', tents and camper trailers are also not allowed.
I am in no way denigrating CMCA and their efforts to lobby councils/towns to be RV Friendly to provide 'free rest' areas for their members, and the travelling public. However, given CMCA has been a very active promoter of 'self-contained' - Leave No Trace - it was only ever going to be that towns would see that restricting the discharge from those who use the areas they are providing is in the town's interest. A bit of a self-fulfilling prophecy really.
I travel inland, to small towns, and usually camp in camping areas away from towns - ie in areas set aside for camping. Such areas have tents and all manner of camping. These areas usually have grass and trees - and often a watercourse (creek, river, lake etc). Usually these areas have ground that is able to cope with dissipating any water.
These areas have no restriction on the discharge of water and, as many have already stated, welcome the discharge to be put on their trees. Everything thrives - the grass, the trees, the camper and the townsfolk.
It has been on rare occasions that I have encountered campers in these areas who discharge of their water thoughtlessly.
Of course, none of the above addresses the 'grey water tank' debate. However, it does provide a little thought that perhaps it is where you travel, and want to sleep, that dictates the need, or otherwise, of fitting 'grey water' tanks.
Cheers - John
aussietraveller said
09:31 AM Oct 16, 2015
It's amazing how we tend to go over the top in Australia, there is the current way over the top OH&S regulations which far exceed any other country in the world, then we have safety devices for safety devices just in case the first safety device fails the classic example is the alarm system just in case the battery in your break safe goes flat, I heard that you now have to attach bells to safety chains just in case the D shackle fails.
Now we have grey water restrictions which say if you don't have a grey water tank under your van you can't park at a free camp area, what a total load of dribble we live in a country where every drop of water weather grey, pink or blue is valuable and is great for watering trees grass and gardens, as others have already said there are a significant number of caravan parks that ask you to water trees and grass with gr water.
it would be much more valuable and environmentally friendly if all new vans were fitted with a rubbish container so the owners could help keep the roadside stops and the sides of our highways clean, we are the only country in the world where we have snow along the side of highway in arid terrain.
brickies said
09:43 AM Oct 16, 2015
I think John has nailed it the problem is were free camps are close to towns and on hard standing , It all depends on what service you are using on your RV also have seen people pull up at a free camp and get the washing machine going dropping load of water on the ground . If we do an over night we use has little water has possible in some cases don't do the washing till next stop .
scottynbulldog said
01:18 PM Oct 16, 2015
All this talk about grey water and having tanks fitted but no one has mentioned the extra weight this could cause on the van!
rockylizard said
01:37 PM Oct 16, 2015
scottynbulldog wrote:
All this talk about grey water and having tanks fitted but no one has mentioned the extra weight this could cause on the van!
Gday...
I don't know ... but logic says that if you have 60litres of fresh water and that becomes 60litres of grey water then there is no increase in the weight of the van.
.... or 60 litres of fresh > 30 litres of grey leaving 30 litres of fresh etc etc.
Of course, the installation of the grey water tank would introduce some weight ... but only a few Kg ya'd reckon
I truly doubt one would use the 60 litres of fresh, creating 60 litres of grey and then refill the fresh tank with 60 litres - therefore having grey water tank full with 60 litres AND 60 litres of fresh .... because there would be NOWHERE for the future grey water to go.
However, permutations could go on and on perhaps. Use 20litres of fresh creating 20 litres of grey; fill fresh with 20litres - use another 20 litres of fresh creating another 20 litres of grey; totalling 40 litres of grey etc etc. Then there would be additional weight for the van. Becomes frightening don't it and to think I retired and travel to RELIEVE the stress.
Cheers - John
-- Edited by rockylizard on Friday 16th of October 2015 01:45:45 PM
gypsynolmate said
03:27 PM Oct 21, 2015
Absolutely agree with Peter and Margaret. I also think, when I see so called responsible people letting their animals poop all over the place, where do you live, how would you like it, if I invite the neighbor-hood dogs over for a poop on your lawn.
03_Troopy said
09:52 PM Oct 21, 2015
gypsynolmate wrote:
Absolutely agree with Peter and Margaret. I also think, when I see so called responsible people letting their animals poop all over the place, where do you live, how would you like it, if I invite the neighbor-hood dogs over for a poop on your lawn.
Especially those bl@@dy cows, horses and sheep crapping all over the countryside. Someone should do something about it..
Wombat 280 said
06:31 PM Oct 24, 2015
wasn_me wrote:
D and D wrote:
There are heaps of places that an RV can be parked that don't have any rules on the discharge of grey water and some places actually encourage campers to discharge on trees and lawns. There are some places that either tolerate the discharge or, at worst, prohibit it all together. If you don't have a grey water retention system that satisfies the regulatory authority and don't wish to fit one the simple solution is to camp elsewhere. If you do have a retention system be aware that it will become septic quite quickly and should be discharged at a proper dump point, don't take it away and dump it on the ground at another camp site that allows grey water discharge.
Dave
Agree totally about grey water becoming septic (toxic) after time. If there's no valve or U bend between the sink, basin or shower & the holding tank, which there doesn't appear to be, as holding tanks are usually plumbed to existing drainage. How long before we see people becoming sick from breathing in toxins??
Drainage / plumbing regulations have been in place in household situations to stop people becoming sick. Do the same drainage / plumbing regulations apply to caravan construction?? I think not.
Cheers Pete
Let us not become confused with what is Toxic and what is a smell, Smell or and taste are not a measure of toxicity .
On my last trip to China I took particular interest in the plumbing there. (you might ask why ... After a previous trip thru Western Europe, I thought about writing a book about the strange bathroom plumbing systems that you encounter).
Well, back to my point....
I was surprised at the number of 4 star hotels that didn't have S or U bends in their plumbing from vanity basins ... at least where they could be seen.
Didn't really surprise me though, they seem very adept at the construction phase albeit without regard for OH&S stuff, but very lax with respect to ongoing maintenance. The difference between the China mainland and Hong Kong was striking. The Hong Kong people seemed to still retain some of the Western approaches to ongoing maintenance. They even obey road rules there.
Sorry about going off topic ... not.
There is a horrizontal version of a S-bend that can be fitted if you go that way; our van has one fitted as standard eq, even though we do not have a grey tank.
JC
Quite right JC, ours has one too. It is called a Hepvo waterless trap and they are very effective and reliable.
frank
Hi,
The point of dump points is they are fitted to a sewer system, usually into the council system or perhaps a parks private septic system. Disposes of it safely and hygenically.
Perhaps some people here have very little idea of what the councils sewer system does or what is the point of an approved and/or correctly designed septic system. There are rules for grey water systems if seperate from black water ! Without getting into the sh*ty details, the point is to reduce the chance of breeding and transmitting pathogens to others from the waste of people. I have lived in some third world countries and let me point out the important role of councils and health regulations with their rules etc play in making Australia a great place to get around in.
Perhaps some Grey Nomads know more about these things than the authorities we have set up. Perhaps ------
If people all put their grey water out on the ground where others get around, the chances of some one contracting an illness increases to a large degree. Some people are only carriers, so do not say I am good thanks, nothing to worry about here. I would be happy to have the normal rules used at anywhere I go or I bury any waste if away from the normal track.
Cheers jaahn
-- Edited by Jaahn on Thursday 15th of October 2015 01:02:34 PM
Agree with everyone who says you either respect the rules re no grey water on the ground, or you don't stay there. End of argument, I agree. Too many people everywhere and to do with everything was to do their own thing and to hell with respecting others.
The caravan park at the Carnarvon Gorge welcome grey water around his tress, great give them a drink.
Some RV stops request totally self contained, do the right thing and keep in on board.
Some allow buckets and other means of collecting grey water, if you comply great
If you can't comply, don't complain, either find somewhere else or fit a grey water tank. Simple really.
Yes then Bruce.
I know we are off the Topic but last years crop of 42 fruit from 2 trees, two year old. This year the heads are up to over 300mm plus, so hoping for a new record. Best mango was the size of a NRL football.Had to support it with a plastic bucket. And That's in down town Sydney to boot.
Back on topic. I'm
You.
Ours had the grey water feeding into a grease trap, that drained into the septic tank.
I am not saying grey water is good, bad or unimportant, but the C/Pk I live in was built in 1965. And from what I believe, it was a slowly put together week-end project done by the then Ampol Petrol Station owner.. I could stand corrected there. I have been a permanent since Feb 1999 and seen quite a bit of different activity. I know for a fact some of the waste water drains are 2 Ft Diam X 2 foot deep. Then some of them are giant 6 Ft Diam X 6 foot deep monsters when they all seem to service only 2 and 4 bays. So many are blocked up and so many have the hose entry points smashed, blocked and disappeared all together. The place needs a rebuild really, but not likely. Therefore at a guess I would say maybe half the tenants just let their waste water run over the grass. So if new enforceable laws and rules don't come soon, it will be a Million dollars to patch up a 2 Million dollar business.
OK just jack up the nightly rate from $45 to $90.
Being permanents, we spent 5 grand for a septic tank with pump in 2000, and all our waste water ends up in the evaporation ponds 200 metres away.
1.. I'm not sure of the situation in other states but in NSW household grey water is divided. The kitchen water goes through a grease trap and bypasses the septic tank. The bathroom water goes down with the WC water into the septic tank. I was told that the reason for that is that the volume of water from the WC system is sufficient to clear the bowl but insufficient to carry the sewage to the septic tank so the bath and handbasin is used to do that.
2.. When dump points are located in sewered areas they will be connected to the sewer. When a sewer is not available they are installed above holding tanks.
At home in van,,, grey water going onto roses. BEST roses ever seen here to date.
Grey water has been used on veggies across Aust for years. I can't ever recall a problem.
That is an extremely important consideration, and I'm sure not thought of by those advocating that all grey water goes into tanks and disposed off at dump points.
Thanks for posting as its given me something else to consider in regard to grey water disposal.
someone is just going to have to come up with a super efficient filter system that allows grey water to be filtered in the van and returned to a separate tank used for flushing the toilet. Or if it could be done well enough maybe back into the fresh water tank. Lol
All the same if cleanable filter was installed in the grey water system it may make discharging in various places more acceptable to the various authorities.
Correct Baz.
I grew up on the family farm and the grey water always went on the gardens. I'm over 70 now and a nephew
runs the farm and the grey water is still going on the garden. Never been a problem.
Gday...
Unfortunately, the cost of cleaning 'grey water' and returning it as 're-cycled' water is, at the moment anyway, a very expensive exercise.
Apart from the cost, I hesitate to imagine the added weight a 're-cycled water system' would add to RVs - which are gaining increasingly in weight with each passing year.
From my experience, and observation, the 'camps' with the requirement to be 'self-contained' are usually near or within towns and/or built-up areas. Many are on 'hard-stand' (sealed surface) and there is little, or no ability, for any water to soak away - at all, let alone quickly. Additionally, there are very few trees on such sites.
If that is so, it is obvious that discharging any liquid on the ground is imprudent, for many reasons.
In areas where there is a 'grassy' surface, the problem has arisen, I think, due to the large amount of water discharge from the large numbers of vans now equipped with all the amenities one finds in one's home. It appears that many of today's travellers with their 'fully equipped' RVs use all of their 'fully equipped' facilities - showers etc etc.
Even if this discharge were 'clean water' it creates considerable 'wet areas' that, due to the regular and ongoing use by travellers, has little chance of dissipating. This leaves an unpleasant area for those that follow - either replacement RVer's or the local populace. Add grey water to that mix and it is unpleasant, and unacceptable, for all.
It is therefore inevitable that, along the 'busy east coast' and the many towns that CMCA has convinced to be RV Friendly towns, where RVer's are being encouraged to stop and open their 'travelling wallets', the areas provided cannot cope with RVer's discharge. Consequently, and encouraged by CMCAs repesentation/marketing, towns insist on RV's being 'self-contained'. So, while banning RVs that are not 'self-contained', tents and camper trailers are also not allowed.
I am in no way denigrating CMCA and their efforts to lobby councils/towns to be RV Friendly to provide 'free rest' areas for their members, and the travelling public. However, given CMCA has been a very active promoter of 'self-contained' - Leave No Trace - it was only ever going to be that towns would see that restricting the discharge from those who use the areas they are providing is in the town's interest. A bit of a self-fulfilling prophecy really.
I travel inland, to small towns, and usually camp in camping areas away from towns - ie in areas set aside for camping. Such areas have tents and all manner of camping. These areas usually have grass and trees - and often a watercourse (creek, river, lake etc). Usually these areas have ground that is able to cope with dissipating any water.
These areas have no restriction on the discharge of water and, as many have already stated, welcome the discharge to be put on their trees. Everything thrives - the grass, the trees, the camper and the townsfolk.
It has been on rare occasions that I have encountered campers in these areas who discharge of their water thoughtlessly.
Of course, none of the above addresses the 'grey water tank' debate. However, it does provide a little thought that perhaps it is where you travel, and want to sleep, that dictates the need, or otherwise, of fitting 'grey water' tanks.
Cheers - John
Now we have grey water restrictions which say if you don't have a grey water tank under your van you can't park at a free camp area, what a total load of dribble we live in a country where every drop of water weather grey, pink or blue is valuable and is great for watering trees grass and gardens, as others have already said there are a significant number of caravan parks that ask you to water trees and grass with gr water.
it would be much more valuable and environmentally friendly if all new vans were fitted with a rubbish container so the owners could help keep the roadside stops and the sides of our highways clean, we are the only country in the world where we have snow along the side of highway in arid terrain.
Gday...
I don't know
... but logic says that if you have 60litres of fresh water and that becomes 60litres of grey water then there is no increase in the weight of the van. 
.... or 60 litres of fresh > 30 litres of grey leaving 30 litres of fresh etc etc.
Of course, the installation of the grey water tank would introduce some weight ... but only a few Kg ya'd reckon
I truly doubt one would use the 60 litres of fresh, creating 60 litres of grey and then refill the fresh tank with 60 litres - therefore having grey water tank full with 60 litres AND 60 litres of fresh .... because there would be NOWHERE for the future grey water to go.
However, permutations could go on and on perhaps. Use 20litres of fresh creating 20 litres of grey; fill fresh with 20litres - use another 20 litres of fresh creating another 20 litres of grey; totalling 40 litres of grey etc etc. Then there would be additional weight for the van. Becomes frightening don't it
and to think I retired and travel to RELIEVE the stress. 
Cheers - John
-- Edited by rockylizard on Friday 16th of October 2015 01:45:45 PM
Absolutely agree with Peter and Margaret. I also think, when I see so called responsible people letting their animals poop all over the place, where do you live, how would you like it, if I invite the neighbor-hood dogs over for a poop on your lawn.
Especially those bl@@dy cows, horses and sheep crapping all over the countryside. Someone should do something about it..
Let us not become confused with what is Toxic and what is a smell, Smell or and taste are not a measure of toxicity .