boondocking tank capacity questions for 30 days?

[baadpuppy]

My fiancee and I are converting a bus into an RV, and she's doing all the 3D modeling (in sketchup) while we work on finalizing the plans.

We've just reached the point where we need to determine tank capacity.  This is for all 3 tank types.

Our goal is to be able to live off grid for at least 30 days at a time.  Neither of us minds water conservation, but we also have pretty much no clue how best to calculate what tank sizes we will need.  It isn't like our existing septic systems will let us measure our "production" levels.

We have approximately 189" x 84" x 18" of space in which we can put tanks and associated plumbing.  Any space not used by tanks will be dry goods storage, so we don't want to just fill the entire space with tanks.

What this space boils down to is 5 "slots" of 24" x 18" x 84" and 2 "slots" of 24" x 18" x 60".  All 7 slots are accessible from the outside, and would permit the tanks to be removed for repair/replacement.

Needless to say, that's a lot of volume, which translates to a lot of gallons potential.  More gallons = more weight, so we don't want to go nuts.  More volume taken = less available for cargo, so again, we don't want to go nuts.

So what would the more experienced boondockers among us recommend for 2 adults and perhaps 4 furkids (fresh water required) for 30 days?

Thanks in advance,
jim

 

[jje1960]

My fiancee and I are converting a bus into an RV, and she's doing all the 3D modeling (in sketchup) while we work on finalizing the plans.

We've just reached the point where we need to determine tank capacity.  This is for all 3 tank types.

Our goal is to be able to live off grid for at least 30 days at a time.  Neither of us minds water conservation, but we also have pretty much no clue how best to calculate what tank sizes we will need.  It isn't like our existing septic systems will let us measure our "production" levels.

We have approximately 189" x 84" x 18" of space in which we can put tanks and associated plumbing.  Any space not used by tanks will be dry goods storage, so we don't want to just fill the entire space with tanks.

What this space boils down to is 5 "slots" of 24" x 18" x 84" and 2 "slots" of 24" x 18" x 60".  All 7 slots are accessible from the outside, and would permit the tanks to be removed for repair/replacement.

Needless to say, that's a lot of volume, which translates to a lot of gallons potential.  More gallons = more weight, so we don't want to go nuts.  More volume taken = less available for cargo, so again, we don't want to go nuts.

So what would the more experienced boondockers among us recommend for 2 adults and perhaps 4 furkids (fresh water required) for 30 days?

Thanks in advance,
jim

30 days without service (fill/empty) ???  I can't for the life of me figure out how one person could be accommodated on that let alone two.  Personally, my only experience with extended dry over a week with 2 was one year at Bristol.  If I remember right, we went a week with 48 gal of fresh water (which dripped out of the grey all week) and a pretty full black (30gal) tank that we had pumped at the end of the week.  Let me know how you figure this out, should be interesting...  Think there is going to be a lot of trips to the woods in that 30days.

 

[Molaker]

Not counting toilet flushing and the furry kids needs, the average adult requires at minimum 4 gals of water a day for drinking, cooking and hygiene - 4x that is recommended.  But let's be real frugal and say 4 gals per day per individual.  4 x 2 x 30 = 240 gals.  Water weighs about 8.4 lbs/gal.  8.4 x 240 = 2016 lbs.

You can take it from here and figure just how much weight you want to carry as water and what size tank(s) it would take to do it.  Keep in mind you do not have to consider the weight of all tanks when full.  Just the fresh water, assuming you dump your waste every time you fill your fresh water. 

Personally, I would plan on an occasional run for supplies and waste dump.

 

[baadpuppy]

Total space available for tanks, if we used it to the max, is about 1009 gallons.  Yes, that would be about 8300 pounds, and that would need to be considered when loading it... although that would be if all were full.  As was pointed out to me, the liquid starts in the fresh tank and moves to grey and black tanks.  Therefore i should consider that number to be halved, leaving 504.5 gallons for fresh water.

We would be doing navy style showers at least once a week.  Dishes would be paper, aside from cooking stuff.  Wet wipes will suffice for washing our hands after bathroom trips.  The marine type toilet we're considering is very frugal on water usage.

There's a possibility that the volume of space might end up double what we're currently considering, which would mean a total tank volume of 2018 gallons, or a max of 1009 gallons of water.  Basically, in this conversion, we can do pretty much what we want within the limits of engineering.

Does a water conserving dry camping RVer really use 4 gallons per day per adult?  I would think most of the numbers for "typical human consumption" figures would be based on typical stick and brick type houses, without any conservation being practiced.

Thanks again for all the advice,
jim

 

[Molaker]

Actually, if one believes the data in the link I provided in my 1st post, 4 gals is considered the bare minimum and that is regardless of the dwelling.  In fact, the website is addressing "world" water needs.  No doubt, one can survive on much less than 4 gals a day.  However, to maintain reasonable conditions without jeopardizing your health, you should plan on 4 gals. minimum.

Another possible way to meet your needs would be to camp in areas where reasonably clean fresh water is available (mountain streams, clear lakes, springs, etc.).  These sources are probably still not clean enough untreated, but there are various ways to purify water on-site to supplement what you take with you.  The space and weight requirements for such purifying methods would probably be much less than the space & weight required to take along adequate water for 30 days.

Along these lines, since you are building your RV from scratch, more or less, you could build in a separate water tank to hold non-potable water used for bathing and toilet needs.  This could be filled from a nearby water source bucket-by-bucket (what else were you going to do all day for 30 days).  That way you would only have to take enough for drinking & cooking needs - roughly 2 gals per day per individual.

 

[AndyinLexington]

Jim:  My wife and I and our 7 year old son can go approximately one week with our 70 gallon fresh water tank.  At the end of the week, gray and black tanks are nearly full and the fresh is nearly empty.  I shower every day (navy style), my wife and son every other day (not navy style).  We don't drink any of the tank water at all - we use bottled water for drinking, cooking, and brushing our teeth.  I figure 3-4 commode uses per person per day.  I think you will cut the consumption way down with the showering schedule you stated.  Our drinking & cooking use is about 1-2 gallons per day for the three of us.  We use paper plates and plastic utensiles that we buy at Sam's Club, paper towels and a spray bottle for cleaning up the kitchen, table, etc.  500 gallons of water seems like an awful lot to tanker around.  If I were doing your project, I'd be thinking in terms of maybe 150 gallons at the most.  There is a practical limit in terms of weight.  In addition, you might want to consider splitting it into two separate tanks if you are tanking that much.  Put one on each side of the bus to balance the weight.  You can do the same with gray/black.  One on each side of the bus.

Dump Schedule - you may want to consider dumping the black/gray water more frequently anyway just because of odor.  We find that after a week, it's starting to stink if it's getting anywhere near full. 

 

[Utclmjmpr]

I recently sold a GMC PD4106 converted bus(by me) potable water 160 Gal.,  combo grey/black 160 Gal. Wife (1 dog)and I out 3 weeks with no problem,, never did come close to filling any tank, so toward the end we would take 100 Gal. water and adjust from there for two to three weeks.>>>Dan

 

[jje1960]

Jim:  My wife and I and our 7 year old son can go approximately one week with our 70 gallon fresh water tank.  At the end of the week, gray and black tanks are nearly full and the fresh is nearly empty.  I shower every day (navy style), my wife and son every other day (not navy style).  We don't drink any of the tank water at all - we use bottled water for drinking, cooking, and brushing our teeth.  I figure 3-4 commode uses per person per day.  I think you will cut the consumption way down with the showering schedule you stated.  Our drinking & cooking use is about 1-2 gallons per day for the three of us.  We use paper plates and plastic utensiles that we buy at Sam's Club, paper towels and a spray bottle for cleaning up the kitchen, table, etc.  500 gallons of water seems like an awful lot to tanker around.  If I were doing your project, I'd be thinking in terms of maybe 150 gallons at the most.  There is a practical limit in terms of weight.  In addition, you might want to consider splitting it into two separate tanks if you are tanking that much.  Put one on each side of the bus to balance the weight.  You can do the same with gray/black.  One on each side of the bus.

Dump Schedule - you may want to consider dumping the black/gray water more frequently anyway just because of odor.  We find that after a week, it's starting to stink if it's getting anywhere near full.

Some very good advice here.  However, back you your original spec's and reality, I do not believe you will be able to achieve anything close to "habitable" 30 day, two person living with any configuration, just being realistic here, this is really in the pre-historic range.  Your going to get a bunch of stories I'm sure about "we did this or that" but can you really live like that?  Not wanting to start any fire-storms here, but 30 days is outside of the scope of "self contained" unless we are talking about after the nuke goes off.

 

[Gary RV_Wizard]

We use about 100 gal of fresh water per week for the two of us, and that includes a load of wash. Still need want clean "tighty whities" once in awhile! We can stretch that out a bit with some extra conserving and still not feel like our lifestyle is being cramped. Likewise, we get about 10 days on our 60 gallon black tank with some caution. I would guess you could get by on 300 gal of fresh water for a month if you worked at it.

You can do all kinds of conservation things - it's a matter of lifestyle and priorities. I'd rather get more water and dump tanks every 2 weeks than live minimally for 4 weeks, but that's my choice.

 

[GKman]

Couple of things came to mind.
An outdoor shower with a small wood pallet to stand on.
Camp where you can "water the flowers" with your gray water.
Keep a wash pan on a table just outside the door.  You'd be surprised how handy it is and how much water it saves.
Was near Moab and some kind of hunting season was starting.  Some serious looking groups without campers were towing trailers with pallet tanks full of water off to the boonies.  It's a 4'x4'x4' metal cage with a plastic tank inside.  Sure they can be found surplus somewhere.  If I really needed to move that much water, I'd rather have it on a utility trailer like they did.

 

[Betty Brewer]

We  ( 2 of us no pets) have a 100 gallon fresh water tank.  We have a 10 gallon hot water heater.  Gray tank= 67 gallons, black tank= 67 gallons for 134 total capacity.  We  have gone as long as 21 days without a fill up or dump.  All conservation methods you named were implemented.  Navy showers alternate days. Paper goods, dish washing once weekly.  Oh how I longed for a long hot shower near the end. 
It is doable however I could not sustain it for  month after month as it is such a lifestyle adjustment.  Just one city girl story. 

Betty

 

[baadpuppy]

whew... where to begin...

Tanks will be set lateral to the bus, so the weight will be distributed evenly from side to side.  All tanks will also be set between the front and rear axle.  This is a rear engine bus.  I will need to be careful not to overload the front axle, but the back axle has plenty of capacity.

The largest tank I could fit in a 24" x 18" x 84" space would be 157 gallons.  Now, the actual interior side to side spacing is 96" so I could tweak it up a bit to fit a 160 gallon tank, and still leave room for plumbing.

I intend for each tank to sit in a "saddle" that helps to reinforce it for movement side to side or front to back.  This would be a sealed saddle, so if a tank starts leaking all the spillage is contained within that saddle.  Moisture sensors will alert me to any leakage prior to it getting to an exit point.

Definitely would be a multiple tank setup.  Blank tank I intend to have a small 30ish gallon tank and when it gets about half full macerate that into the main black tank.  A combination of rid-x and sufficient water for it all to be happy should promote good bacterial action.  Good venting should help with the odor issue.  The toilet would only be attached to a tank that would be "dumped" frequently in this scenario.

Most washing would mostly occur outside I believe.  This would of course depend on what the law in that area allows.  A dish pan for washing dishes outside would also make a lot of sense.

We truly plan to live outside the bus as much as possible.  Generally, in a 30 day span of time, the activities I see us doing involve relaxing, reading, riding 4 wheelers, hiking, fishing (where allowed/desired), swimming, watching tv, writing, teleworking, and messing around on the internet.  I know many would go stir crazy in this situation, but we have many hermit-like tendencies.

30 days is a maximum design goal.  We don't expect to be doing 30 day stints often.  If we find a place that is just too wonderful to leave before 30 days, I'd like the option to stay longer.  Most likely we will do 2 weeks at a time (mostly BLM type sites).  If the bus has to be fired up to move, of course a dump station and water refill would be on the agenda.

As for food, there will be two smallish chest freezers, as well as a full upright fridge/freezer.  There's also the possibility of fishing to augment the larder.

Heat and hot water will be taken care of with a combination of solar hot water, propane water boiler, and diesel water boiler.

Electricity will be from batteries charged by solar and generator.

The range will be an apartment size propane range.  There will be several (4 to 8) BBQ style propane bottles.  An outside cooktop will also be used.  Additionally, there will be a microwave/convection oven.

Clothes washing will most likely be done with a manual washing machine.  These use very little water and soap, and provide some exercise.  Line drying is acceptable.

TV will be via satellite and anything we can get off an inexpensive antenna (for local information/weather).

Internet will be a combination of satellite and cellular.

There will be a "run to town if needed" vehicle available, and if we had to we could use it to transport liquids out and back in.  But I'd prefer not to have to do that.

The beauty of living on wheels is that if we get low on resources for some reason, we can always crank up and head for more resources.

Water filtration/purification is definitely on the wish list.  However, some places don't have much water.

Shower water could theoretically be filtered and reused.  Multiple grey tanks makes this easier.

The use of disposable dishes will keep the amount of food particles going into the grey tank to a minimum. 

utahclaimjumper and Betty, that sounds a bit more like what I was thinking when I started this thread.  If 100 gallons will "sustain" 2 individuals for 3 weeks, then 300 gallons should permit 2 individuals to make it 4 weeks with a long shower or even perhaps a hot bath once a week.

Thanks everyone for the input so far.  It is giving us much to think about.
jim

 

[34footer]

  It is giving us much to think about.
jim

Me too....my DW would go bonkers! I would have to move around every ten days max.
J

 

[tvman44]

I don't think it is possible to 30 days without emptying.  The only thing I can tell you is our 32' 5er has 3 40 gallon tanks for waste and there is no way we could last 30 days without emptying.

 

[John From Detroit]

The waste tanks on my rig are 36 gallon.. One gray tank serves the galley and front lav, the other the rear full bath (Shower, 2 lavs) the black tank serves both toilets, in water conservation mode we do not use the electric toilet (it uses way more water than the sea-land type)

We once went 8 days.. However as much as possible we used regular toilets, (Moose lodge, store, truck stop and the like) instead of our own tank.  Paper plates, and so on.

Normally we dump 2x a week.  Last week I did 3 dumps but.. Well, special situtation.

Fresh water on this house is 80 gallons, and that we top off usually 3x a week when hooked to full service, 2x when not.

That is 2 people.. We'd use a bit less water if I did the dishes instead of my wife but hey.. Only  few gallons.

 

[ArdraF]

We truly plan to live outside the bus as much as possible.  Generally, in a 30 day span of time, the activities I see us doing involve relaxing, reading, riding 4 wheelers, hiking, fishing (where allowed/desired), swimming, watching tv, writing, teleworking, and messing around on the internet.  I know many would go stir crazy in this situation, but we have many hermit-like tendencies.

The one fly I see in your ointment is - what are you going to do if it rains every day for three weeks?  That would put a serious crimp in your planning to live outside!  It's really not fun to cook outside in the rain so you need to have a good indoor backup plan.

We have 120 gallons of fuel, 100 gallons of fresh water, 60 gallons of gray water, and 40 gallons of black water.  About the most boondocking we do without too much inconvenience is ten days.  We do all the things mentioned above when stretching resources, e.g. paper plates, navy showers every other day, not flushing the toilet with every use, letting dirty dishes stack up until we run out of something like spoons, etc.  I NEED to wash my long hair at least once a week and that takes enough water that we go for hookups to do that.  Besides the diesel engine, we use the diesel fuel tank for the Aqua Hot (heating and hot water) and the generator.  We also have a 50-gallon propane tank with 40 usable gallons for the range and oven.  The convection/microwave and air conditioners need the generator to work.  I suggest a propane oven because only a range and microwave won't make for a very usable kitchen which you will need in the boonies.  It's one thing to have a minimal kitchen and be at an RV resort in a semi-urban setting with restaurants nearby, but it's quite another to be out in the middle of nowhere with the nearest restaurant 30 miles away!  You will need decent cooking facilities.  Finally, solar panels will help with trickle charging your batteries.

I hope the lady in your life is truly onboard with this idea because what you've outlined is REALLY spartan!  Personally, I wouldn't want to go 30 days without hookups.  Even the 21 days Betty mentioned is probably beyond my tolerance.  I DO like my little luxuries, and washing my hair is one of them!  I see people camped out in the desert near Quartzsite with their windmills for generating electricity, a whole bank of solar panels to charge their batteries, big "Blue Boys" to take their waste to the dump, water tanks on their pickup trucks, and so forth.  That's beyond what I would like to do more than once.  But they are pretty much off the grid.

ArdraF

 

[Wendy]

We have fresh water 75 gallons, 36 gal grey water, 46 gal black water. We can easily go 10 days. Navy showers every 3 or 4 days, baby wipes other days, hair washing (if I can't stand it) in the sink using at most 1/2 gal water, toss the water on the nearest thirsty plant. Fix meals that use less water, single-pot meals, stay away from pasta which uses a lot of water. When you run the hot water faucet, fill a gallon jug with the run-off while waiting for the hot water to come out. Use that for cooking or for flushing. Unlike most others, we typically fill up the black tank before filling the grey tank - we drink a lot of diet Coke . If you're parked anywhere near a restroom, you can significantly extend your time without filling / dumping.

Wendy

 

[Utclmjmpr]

To round out the rest of the story,, the LP tank was 68 Gal., diesel 165 Gal., 12.5 KW diesel genset when needed,. dual 43K btu furnaces, topped up ready to go 25400LBs.. >>>Dan

 

[Lou Schneider]

The largest tank I could fit in a 24" x 18" x 84" space would be 157 gallons.  Now, the actual interior side to side spacing is 96" so I could tweak it up a bit to fit a 160 gallon tank, and still leave room for plumbing.

At 8 1/2 lbs per gallon, that's 1360 lbs. of water.  You say the bus can handle that, but what happens when you have less than a full tank?  Fresh water tanks aren't baffled - there's nothing to keep the water from sloshing from side to side.  A full tank won't slosh - there's no room for the water to move.  And when the tank's empty there's no weight to worry about.  But the worst case is transporting 1/2 tank of water - that's 680 lbs of weight that's free to slosh from one side of the bus to the other.

Do the same computations for your grey and black water tanks and you may wind up with some serious weight shift - especially if the water can build up momentum across the full width of the bus.  Not what I'd want to worry about while driving down a twisty road.

 

[baadpuppy]

Lou, you make a great point.  For anything over a 30ish gallon tank, I would insist on a baffled tank.  Yes, I have concerns about baffles vs "objects", but I think it will be better to have the baffles and risk things getting trapped than to have so much weight shifting around.

For the sizes I have, I believe a custom manufactured tank is going to be required.  Several of the manufacturers I'm looking at provide baffling as an option in their tanks.

The really good tanks I've looked at are aluminum, made for marine use, available in custom shapes and sizes, and are properly baffled for the various types of movement a boat would experience.  However, they're also expensive, and it would take me time to get enough of those for 30 days stay.

I think I'm going to use 4 gallons per adult per day as my general rule of thumb.  If I use less, great.  If I use more, I'll just have to adjust the boondocking time.

I also think if I keep a separate set of tanks just for the showering, and make use of really good filtration and purification, I could re-use the shower water for more showers.  It depends on how good the filtration and purification process works, and how expensive that process is in terms of consumables and energy consumption.  This would seriously cut down on the amount of water that would be needed and consumed.  On the other hand, there's a bit of an ick factor involved.  The same shower water once recycled could be used to help flush the toilet.

Much more to think about...

thanks,
jim