Effects of lake or stream water sources on expedition RV's water systems

[tommesch]

Hi everyone,

I'm a noob here and need some advice. I'm looking into an expedition RV. After about 40,000 miles on the ocean (coastal) and all the challenges associated with that, I'm really liking the Earthcruiser...exactly why is a totally different thread.

The filtering system on the Earthcruiser is just what i'm looking for. Its rated for about 4000 gallons of pure water before a filter change...quite handy. Being that, that is for drinking and cooking only....not going to use that water for shower, dishes, and laundry. The filtering system will make that water drinkable, but how does that unfiltered water, when pumped into the tanks, effect the cleanliness of the tanks over time? Will the laundry become dingy and gray?? Will i loose the allure of my glorious hair?

There have been many times in Northern California that i've jumped in a lake that has been...we'll say, less than crystal clear, and had a blast doing it. Not afraid to take a bath in a lake with the right soap....or without.

What i'd like to know is more about is filling the tanks with water from lakes, streams or wherever, and the consequences associated with unpurified water in the system.

I'm fine with cleaning out the system every now and then. I just want to know what to expect.

Thoughts?

Comments?

Thanks everyone!

Tom

 

[blackduck]

set yourself up a filter for filling the tanks
available at any caravan (read trailer) parts shop
get one that can be reversed to clean the membrane
filter it through 5 micron going in
let the onboard system do the rest

been doing it for years - never a problem

 

[gait]

haven't a clue exactly what Earthcruiser has ... I have a diy build. Here's a mix of theory and practice.

I prefer flowing water to still. Oxygen in water is good. I add chlorine (household bleach or sodium hypochlorite pellets) while filling. If I can smell the chlorine there's free chlorine present then I'm happy. A couple of capfuls per 100 litres. I filter drinking water through 10 micron sediment filter then 1 or 0.5 silver impregnated activated carbon filter.

Theory is - the chlorine kills most things except protozoa like amoeba, giardia and cryptosporidium that form cysts, but the cysts are too large to pass through the second small filter. Chlorine kills bilharzia (schistosomiasis) - not yet a problem in US.

A problem with filters is that they concentrate things. The silver and the free chlorine help stop things growing in the filters. The activated carbon also remove the chlorine. Time to replace filters if chlorine taste in drinking water.

Alum is a flocculant which can be used to drop sediment out of water - add in a bucket and wait for sediment to sink. I've never needed it as I always seem to find enough clear water.

No issues with tank residue or water caused illness after 35+ countries.

I suspect some build up of carbonate scale in the calorifier, hot water seems to take longer to heat after 3 years continuous use. I've yet to inspect. The small (1mm+) holes for flushing water round the rim of our vacuum loo became blocked with scale, there must be some evaporation (like stalactites) but easily unblocked. A bit of scale build up on end of drinking water and sink taps. Shower rose surprisingly free - we should have washed more often. Vacuum loo cassette ok. Grey water tank ok.

Limited ways of knowing about the unseen water pollution like heavy metals. We were on the move. We became more particular if in one place for a period. A general check of insects and frogs around the water can be useful. The more life the healthier the water. I've seen descriptions of increasingly sensitive insects but I'm not that good a biologist.

Not sure about the laundry question. The Indians (in India) seem to get laundry clean with water I wouldn't swim in. My experience is laundry is as much about technique as water. We did our laundry in buckets by hand.

There are many views on water treatment for RVs. The above seemed logical for me. The most common addition to the above is to filter on the way into the tank. A simple cloth filter was enough to keep seeds and insects out. There's also various water treatments beyond chlorine - solar stills, UV, oxygen, etc.

I recently shock treated all tanks with large volume of chlorine prior to return to Aus. Rubber seals, pumps and pipework so far so good. My tanks are food grade polypropylene.

 

[Joe917]

I run all suspect water through an inline sediment canister filter on the hose before it enters the tank.
after the tank and before the pump 2 canisters, a 1 micron sediment then a carbon block.
I also sterilize the tank with a heavy dose of chlorine as required.
Lots of good info here : http://www.rvwaterfilterstore.com/ABChoosingASystem.htm

 

[dlh62c]

Let's say the filter is sorted out. You have to get the water into the tank, would the perferred method be a pump that pushs or pulls the water though the filter?

 

[whatcharterboat]

Let's say the filter is sorted out. You have to get the water into the tank, would the perferred method be a pump that pushs or pulls the water though the filter?

Hi Daryl,

Strainer before the pump. Filter after.

Having an on board transfer pump is cool but most pumps will struggle to lift more than a meter or two from a dry lift (without any priming) so placing a filter before the pump will restrict this even more. You should always have a strainer before a pump to ensure no debris is going to block the valves (diaphragm pump).

Some of our customers carry a portable pump in preference to an "on-board" pump. A little more hassle but you have the ability to pump up from a lower water source like a dam or in creek that's down off the road. Actually one guy we built a truck for carries a tiny portable two stroke fire fighting pump. He carries two stroke fuel anyway for his chainsaw.

My boss carries a tiny submersible pump (like a bilge pimp) with an inline filter......the power is plugged into a rear locker and he can drop it into a creek, well, bucket under a rainwater tank or even drop it into the 18 litre springwater bottles we use on the drink coolers around our factory.

Hope this gives you some ideas.

Kind regards
John.

 

[tommesch]

Thanks to everyone that has contributed to this thread.

gait, that was a ton of information. Thanks for that.

What i'm gathering is:
1. when pulling water out of a stagnant swamp (worst case scenario) use a particulate filter and add chlorine until you can barely smell it. Thats good enough for showers and laundry.
2. The purifying system (same as on a 747) will remove the chlorine for optimal drinking / cooking water.
3. Shock the system with bleach every couple years.

Correct? Please correct me if i'm off on this.

Thanks again everyone!

-Tom

 

[blackduck]

Daryl
simple solution
get yourself a motorhome water pump with a decent gallons / hour rate
mount it in a small fishing tackle box with garden hose fittings on the suction and discharge
add an in line fuse and switch

for the suction side rig a hard pick up into a swimming pool floating chlorine dispenser (you may have to weight it down a tad to get it to sit upright)
make it so the water is drawn about 3' under the surface, the basket of the dispenser will act as the coarse strainer
for the discharge hose an in line cleanable filter will do ( i use a 5 micron)
and there you have it the ability to draw water from any water source

match that to the filtration system in your truck and add a couple of chlorination tabs if need be

 

[gait]

Thanks to everyone that has contributed to this thread.

gait, that was a ton of information. Thanks for that.

What i'm gathering is:
1. when pulling water out of a stagnant swamp (worst case scenario) use a particulate filter and add chlorine until you can barely smell it. Thats good enough for showers and laundry.
2. The purifying system (same as on a 747) will remove the chlorine for optimal drinking / cooking water.
3. Shock the system with bleach every couple years.

Correct? Please correct me if i'm off on this.

Thanks again everyone!

-Tom

that's basically it. IMHO the chlorine does most of the work. It reacts with "stuff" in the water and is consumed. How much varies significantly. Smelling the free chlorine means there's some left over to kill "things".

We didn't resort to bottled drinking water as some independent travelers do. We could probably fill a book on whether its a fashion item in the developed world or an essential item in less developed. FWIW the tap water at home has taken some getting used to again (after 3 years of travel).

A lot depends on geography and temperature. Also travel pattern - there's a difference between moving most days and sitting in one place for a period. If nothing else setup is different. We use buckets to carry water from lake or creek or roof to truck then pump from bucket. Many times we couldn't get truck close enough to pump directly. Worst case was a 30ft hike up a steep bank Even a hotel car park can be a problem for a hose if there are parked cars in the way. Oz seems relatively easy for water and waste disposal in comparison to a lot of other countries. Even the "developed" countries differ considerably eg don't take water from a fuel station in Thailand its possibly poorly recycled.

 

[mog]

John has a very nice description of his system for 'washing' his Fuso HERE
The external pickup/pump/filters can surely be use for a 'potable water' system with later filtration / purification.

 

[westyss]

Just wanted to jump in here with a simple recommendation to top up other good information that is already here, and that is if using a pump to draw water from a source to use a 110 volt pump instead of a 12 volt unit.

If you think about it those small pumps may have decent GPM in normal conditions but typically one cant get very close to the water source and will need to also raise the water high enough to fill a tank which will increase the work load on a relatively weak pump, the wiring for the 12 v pump will need to have the ability to be extended if one cant get very close to the water source and in 12 volts will have a greater voltage drop unless heavier wire is used. By using a 110volt or 240 volt pump you will not only have more power to raise the water up higher but you will also be able to use a cheap extension cord and have very little voltage drop in comparison.

Along with voltage drop, weak pump,and lifting the water with a 12 v pump if you stick an inline filter in there too that will just kill the GPM's

Most rigs I have seen have power inverters and besides they are so cheap now there is no reason not to have one or two onboard.

I use a sump pump I bought on sale, always have several extension cords with me. I put the pump into a shallow wash basin with water flowing over the lip so as not to pick up any sand or gunk and run a house filter on that line just prior to the tank. Then like others use chlorine or bleach in the tank and have a dedicated two stage filter for drinking water. My master plan was to have two additional water tanks between the frame rails for "not very desirable looking water" that can be used for showers, dishes etc and keep relatively clean water in a main tank, that seems like a fairly common thing to do.

John Rhetts did a great write up on it and the only change to his design would be the pump used. I guess I should also point out that my sump pump has an impressively high GPM, when I first tried it out I tested it in a five gallon bucket and it drained it in about five seconds!

 

[JRhetts]

I am sure Ives' 5gal-in-5sec pump is a winner! I did not even think about going to AC, even tho I do have an inverter – tunnel vision.

I will simply report that at the end of 50 feet of 5/8" garden hose and 50 feet of 12 ga extension cord, my 12v pump pushes water up at least 15-20 feet of rise and through my sediment and .1micron filter at a quite acceptable rate to fill my 105 gal of potable water tanks.

I am sure, however, that mud would fly off the rig with Ives' pump! Mine washes it off, and the brush-on-a-wand finishes the job, but at a more sedate rate to be sure.

If you will permit me, I will make a comment about adding chlorine to drinking water. Over the past 10 years I rarely have added chlorine to my drinking water; I have been able to find water that others are drinking on a regular basis and I have taken the chance to use it as well. On the other hand, I do de-bug my tanks and plumbing if I have not been using the rig actively for a couple of months or more. Based on research I did, and a seemingly excellent article in Overland Journal a number of years ago, I harbor the impression that we tend to use a WHOLE LOT MORE bleach than we need to and from what I can tell extra chlorine is not a good thing. I now use the following table to dose my tanks when I do it [probably way less chlorine than you may be accustomed to using, but this is what math and science say is needed to neutralized a potential organic load and not leave a whole lot of 'free' chlorine ions floating around for your body to ingest]:



John

 

[biggoolies]

sump pump

Yves, What is the amperage of your sump pump in 12volt terms? It looks like some of them can burn up to 75 amp hours. But of course the post is about supplying water to your tanks not washing the truck I suppose.

Just wanted to jump in here with a simple recommendation to top up other good information that is already here, and that is if using a pump to draw water from a source to use a 110 volt pump instead of a 12 volt unit.

If you think about it those small pumps may have decent GPM in normal conditions but typically one cant get very close to the water source and will need to also raise the water high enough to fill a tank which will increase the work load on a relatively weak pump, the wiring for the 12 v pump will need to have the ability to be extended if one cant get very close to the water source and in 12 volts will have a greater voltage drop unless heavier wire is used. By using a 110volt or 240 volt pump you will not only have more power to raise the water up higher but you will also be able to use a cheap extension cord and have very little voltage drop in comparison.

Along with voltage drop, weak pump,and lifting the water with a 12 v pump if you stick an inline filter in there too that will just kill the GPM's

Most rigs I have seen have power inverters and besides they are so cheap now there is no reason not to have one or two onboard.

I use a sump pump I bought on sale, always have several extension cords with me. I put the pump into a shallow wash basin with water flowing over the lip so as not to pick up any sand or gunk and run a house filter on that line just prior to the tank. Then like others use chlorine or bleach in the tank and have a dedicated two stage filter for drinking water. My master plan was to have two additional water tanks between the frame rails for "not very desirable looking water" that can be used for showers, dishes etc and keep relatively clean water in a main tank, that seems like a fairly common thing to do.

John Rhetts did a great write up on it and the only change to his design would be the pump used. I guess I should also point out that my sump pump has an impressively high GPM, when I first tried it out I tested it in a five gallon bucket and it drained it in about five seconds!

 

[westyss]

Yves, What is the amperage of your sump pump in 12volt terms? It looks like some of them can burn up to 75 amp hours. But of course the post is about supplying water to your tanks not washing the truck I suppose.

Lets see if I get this right........... 2.2 amp at 115v will be 21 amps at 12v plus whatever the inverter uses.


John, How are you?
Really the only reason I went with a 115v pump was because I was cheap and didn't want to pay the crazy price for a 12 volt pump in the GPM needed, I got the pump on sale and is easily replaced.
Also I did not time the emptying of the five gallons but guessed at it as I was a bit shocked at how fast it was emptying and had to run and unplug it, math is not my strong suit but here goes: says 1500 gph on the pump. devide by 60=25 25/60 again = .41 per sec .... if thats right then 5 gals in 12 seconds.??

I also agree with limiting the amount of chlorine, or bleach, I usually err on the "less" side, using around 1 tablespoon for 70 gallons or around there, not very accurate science there, I like to have a slight smell of bleach in the tank but no smell from the drinking water tap.

 

[gait]

we're about on par with the chlorine. Some of it gets consumed oxidising inorganic micro-pollutants, some the organic micro-pollutants, and the remaining free chlorine kills things and keeps them dead. Its the free chlorine we can smell in the water - just enough to smell is my test.

The free chlorine has a half life - about 2 hours. Sunlight reduces that but our tanks are dark.

Filtering out the free chlorine for drinking is a good idea - though the activated carbon filter adsorbs rather than physically filters the chemicals and physically stops the dead things. Adsorbtion also removes some of the oxidation products of the chlorine reaction with organic micropollutants. Some of those products are carcinogenic - which is probably why ozone is used for water treatment in parts of Europe (and probably further afield).

In an ideal world we would pass the water over activated carbon to remove organic and some inorganic micro pollutants, then chlorinate, then activated carbon again to remove the excess chlorine.

My world is far from ideal. The long term risk of digestive tract cancers from chlorinated water is still being researched. The activated carbon apparently adsorbs only about half the organic oxidation products. Half of what one may ask?

I did a bit of research before traveling. While I can claim to have been water borne disease free there's no baseline to compare and I haven't a clue about the long term effects, though I'm led to believe that life is a somewhat transient affair. I've been drinking chlorinated tap water for many years so a bit more will either tip the balance or not.

I decided against carrying chlorine testing equipment (like DPD tablets that I occasionally use for my swimming pool).

The techie bits are real. I'm way short of being as worried about water treatment as the above may convey. I simply do the research and adopt the pragmatic, practical approach - less than a capful of chlorine each fill. Ever since I saw my first "keep off the grass" sign I've been prone to ask "why". Just a habit!