Monday, December 4, 2023


Ask Dave: What filtration system do you recommend to fill freshwater tank when boondocking?

Dave Solberg is a leading expert in the RV industry and author of the “RV Handbook” as well as the Managing Editor of the RV Repair Club. Today he discusses water filtration systems for use while boondocking.

Dear Dave,
I will be traveling in a brand-new 24′ Class C Conquest RV with a 48-gallon freshwater tank. I would like a water purification system that has at least a garden hose input attachment for filling. My thought is to rinse out then fill up the fresh water tank from home every time I start out. I plan on being out for 6 months, come home, and camp locally during the summer months.
I’ll be camping in the brush and be dependent on river or lake water to refill the freshwater tank most of the time. So I’ll be using some type of electrical water pump with an output garden hose connection. I already know at least two rivers will have arsenic, lead, and mercury.

Can you recommend a system to use and what all I’ll need to implement it? This system will be installed permanently into the RV and will be used for all seasons so it will have to be a heated area and be drainable after use. —Randall

Dear Randall,
There are several methods and products to not only filter your water but to purify it as well. The National Park Service has a great website that I have sent boondockers to for several years here.

It is always a good idea to do a little research on the region you are planning to visit, as well, as there may be sites that you can replenish your water source close by with a well system that has been certified pure and posts a Safety Data Sheet (SDS; formerly Material Safety Data Sheet, or MSDS). Or, it may tell you if there are certain areas that have known water purity issues and have posted alerts.

In our area, we have a recreational lake that oftentimes gets a spike in algal (or algae) bloom. This is typically not deadly, but can cause irritation. However, they can be harmful to pets. You can also encounter harmful algal bloom in remote areas, as well, and it’s not advised to drink this water.

There are two steps needed when getting water from a river or lake ready to drink: filtering and purifying.

Water filtration systems

It is recommended to use a filter that has a pore size of less than or equal to 1 micron. Most of these will filter out sediment such as lime, rust, and calcium, but typically do very little for minerals, arsenic, and bacteria.

A residential filter such as this will only filter at about 3 microns and does mostly sediment. Water softeners will reduce calcium and magnesium, but do not affect bacteria or arsenic.

Boiling your water is the best way to kill bacteria and parasites, but is typically not a practical option if you are looking to use more than just a small amount. For 6 months it might not be something you want to do every day.

There are chemical products such as chemical tablets or liquid drops that use iodine and chlorine dioxide. I would keep them handy just in case of an emergency.

There are several reverse osmosis and UV products on the market. One of the best for boondocking that I have found is from Clearsource, with either the Ultra or the Nomad.

The Ultra is designed to work with your onboard water pump and comes with a three-stage filter that has a 5 micron initial filter for larger sediment, a 0.5 micron second filter to reduce chlorine and volatile organic compounds and contaminants, then the VirusGuard that reduces bacteria.

The Nomad has a similar 3-stage filtration. However, it comes in a handy package with its own water pump to take down to the water source and draw from the river or lake. This might be the system that would work best for your needs, but it is a little higher priced.

You can find these systems or customize your own here or on Amazon.

I know there are several models of water filtration systems available, so I welcome our readers to log in and tell us about what works best for you.

Read more from Dave here


Water filtration: Keep it clean, keep it safe


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Dave Solberg
Dave Solberg
Dave Solberg is a leading expert in the RV industry and author of the “RV Handbook” as well as the Managing Editor of the RV Repair Club. He has been in the RV Industry since 1983 and conducts over 15 seminars at RV shows throughout the country.



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Bob Weinfurt (@guest_155616)
1 year ago

Why use water you know is contaminated? I’d buy my drinking and personal use water, from the store and use the contaminated water just for flushing the toilet. Yea, it creates extra work and weight but it’s the best way to stay away from the dangerous contaminates.

John McMann (@guest_155606)
1 year ago

Any way to prevent coliform bacteria in your water?

Steve Hericks (@guest_155571)
1 year ago

A common misconception with RO systems is they ‘waste water’, which is true if you try to install a system designed for ‘residential’ use in an RV. Residential systems are designed with the expectation that 1) the source water is plentiful, 2) service pressure is high and 3) a sanitary drain always available. RV’s obviously do not have these. It is relatively easy to modify a residential RO design to work in an RV by 1) directing ‘bypass water’ back to the fresh tank. Bypass water has a slightly higher level of contamination but most water is used for cleaning so is not harmful. 2) install a ‘permeate pump’ which is a water pressure-driven pump that improves the efficiency of the RO system and compensates for low water pressure.

Steve Hericks (@guest_155569)
1 year ago

Its pretty hard to make a single recommendation on filtration when there is such a wide range of contaminants and an equally wide range of devices to remove those contaminants. As an engineer, before designing something (or buying something to perform a purpose) the first and most important question is ‘what do you want to achieve?’ This requires the user actually understand water purity issues. Secondary to that is what are the conditions (source contamination most of all). This is a really open-ended question and impossible to answer without asking those questions first. Some filtration precepts to understand; 1) no filter is 100% effective. They always pass some quantity of contamination. 2) Removing the chlorine/chloramine in the water before you put it it your tank may allow that small percentage of biologicals passed to grow rapidly by the time you use the water. 3) The biggest contaminants are easiest to remove but the least consequential.

Thomas D (@guest_155564)
1 year ago

Postscript: ro filters waste more water than they produce.
3 to five gallons to get one good one!

Thomas D (@guest_155563)
1 year ago

I wouldn’t do what you propose. I’ve been in parks where water was unsafe. And you want to take it out of the lake. Write your last will and testament now.
An RO system might work but putting in all the contaminants you’d be changing filters all the tine. My household ro uses 3 filters that cost around $100 a pop. Better you buy some sort of bladder and go get known quality water, or break camp and go get it.

Bob p (@guest_155497)
1 year ago

If you want to camp like that you should join the Marines, I had all that type camping I wanted in 7 1/2 years. Lol

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