How to Sanitize RV Freshwater Tank & Lines (7 Easy Steps)

To keep the water in your RV “fresh” and avoid making you and your family sick, sanitizing the freshwater tank and water lines is extremely important.

In this quick guide, you’ll learn how to sanitize your RV freshwater system (tank and lines) in 7 easy steps! Plus, learn how often you should do it and what NOT to do (this is important)!

How to Sanitize Your RV Freshwater System

What You’ll Need

  • Bleach: This common household item is the main ingredient for sanitizing your RV tank. It’s a powerful disinfectant capable of killing bacteria, mold, and other harmful microorganisms that may be lurking in your water system. Ensure you use plain liquid bleach without any added fragrances or other special ingredients.
  • Water: You’ll need plenty of fresh water for this process. Water is used to dilute the bleach and to rinse the tank after the sanitization process.
  • Measuring Cup: A measuring cup is essential for ensuring you use the correct amount of bleach. Too much bleach can damage your RV’s water system, while too little may not effectively sanitize the tank.
  • Large Pitcher: A large pitcher is useful for mixing the bleach and water before adding the solution to your tank. This helps ensure the bleach is properly diluted and evenly distributed throughout the tank.
  • Rubber Gloves: To protect your skin from the bleach.
  • Funnel: To pour the bleach/water mixture into your freshwater tank.

These supplies are the backbone of your RV tank sanitization toolkit. They’re easy to find and use, making the sanitization process straightforward and manageable.

Step 1: Prepare Your Water Heater and Pump

  1. Turn Off the Water Heater: Begin by switching off your water heater. To avoid damaging the tank, make sure to run hot water from your taps for about one to two minutes. This action helps to eliminate any hot water from the system and allows the water heater to cool down before the draining process commences.
  2. Disable Your Water Pump: Also, remember to turn off your water pump. To ensure complete water drainage, open all the faucets in your RV.

Step 2: Drain the Fresh Water From the System

If your tank isn’t already empty from winterization, this step is crucial.

Locate the Drains

Find the fresh water tank drain and the low-point drains for your RV’s plumbing lines, which are typically located underneath your RV.

These drains are identifiable by red or blue drains extending out of your RV’s bottom. However, some RVs might have a different identification system, so refer to your owner’s manual if you’re unsure.

Drain the Water

Once the drains are located, open the low-point and tank drains to drain the water from your freshwater system.

Step 3: Add the Bleach Solution to Your Fresh Water Tank

As a rule of thumb, you’ll need approximately a 1/4 cup of bleach for every 15 gallons of water your fresh water tank can hold.

For example, a 45-gallon freshwater tank would need about 3/4 cup (or about 6 ounces) of bleach for sanitization.

Important: Don’t pour undiluted bleach directly into your freshwater tank. Instead, dilute the calculated amount of bleach in at least a gallon of water.

Pour this bleach mixture into the freshwater inlet on the side of your RV using a funnel.

Step 4: Fill the Tank and Circulate the Bleach Solution

Fill your tank with clean, potable water. This action will distribute the bleach solution throughout the entire tank.

Once the tank is filled, turn on your water pump and open all the faucets and the shower in your RV. Allow the bleach solution to flow through all parts of your freshwater system for a few minutes.

After this circulation, close the faucets and turn off your water pump.

Step 5: Allow the Bleach Solution to Sit

Let the bleach solution sit in your tank and plumbing lines for 12-24 hours for effective sanitization. Just don’t let it exceed 24 hours.

Step 6: Drain the Sanitized System

After the bleach solution has sat for at least 12 – 24 hours, proceed to drain the system.

Dispose of the Bleach Mixture Responsibly

For this step, ensure that you’re using appropriate disposal methods. If you’ve used bleach, it is advisable to avoid draining your tank directly into the soil, as bleach can harm plant life and degrade soil health.

The best option is to connect your gray water tank to a sewer connection and then run the bleach/water mixture through your plumbing system into this tank. Then, open the low point valve after turning off your water pump, which ensures complete drainage of your freshwater tank.

Step 7: Rinse Your System

The final step involves thoroughly rinsing your system. Fill your tank with fresh water and run it through the system, making sure to open all the faucets. Continue this flushing process until there’s no bleach odor.

If your RV comes equipped with a water filtration system, consider replacing your filters after this sanitization process. This ensures that you’ve effectively removed all sanitizing chemicals from your system, and it’s now ready for water use.

After you’ve completed the sanitization process and have replaced any filters, you are now ready to fill your RV water tank with freshwater. Don’t forget to bleed the RV water lines after filling the freshwater tank, so you’re not surprised by sputtering water later!

How to Sanitize RV Freshwater Tank Without Bleach

While cleaning your RV freshwater system with a bleach mixture is fairly easy and extremely effective, there are a few other methods you could try if you don’t like the idea of using bleach.

Sanitize RV Water Tank With Camco Spring Fresh

Camco TastePURE Spring Fresh Water System Cleaner and Deodorizer for RV and Marine (phew, that’s a mouthful!) is a product that provides a safe and easy way to sanitize your freshwater system.

It’s specially formulated to clean your tanks and lines and remove bad odors.

And it’s super simple to use:

  1. Drain the RV fresh water tank and lines, including the water heater. Be sure to close the valves once drained.
  2. Fill your freshwater tank 2/3 full of water and add Spring Fresh Cleaner. Add 1 quart for every 25 gallons of tank capacity.
  3. Turn faucets on for 2 minutes to allow the solution to fill the entire system, and allow it to sit for 10 minutes.
  4. Flush the system twice to completely remove the product.
Camco TastePURE Spring Fresh Water System Cleaner and Deodorizer

Camco TastePURE Spring Fresh Water System Cleaner and Deodorizer

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Clicking this link to make a purchase may earn us a commission at no additional cost to you.

How to Sanitize RV Freshwater System With Other Household Products

Now, let’s talk about sanitizing your freshwater system with common household products (not including bleach).

You’ll see many different articles on the internet about using various household products to clean your tank and lines.

Unfortunately, most use a certain product and assume it cleans the system. But a closer look would likely reveal that it didn’t do as well as they thought.

Luckily, Colorado State put together a nice little chart showing the effectiveness of household products in killing the big three common types of bacteria, including Listeria, E. Coli, and Salmonella. Here are the results:

Sanitizer effectiveness guide

We can take this information and apply it to sanitizing an RV freshwater system.

Sanitize RV Water Tank With Vinegar

Acetic acid (or vinegar) is effective for cleaning your freshwater tank. But that’s if the vinegar is at 130 degrees! And undiluted. White distilled vinegar, at room temperature, is only effective at killing Salmonella.

And there’s no guarantee that when you fill your RV water system with vinegar heated to 130 degrees, it will remain at that temp. It’s likely to lose a few degrees, if not much more, pretty quickly as it moves through the lines.

So, keep this in mind if you choose to go this route. And we recommend using a water test kit to ensure your water is safe to drink after using this method.

Coliform Bacteria Test Kit for Drinking Water

Coliform Bacteria Test Kit for Drinking Water

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Sanitize RV Water Tank With Hydrogen Peroxide

Slightly more effective than white vinegar is hydrogen peroxide. At room temperature, it effectively kills E. Coli and Salmonella but not Listeria. Heated to 130 degrees, it’s effective at killing all three.

Keep in mind, however, that the test was performed using undiluted hydrogen peroxide. Mixing it with water could potentially cause it to be far less effective.

Sanitize RV Water Tank With Baking Soda

Just don’t. Unfortunately, sanitizing your water system with baking soda is still common advice on blogs and forums, but it’s ineffective. And why put your health, and that of your family, in jeopardy using an inferior sanitizing technique?

If going green(er) is the main reason for ditching the bleach method, give Camco TastePure Spring Fresh a try.

Camco TastePURE Spring Fresh Water System Cleaner and Deodorizer

Camco TastePURE Spring Fresh Water System Cleaner and Deodorizer

Buy Now on Amazon

Clicking this link to make a purchase may earn us a commission at no additional cost to you.

How to Maintain a Clean RV Freshwater System

Maintaining a clean RV fresh water tank is important for both the longevity of your RV’s systems and your own health and safety. Here are some tips:

  1. Regular Sanitization: Sanitize your freshwater tank at least once or twice a year as part of your regular maintenance routine. This helps to remove any build-up of bacteria, algae, and other microorganisms. If your RV has been in storage for a while or if you’ve been traveling in areas where the water quality might be questionable, you may want to disinfect it more often.
  2. Use Clean Water Sources: Whenever possible, fill your tank with water from a trusted source. Water quality can vary greatly from place to place, so be mindful of where you’re sourcing your water.
  3. Use a Water Filter: Filtering the water that you put into your tank will help remove impurities and improve the taste of the water.
  4. Keep It Sealed: When not in use, make sure your freshwater tank is properly sealed. This helps to prevent contamination from dirt, dust, insects, and other potential contaminants.
  5. Regular Use and Emptying: Stagnant water can be a breeding ground for bacteria. If you’re not using your RV for a while, it’s better to drain the water system rather than leave water sitting in the tank.
  6. Monitor for Leaks: Regularly check your system for leaks. A leak in your freshwater system can introduce contaminants and also lead to other problems in your RV.
  7. Replace Damaged Components: Regularly inspect your freshwater system for any damaged parts, such as seals, hoses, and the tank itself. Replace any damaged parts immediately to prevent contamination.


Is It Necessary to Sanitize the Fresh Water Tank in an RV?

If you use the fresh water in your RV to drink, wash dishes, and shower, then yes, it is necessary to sanitize the fresh water tank. Over time, bacteria, algae, and other microorganisms can build up in the tank and the plumbing system. This can lead to bad smells, unpleasant tastes, and in some cases, could potentially cause health problems. Proper sanitization helps ensure the health and safety of those using the water.

How Often Should I Sanitize My RV Water Tank?

Typically, we recommend you sanitize your RVs freshwater system after pulling it out of storage as part of the camper de-winterization process. If you live in your RV full-time, then every six months is a good schedule to set.

But remember, if you notice that the water tastes a bit strange or has a foul odor, it’s time to sanitize the tanks immediately. In other words, don’t wait around for the scheduled sanitization.

Tip: Keep your freshwater system cleaner for longer by only adding filtered water to your tank with the Camco TastePure RV Water Filter. And be sure to flush your water system if the water in your tank is over two weeks old. Learn more in our guide on How Long To keep Freshwater In An RV Tank.

How Long Does It Take To Sanitize an RV Fresh Water Tank?

Sanitizing an RV freshwater tank is a multi-step process that takes time to complete properly. The actual working time, which includes preparation, draining, filling, and flushing the system, might be around 1-2 hours. However, the majority of the time is taken up by the sanitation process itself, where you need to let the bleach solution sit in the tank and lines for between 12 to 24 hours.

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4 thoughts on “How to Sanitize RV Freshwater Tank & Lines (7 Easy Steps)”

  1. Thanks for the tips. I have the Camco product and it does a good job just as you mentioned. Learning more and more about my rig everyday and adventure. Thanks again!

  2. Can you sanitize the system without filling the fresh water tank? We do not dry camp or boon-dock, we honestly have no intentions of ever camping without a water connection. Is there anyway to sanitize the system without filling the fresh water tank?

    • Yep, use the winterizing port if you have one or simply pour bleach into the water hose and then connect it to the city port.


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