How To Keep RV Water Fresh: The Ultimate Guide

As an Amazon Associate I earn from qualifying purchases. Click here to read more

Table of Contents

One of the big differences between an RV and a home is where the water goes, and how it is stored. RVs, of course, have their three tanks. The white, or freshwater tank, the grey, where water from the sink and shower drains to, and the black, where toilet waste is flushed. 

These tanks have to be emptied and cleaned regularly to maintain them. You’ll need to watch their fill valves and ensure that they’re not overflowing. What most RV owners are worried about in regards to their tanks, however, is the presence of smells. 

Nothing will sour your mood quite like sour smells, especially ones leaking from places you’d associate with cleanliness. The sink and shower shouldn’t have an stale, or at worse offensive, odor to them. So, how do you keep your RV water fresh? 

Sanitizing your tanks, keeping food out of the drain, and giving the tanks a good cleaning are great ways to keep the tanks fresh. Your black water tank especially will benefit from cleaning and sanitizing. You can stave away odors with baking soda, or even with orange pop. 

How To Keep RV Water Fresh

There are a few ways you can keep your RV water fresh, clean, and free from odors. It’s essential to tackle small stinks before they get worse- because they’ll usually only get worse as more material drains to the tank. 

Sanitize Your Fresh Water Tank 

Even your fresh water tank might need a hand in living up to its namesake. 

Older fresh water tanks can sometimes develop a sheen of bacteria on the inside. It’s prone to happen with old age, or with low use. If you’ve kept the RV unused for the winter and plan to break it out for summer vacation, take time to sanitize it. 

This process will likely take at least a day or two, since you need to leave the water to sit for several hours. Be sure to give yourself plenty of time to sanitize the white tank.  

How To Sanitize Your Freshwater Tank  

  1. Create a mixture of water and bleach that corresponds to the size of your tank. On average, a 40 gallon tank will need four gallons of water with one cup of bleach. Scale up from there: 1 ½ cups and six gallons for a 60 gallon tank, eight gallons and two cups of bleach for 100 gallon tanks, ect. 
  2. Add the bleach mixture to the tank, and then fill it the rest of the way with fresh water. 
  3. Run your sinks, faucets, and showers one by one. You should keep running them until you can smell the bleach through each faucet. Keep this up until the tank is completely emptied. 
  4. Refill the empty tank and let it sit overnight. 
  5. Repeat step 3 as much as needed until you can’t smell the bleach anymore. 

After that, your tank will have been thoroughly cleaned, and all of the bleach safely washed away and removed. You’ll be able to notice the difference if you’d been drinking and washing with old, dirtier water. 

Keep Food Out Of The Drain

When you’re washing the dishes from your family’s dinner, make sure the plates and bowls are completely scraped clean before you start washing them in the sink. Once you’re sure it’s mostly clean, you can properly wash it off in the sink. It’s impossible to not let anything go down the drain, but this will help keep odors from accumulating. 

For added safety, you can also use a mesh strainer basket to catch any errant bits of food. Pieces that were stubbornly stuck on when you tried to scrape it off will get washed away with water and caught in the strainer. This is going to prolong the freshness of your grey tank considerably. 

Clean Out The Black Tank 

For obvious reasons, the tank that takes all of the sewage is going to be the most prone to causing odors. It will benefit from a proper cleaning, especially if you do so every time you are at a dump station. 

When you have dumped out the tank, stick a garden hose into the hole of your toilet. Most RV’s have their black tanks directly under the toilet to prevent having long, clog-prone tubes to worry about. 

Turn the water on from the hose and move the nozzle about, letting the spray hit every nook and cranny of the black tank. The pressure from the hose will do a good job of loosening anything that might be stuck on. 

When the tank is full to capacity, empty it again. If you’re satisfied that the tank is clean, you can call it good there. If not, try this a few more times. 


There are some chemical treatments that are intended just for cleaning out your black tank. They are usually at hardware or specialty RV stores. You can also make your own at home using a few common cleaning products. 

Keep The Black Tank Valve Closed 

Speaking of the black tank, you should aim to keep the valve closed. This might seem obvious, but if you’re connected to a campsite for your plumbing, leaving it open is tempting. 

Leaving the black tank open means that liquid waste will drain from the tank, but solids won’t. Eventually, those unspeakable solids will start to build up, making for a cleaning job no one wants to do. That buildup will, as expected, smell terrible. 

Always keep your black tank valve shut tightly unless you need to open it up for a connection. 

Clear Out The Smells 

If you don’t have the time to undergo a full deep clean on your tanks, you can still fend away foul odors in a pinch. 

Baking soda is a popular choice for litter boxes and refrigerators alike for good reason: it will soak up a smell like a champ. When you’re done doing your dishes, put a spoonful of baking soda into the kitchen sink. Wash it away with water. It’s a small preventative measure that can keep odors from building up quickly. 

Try adding some baking soda every time you dump the grey water tank too. Rinse it with hot water, and you’re building up a defence against more stinks developing down the line. 

Soda in the liquid sense can lend a hand at deodorizing your tanks too. Orange soda, when poured down the drain of your sink or shower, can also cover up and eliminate some smells. The fizz in the soda will clear away any offending sludges, and the fresh orange scent will keep the water fresh. 


Cleaning out all of your tanks before a big trip? One trick that can help ease the process is taking the RV for a drive after filling the tank with a hose. The vibration from being on the road will shake loose any debris or scum that might be clinging on. 


As tanks age and endure more use, they’re going to inevitably start feeling not so fresh. If you maintain them and clean them often, though, you can easily refresh them. 

Regular sanitation will help keep everything above board in terms of keeping odors away. You can also freshen up the grey water tank with baking soda or orange soda. Cleaning out your black water tank every time you empty it will do wonders for maintaining freshness. 

Scroll to Top