How Long will a Black Water Tank last in a RV?


When we go camping, there is always the question of will we need to move the RV to dump tanks in the middle of our trip, or how long can we go without dumping. This post should give you a clear idea of how often and when you will need to dump.

How long will a black water tank last on my RV?

A travel trailer black water tank will will typically last 5+ days if you are a couple camping or alone. If you have kids, expect your black water tank to last less than 5 days. Depending how you use it, you can extend your black water tank to last even longer.

The black water tank on your RV is the last thing you want to have on your mind and deal with. Getting to know the functions of your RV and the in’s and outs, you will have a good idea of the length of time and the maintenance your black tank will need.

RV Black Water Tank Explained

A black water tank will last a long time if you can use the tips below to conserve as much space as you can. For example, if you have two people camping and they fill ½ gallon each into the black tank and your black tank is 25 gallons, expect to get 25 days out of your black tank.

Even if each person used one gallon of space, your black tank would last 12.5 days in your travel trailer. Black tanks typically last much longer than gray tanks. Always make sure to dump at ⅔ full and do not wait until these reach capacity as you would never want an overflow.

Below are 5 sample RV’s with their capacities. These tanks could last a couple of two from 12.5 to 19.5 days using one gallon of waste each per day.

RV Make/ModelBlack Tank Capacity Gallons
Winnebago Micro Minnie25
Keystone Bullet30
Winnebago Minnie25
Dutchmen Aspen Trail28-32
Jayco Jay Flight32.5-39

What is a black water tank?

A black water tank is where any waste water and debris that gets flushed down the toilet goes. Black tank water is hazardous to come in contact with, so always use the proper protections and precautions when dealing with black tank waste water.

Black water tanks are typically mounted under the chassis of the RV adjacent to the gray water tank. When full, black water tanks can add 200-300 pounds of weight to your RV provided they are from 25-39 gallons respectively. Always try to dump your black water before you travel as it sloshes around when you drive and can leave your RV smelling until you air it out.

Do I need Special Toilet Paper for RV?

Yes, you will need special toilet paper for your camper. Typically, if it is sewer and septic safe, it is good to go. It is not necessary to use special super expensive RV toilet paper, but make sure to use septic safe paper. Make sure when you dump your black tank you flush every time to avoid buildup of any paper or debris. We have found this toilet paper to be very nice and have not had any problems with our black tank.

Last update on 2021-06-10 / Affiliate links / Images from Amazon Product Advertising API

Do not allow any other items to go into your black tank besides waste and toilet paper. These can cause damage to your sensors or permanently get stuck inside your black tank.

How to conserve black water tank space in your RV

The easiest way to conserve black water tank space in your RV is to use campground bathrooms as much as possible when you are camping. Also try the tips below to save even more usage.

  • If going number one, try and complete a quick flush with the foot pedal.
  • If going number two, fill the toilet with a little water first, this will help stop any materials from sticking to the bottom of the toilet needing lots of water to bring them down.
  • When going number one, if your water is off, don’t turn it on as you may not need any water to flush.
  • Only use the toilet at night, use campgrounds toilets during the day.

What happens if a black water tank fills up?

You never ever want your black tank to fill up, and you don’t want to know what will happen if it does. This will ruin the thought of your camper if sewage is spilled throughout. Always monitor your black tank usage, and you can always look down the toilet with the valve open. If your tank does back up, it will leak into your RV, simple as that so do not let it happen.

Black water tank sensors are always inaccurate as things may get stuck on the side of the sensors. Always know about how much use you have out of your black water. It is better to be safe and empty it more often than to let it back up on you and give you problems.

If you don’t want to have to hook up your travel trailer or drive your RV off of your campsite, you can always purchase a black or gray water tote. You will dump your tanks into the tote, then wheel them to the campgrounds dump station and be done with it. No messing around with hitching up. We like this one for a smaller tote, and for a larger 4 wheeled one, this is one of our favorites.

Last update on 2021-06-10 / Affiliate links / Images from Amazon Product Advertising API

Last update on 2021-06-10 / Affiliate links / Images from Amazon Product Advertising API

How to empty a black water tank

  1. Put on latex or similar gloves and safety eye wear.
  2. Hook your sewer dump hose to your RV, then to the sewer dump station
  3. Open black tank valve and wait until flow is stopped
  4. Hook up and run black water flush (if equipped)
  5. If you do not have a black water flush, fill toilet with water
  6. Open black tank valve again
  7. Close black tank valve once flow is finished
  8. Empty the gray water tank
  9. Close valves and remove sewer hose from RV
  10. Flush sewer hose with water at dump site.
  11. Install cap on RV dump pipe
  12. Spray bleach mixture on hose, fittings, and anything that came in contact
  13. Put hose and other items away
  14. Throw away gloves

How to keep your black tank from smelling?

To keep your black tank from smelling, use deodorizer tablets after every time you dump. These tablets are relatively inexpensive, and provide the essential enzymes to help break down items in your black tank to flush easier and reduce smell.

Read more about How Long will a Fresh Water Tank Last?

Read more about How Long will a Grey Water Tank Last?

Related Questions

How do I clean my black water tank sensors?

The best way to clean your black water tank sensors is to fill up your tank ½ with water. Add some ice in order to help agitate solids that may have become stuck to the sensors or walls. Drive your RV around taking turns, stops, and accelerations. Dump your tank and your sensors should be cleaned.

Can I dump my black water tank on the ground?

No, you cannot dump your black water tank on the ground. Black water is full of hazardous substances and chemicals and is not safe for the environment or if it is in contact with people. Always wear gloves and eye protection when dealing with your black tank.

Can I leave my black tank valve open?

No, you never want to leave your black tank open as water will flush each time and not bring solids with it. You want a buildup of water and solids to make the flush remove as much as possible. Also, this will leak dangerous sewer gas into your RV which is harmful.

Helpful Items Mentioned in this Article:

RV friendly toilet paper will make your black tank thank you. It will be easier to clean and less smelly. This stuff is still really soft!

A quality sewer hose like our favorite here will not leave you with a mess at the dump station. Do not cheap out on this, nor do you need some expensive $150 hose.

A tote tank such as this 15 gallon or this 42 gallon will keep your trailer at the campground instead of doing dump out runs, saving you time and making life at camp easy.

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Eric

I have been camping most of my adult life and am passionate about having the best camping equipment as well as writing. Combine these two items and you have our site.

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