Written by:

David Hosea

Last updated: November 1, 2023

Composting toilets are a great alternative to traditional flush toilets, especially for RVers because they do not require water for flushing, which is a significant advantage for RVers who often boondock or camp in locations with limited water availability.

Composting toilets turn human waste into trash or a valuable soil amendment, which can be used as fertilizer for gardening or ornamental activities. However, there are some legal considerations and precautions to consider when emptying a composting toilet.

In this article, we will discuss the legal considerations first, then we will discuss how to empty a composting toilet.  We will also discuss where to dump urine, and how often to dump a composting toilet.

Legal considerations

Dumping solid waste from a composting toilet onto public land is illegal because it is a hazard to public health.

The term, “composting toilet” is misleading because it does not actually compost waste.  Composting requires time and temperature to kill bacteria.  Most RVers need to empty their solid waste bins well before composting occurs and composting toilets will not reach the temperature required to kill the bacteria.

Public land agencies such as the National Park Service and Bureau of Land Management require waste be disposed of in receptacles made for that purpose.  For composting toilet waste, that means vault toilets, flush toilets, or trash bins.

States and counties have their own rules as well, but placing solid waste mixed with an absorbent material like coco coir into a trash bag and sealing it, then tossing into the trash is legal.  It is like throwing diapers or bagged dog poop away, so it isn’t an issue.

“No discharge zones” are found near or in sensitive marine environments, especially in coastal and inland waterway areas.  They protect water quality and sensitive aquatic ecosystems from pollution caused by discharged wase, including sewage, from boats and RVs. 

Check with state environmental agencies or the Environmental Protection Agency for locations and regulations related to non-discharge zones in areas you plan to visit.

How to Empty a Composting Toilet

Composting toilets divert liquid and solid waste into separate tanks, and each must be emptied independently.  Liquid waste is dumped into dump stations, vault toilets, or flush toilets.  Solid waste is mixed with an inert medium such as coco coir, then dumped into a vault toilet or trash bag and thrown away. 

The specific process for emptying a composting toilet will vary depending on the model, but these general steps can be followed:

1. Protect yourself by wearing gloves and a dust mask.
2. Remove the solid waste container from the toilet.
3. Dump the compost into a vault toilet or trash bag.
4. Use a scraper, if needed, to remove waste that may be sticking to the side of the container. then toss the bag into an appropriate trash bin or container. 
5. Remove the liquid waste container from the toilet.
6. Dump the liquid waste into a larger container for disposal later, or dump into a vault toilet, flush toilet, or dump station.
7. Replace the solid and liquid waste containers.
8. Wash your hands and clothes thoroughly.

Where to Dump Urine from a Composting Toilet

Urine from a composting toilet can be dumped in campground dump stations, vault toilets, public bathrooms, or any flush toilet. 

Local jurisdictions address dumping urine, or gray water on the ground.  RVers should research local regulations to ensure compliance.

Even if legal, RVers should consider the environmental impact of urine disposal. If allowed, it’s a good practice to dilute urine with water before pouring it out to minimize its impact. 

How Often to Dump a Composting Toilet

The frequency of emptying a composting toilet depends on the size of the toilet and the number of people using it.

A couple living full time in an RV could go 2-3 weeks before emptying the solid side of the composting toilet.  The liquid side will need emptying every few days. A larger family using one toilet will need to empty it more often.  A family of four RVing on the weekends may only need to empty it every two to three months.  But if using it on the weekends only, why wait that long?

Conclusion

Emptying a composting toilet may seem a little difficult at first because you must get comfortable with working up close and personal with human waste.  But just like emptying an RV’s black tank, it will become a non-event over time. 

It is important to follow the legal considerations and guidelines for disposing of composting toilet waste, as well as to know how to properly empty the toilet, where to dump the urine, and how often to dump the toilet.

I hope that this article answered those questions.

Also, you might be interested in our article on how to empty black tanks. Read here.

Let us know if this article was helpful and we’ll see you down the road!

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