Twin Bucket Toilet FAQs

Frequently Asked Questions about the Emergency Twin Bucket Toilet

Why do we need a toilet in our emergency supplies? Quakes and shakes mean pipe-breaks. You shouldn’t flush your toilet after an earthquake. All the pipes in your septic system or your municipal sewers need to be checked out first.

What’s wrong with porta potties? Community porta potties may work in minor emergencies where transport and treatment infrastructure remain intact. The same is true for household chemical toilets. But in a severe seismic event, disposal and treatment options disappear. In Christchurch NZ the use of chemical toilets made the situation worse.

What kind of bags do you recommend? Ideally, use trash compactor bags (they are extra thick plastic) or double bag regular trash bags. An emergency is not the time to save plastic. You don't want to risk your health by using thin plastic bags that could break!

Can’t we just put a plastic garbage bag in our home toilets but not add water? Think about it. How would you store bags full of excreta until you could dispose of them? And they could break when you are transferring or storing them—ick! And where would you send the bags and how? On trucks with no fuel on broken roads?

Why two buckets? Imagine you have a single bucket toilet. How fast will it fill up? Pretty fast right? If you have one for pee and one for poo which will fill up faster? The pee bucket, right? As for the poo bucket it won’t fill so fast. Keep the poo in a container to avoid spreading germs.

What do you mean “contain the pathogens”? Keep the poo in a container. Cover poo lightly with carbon material to dry it out. Don’t put on a tight lid because it needs air. You can cover the bucket with a screen or piece of cloth to keep flies out.

Doesn’t the poo bucket smell? Very little. The bad odors result from mixing poo with pee.

What about the pee bucket? Pee doesn’t usually contain pathogens, unless someone in your family is sick. For the pee bucket you need a lid that fits well. When the bucket gets full, cover it and set aside. Or you can dump it in any other container with a lid. Pee is simply stored and its pH rises naturally to destroy any remaining bugs.

How much does a person pee everyday anyway? Between one and two quarts. That’s about 6 cubic feet a year. The amount of urine depends on mostly on body weight and intake of food and drink.

What about poo? An adult produces less than two pounds a week. As poo dehydrates volume decreases. A year’s work is about one and a half cubic feet, an amount you could carry in a backpack.

Where did the idea for the twin buckets come from? From New Zealand after the 2011 quake, but only when people learned that chemical porta potties and pit latrines spoiled the environment. Not mixing urine and feces, however, is a proven principle of ecological sanitation. UDDTs, or urine-diverting dry toilets are increasingly used throughout the world. You can find them in green buildings such as headquarters of the Bullitt Foundation in Seattle.

Are the twin buckets a humanure system? No. Humanure usually uses single bucket to collect a pee+poo mix and requires fairly labor intensive thermophilic composting treatment.

Can you say more about carbon material? Keep the carbon covering material near the poo bucket in a separate container with a scoop. Cover each deposit lightly to deter flies and help feces dry out. You can use sawdust or shavings, finely shredded papers, coffee husks, or the coir fiber from the convenient bricks that are sold as gardening supplies. But remember, if you intend to empty buckets into your septic tank, just let the poo dry out WITHOUT adding carbon material.

Where’s the best place to get buckets with lids? Rather than buy new ones, first try to find used buckets. The FDA prohibits bakeries and restaurants from reusing buckets commercially for food. The Safeway gives away 3.5 gallon buckets with tight fitting lids. Hardware stores have new buckets with lids. An excellent online source is US Plastics, where buckets and lids come in a variety of colors. How about a red and green Twin Bucket Hygiene Kit for under the Christmas tree?

I can’t find a plastic snap-on toilet seat. What do I do? Snap on lids are usually available online for about $10. Consider buying a single bucket camping toilet (and adding a bucket) or adapting a regular toilet seat to fit buckets. Comfortable alternative seats can be made using inexpensive pipe insulation or a pool noodle.
What about the long-term disposal plan? We can't emphasize enough how important it is to get your neighbors involved in planning for a long-term disaster scenario. Work together to ensure everyone has adequate emergency response supplies, including a Twin Bucket system. Discuss what you would do in a scenario where long-term storage is needed (i.e. emergency responders and garbage trucks can't access your road). Bear in mind that human waste produces gases that can lead to bag breakage, so bags need to be monitored for gas buildup and off-gassed occasionally! Does anyone have a 55-gallon drum for waste bag storage? Does anyone have a pit where waste can be buried (removed from the plastic - be sure to have nitrile gloves in your kit!) so it can decompose naturally? In the latter scenario, be sure the pit is far above the water table to avoid contaminating groundwater.

Can you explain more about the gas buildup in sealed bags? Methane-producing microorganisms (methanogens) have a heyday in anaerobic (without oxygen) environments. The production of methane (and other) gases can lead to build-up in sealed bags, so it is important to monitor bags during long-term storage for gases and open them to release gas before the bag breaks. Please do so in an open-air environment!

Margot Kleinman

September 6, 2024

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