Composting toilets

[woodscrew]

Airhead

I have lived aboard full time for three years with an Airhead composting head. I love it. No smell-ever. Not when dumping it, not even when using it due to the air being pulled through it. Very simple. No tanks, hoses, seacocks, pumps, deck Pumpout’s etc. No Pumpout charges either. No boat has ever been flooded/sunk from an Airhead. It may not be for everyone but it works for me.

 

[Hippocampus]

Haven’t owned but have spent time on boats with them. Think they’re an excellent choice if coastal. Think traditional maybe a better choice if much time is spent offshore where emptying isn’t an issue. The cur is bulky. Depending on where you are may not be available. When it’s bumpy not pleasant to empty if things go wrong. You need to carry consumables.
On the last boat had one manual head and one elegance. That combo worked great. Actually think good electric heads are less likely to be troublesome in the field if you have a strong macerator and using RO water.
Definitely see a composting and a good quality electric as another excellent option. If commonly in unrestricted areas or nearby access due to need for media don’t think composting would be the best option.

 

[socalrider]

Haven’t owned but have spent time on boats with them. Think they’re an excellent choice if coastal. Think traditional maybe a better choice if much time is spent offshore where emptying isn’t an issue. The cur is bulky. Depending on where you are may not be available. When it’s bumpy not pleasant to empty if things go wrong. You need to carry consumables.
On the last boat had one manual head and one elegance. That combo worked great. Actually think good electric heads are less likely to be troublesome in the field if you have a strong macerator and using RO water.
Definitely see a composting and a good quality electric as another excellent option. If commonly in unrestricted areas or nearby access due to need for media don’t think composting would be the best option.

I've often thought that an ocean crosser might want a composting head plus one that just discharges straight overboard (no holding tank, macerator or Y-valve) for use underway for the reasons you mention above. Seems like the best of both worlds and minimal complexity.

 

[psneeld]

I've often thought that an ocean crosser might want a composting head plus one that just discharges straight overboard (no holding tank, macerator or Y-valve) for use underway for the reasons you mention above. Seems like the best of both worlds and minimal complexity.

Pretty sure if you have a toilet on board a USA vessel, it has to be connected to a type I, II or III MSD (type I and II are treatment devices, type III is a holding tank). The composting or incinerating toilets no, but flushable yes.

 

[socalrider]

Pretty sure if you have a toilet on board a USA vessel, it has to be connected to a type I, II or III MSD (type I and II are treatment devices, type III is a holding tank). The composting or incinerating toilets no, but flushable yes.

I'd thought you could get away with it if there was a shutoff valve on the discharge side that was locked out while in port?

 

[mvweebles]

I've often thought that an ocean crosser might want a composting head plus one that just discharges straight overboard (no holding tank, macerator or Y-valve) for use underway for the reasons you mention above. Seems like the best of both worlds and minimal complexity.

I agree. If the boat has two heads, a traditional head and a compost is an excellent choice. I also agree with you and Hippo about having a direct discharge if primarily paasagemaking. I also agree that newer marine heads are more reliable, but the MSD/holding tank/plumbing/vents are still a weakness. Yes, I've read Peggie's Bible but given the frequency of posts with head issues, reliability remains elusive for many.

Upthread I attached a summary of responses I received to the question "compost head owners - would you do it again?" One of the questions asked was availability of media while cruising, especially the tropics. There were several responses stating no issues, which mildly surprised me. I'd have to reread, but there were several alternative media suggested instead of coco coir including peat moss and hamster bedding from pet stores. I've used coco coir for hydroponic gardens and my sense is carrying enough for a year of cruising would not be difficult.

Peter

 

[psneeld]

I'd thought you could get away with it if there was a shutoff valve on the discharge side that was locked out while in port?

https://www.epa.gov/vessels-marinas-and-ports/marine-sanitation-devices-msds



Who is required to use an MSD?

• Section 312 of the CWA requires the use of operable, U.S. Coast Guard-certified MSDs on board vessels that are 1) equipped with installed toilets, and 2) operating on U.S. navigable waters (which include the three mile territorial seas). 33 U.S.C. 1322(h)(4) (PDF) (10 pp, 170 K).

Not sure if you could get away with not having it plumbed to a holding tank if you also have another operating head that complies.... there aren't many links to that situation. If the toilet was disabled by locking down a "y" valve it may be OK...but I haven't ever seen the written guidance one way or the other. So you may get a mix of enforcement on the water.


Traditionally a bucket is the answer and can be dressed up with a fancy seat mod. But certainly isn't as convenient as an installed overboard toilet.

 

[rsn48]

For the composting toilet, I think some are using cat litter. Upon researching, another method is also becoming popular, pelletized bedding for horses and small animals. The media is suppose to have great absorbency. I think over time, other medias will be found to work quite well, not just coconut coir and sphagnum peat moss.

 

[Moby Nick]

We've been using a Nature's Head for almost 10 years and have always used Peat Moss available at lawn & garden stores.

 

[Art]

Poop/pee... air toilet or flush toilet??? > - > - > You make the call!

Face it... humans excrete a lot of dirty/filthy digested wastes. #1 and #2 excrements need to be dealt with in one or another form of correct sanitary manner.

Imagine if each house, motel/hotel room, boat, RV... etc, etc... used air/compost toilets. Then comes the need to very often drop off "actually non composted" bags of [possibly disease carrying] solid to semi solid human digestive tract waste into dumpsters, garbage cans or even compost piles - compost piles that are - specifically designed for "clean" food waste that is meant to becomes fertilizer before it is humanly eaten/digested/execrated. Imagine the "customer" crunch when many have air toilets and many need to gang into public rest rooms to empty their "air toilet's" jug of urine. Then imagine how many will say "F-It" and dump the liquid in that jug into "some-other" location. And then, the urine jug needs to be cleanly flushed out too!

One item regarding unfettered human population explosion is an enormous problem for correctly dealing with human waste.

Well - you get the picture!

Let me say: I've been closely following this need for better human waste management ever since early 1970's when the Rockefellers introduced "Clivus Multrum" compost toilets. In early 2000's I tried to start a Nor Cal distribution/installation business for compost toilets. Code restrictions, flat out "against the law" statutes, insurance restrictions, permit restrictions, planning comity by-laws, HOA mandates... and by far the most disturbing... recorded infectious disease transmission health problems. Suffice it to say; I did not pursue the opening of a compost toilet installation business.

Don't get me wrong. I'm not against compost toilets. Neither am I against sewage sanitation plants. What I do desire is that we humans would appropriate more funds and expend more inventive-intelligence toward the collection of, cleansing of and healthful disbursement for human waste products.

Here's a video I feel is on-point regarding an RV couple's compost toilet.

 

[mvweebles]

As mentioned by a previous post, a more correct term for "compost toilets" such as Nature's Head, Air Head, etc is "dessicating toilet.' Separating the fluids from the solids makes a huge difference.

Art, I'm surprised it took this thread so long before the infectious disease card was played. Likelihood is probably on par with getting carbon monoxide poisoning from sitting in traffic.

Peter

 

[MurrayM]

I was motivated in a previous thread to dig up California laws about putting desiccated turd bits into municipal landfills via dumpsters in marina parking lots. I'll let someone else wallow around the Internet to find it this time.

There was no problem in doing this, as landfills are designed to accommodate backyard dog crap, baby diapers, old codger diapers/Depend underwear, etc.

 

[Art]

As mentioned by a previous post, a more correct term for "compost toilets" such as Nature's Head, Air Head, etc is "dessicating toilet.' Separating the fluids from the solids makes a huge difference.

Art, I'm surprised it took this thread so long before the infectious disease card was played. Likelihood is probably on par with getting carbon monoxide poisoning from sitting in traffic.

Peter

Peter - You call it a "card"... it's not my card!

I was simply including reference to the medical report provided me when I was researching going into compost toilet sales and installation biz some 20 years ago. The report did disturb me; and, it was a primary reason why the county refused my ability to operate a biz such as that.

I don't doubt that the threat of infectious disease transmission is probably quite limited. However, that the county within, that I was researching for a business license denied me the license using that disease factor outstanding... did open my eyes.

 

[mvweebles]

Peter - You call it a "card"... it's not my card!

I was simply including reference to the medical report provided me when I was researching going into compost toilet sales and installation biz some 20 years ago. The report did disturb me; and, it was a primary reason why the county refused my ability to operate a biz such as that.

I don't doubt that the threat of infectious disease transmission is probably quite limited. However, that the county within, that I was researching for a business license denied me the license using that disease factor outstanding... did open my eyes.

Fair enough Art. But there is a significant difference in how the modern crop of desiccating heads work. It would take months and months to truly compost mixed liquid/solid human waste. The amount of energy and work required to process the mixture is significant, but that is how municipal systems are setup. Urine, while high in acid and salts, is relatively inert and requires minimal processing, especially compared to solid animal waste.

I can't make heads nor tails out of many health and building codes. Sometimes, common sense prevails. The conventional wisdom for municipal sewage systems (including the pump out station used by boats) is to mix the solid/liquid waste together, add a LOT of water, transport it many miles to a treatment plant on the outskirts of town, then use a LOT more water and a bunch of energy along with some chemicals to produce non-potable water. On the other hand, you have a compost/desiccating toilet that isolates the solids, dries them out, then the waste gets returned to the earth either directly or via landfill that is designed for long term composting of organic matter. Yet somehow this is "gross." I just don't get it. Sounds responsible to me, especially compared to the sewage processing equation. We live in a curated society where the objectionable parts of life are behind-the-curtain.

Peter

 

[jsplichal2]

Wife and I bought the boat five years or so ago. PO installed a CHead aft and Nature’s Head fore. We have been bemoaning this decision for about 4.75 years. Finally just purchased a marine elegance bowl and will replace the CHead. Will keep the Natures Head but will only use it for urine. I do not recommend the change but if anyone decides to give it a go - why not just change one head out and give it a go before committing both heads? Or just go with one of each like we will? Best of both worlds. And have someplace for guests to use the lav. Additionally plan on getting one of the purasan type systems and would pose the question to anyone thinking about spending the money on composting toilets, why not keep current heads in place and spend a little more on one of these type of systems?
Before any of the pro composting group answers with the cost savings/low mx answers - I was just posing the question to think about. Not start a long back and forth about which system is better.
On a separate note - if anyone is in the market for a used CHead PM me.

 

[Adopo]

I cannot count the number of boats I have been on that smell like sewage below, or that at least give you that occasional wisp. Often the broker will say it is the hoses need replacing, but either way it is just awful. I have a friend who swears by the composting, and he says it has NO odor. To me it would be like a big cat box, with you being the cat. For the life of me I don’t know how the poop doesn’t stink.

 

[MurrayM]

...For the life of me I don’t know how the poop doesn’t stink.

It's covered by the coconut coir, then dries out.

No molecules being caressed off the poops surface by gentle breezes in your boat, so no molecules to snuggle into your olfactory system

Airheads have a tiny permanent fan going all the time anyways.

 

[jgwinks]

Why is he nudging you towards composting head?

Personally, I think the ultimate setup would be a 2 head boat - one conventional, one composting. As mentioned, composting doesn't work well for a crowd, and there are people like Mako who find the idea repulsive. Having a split head setup would be best of both worlds.

Peter

That's our plan, 2 heads on the boat and planning to put in a C-Head in the aft one. That toilet leaks and the PO didn't have it hooked up to the new holding tank anyway. Forward toilet is hooked up and we'll have that available for guests. We have some friends that I'm sure would be grossed out by the composter so they can use the conventional one. In our home port getting pumped out is a real problem so we think the composter will be a great improvement.
As for dumping the liquid OB, I'm sure a lot of folks using them do that, I've even seen accounts of off-grid cabins just running it down a hose a ways away from the cabin and the well. Doesn't cause any problems apparently.

 

[Frosty]

I For the life of me I don’t know how the poop [in a dessicating toilet] doesn’t stink.

A big part of it is not combining the liquids and solids. That's one reason chicken poo is so awful (they do both together as I understand it).

Not saying the separation is all of it, but it's a huge contributor to "not stink." Mixed pee/poo is much worse.

 

[Art]

It's covered by the coconut coir, then dries out.

No molecules being caressed off the poops surface by gentle breezes in your boat, so no molecules to snuggle into your olfactory system

Airheads have a tiny permanent fan going all the time anyways.

Murray

I've been wondering about that little evacuation fan on compost toilet when its inside closed up boats/RVs for periods of time. Sooo... figured I'd ask you.

What if... For whatever reason: With C-Toilet not properly emptied/cleaned.
When boat or RV is left unattended for months at time and that fan stops working [batt goes dead, or fan seizes up, or electric connection gets too corroded] - Does the closed vehicle become enmeshed-in/permeated-with decaying/compost fecal matter stench??

 

[MurrayM]

Murray

I've been wondering about that little evacuation fan on compost toilet when its inside closed up boats/RVs for periods of time. Sooo... figured I'd ask you.

What if... For whatever reason: With C-Toilet not properly emptied/cleaned.
When boat or RV is left unattended for months at time and that fan stops working [batt goes dead, or fan seizes up, or electric connection gets too corroded] - Does the closed vehicle become enmeshed-in/permeated-with decaying/compost fecal matter stench??

Well, first off, it can't rot/stink because the poop is dry.

You have to add water and break up the coir bricks before it goes into the head, and it's pretty obvious when it's too wet.

It's been awhile since I've thought about the way it works or read anything about it, but this should be close...

There are 'airtight' seals between the lower holding unit and the seat you sit on, so no stink gets out that way. The incoming air port (with a bug screen) is lower down on one side than the outgoing air port (also with a screen) higher up on the other side.

During winter when we hardly use our boat I occasionally have to add a bit of water to the coir so it doesn't dry out too much, so pretty sure if the fan stopped it would naturally dry very slowly and not be a problem.

 

[mvweebles]

Murray

I've been wondering about that little evacuation fan on compost toilet when its inside closed up boats/RVs for periods of time. Sooo... figured I'd ask you.

What if... For whatever reason: With C-Toilet not properly emptied/cleaned.
When boat or RV is left unattended for months at time and that fan stops working [batt goes dead, or fan seizes up, or electric connection gets too corroded] - Does the closed vehicle become enmeshed-in/permeated-with decaying/compost fecal matter stench??

Art - I do not have extensive experience with these heads, but many owners state they installed the head with intention of installing the fan later, and never did as they didn't feel the need. I find that a bit hard to believe but the sentiment is fairly universal.

As mentioned before, urine causes more issues than excrement. It really starts to stink after a relatively short period (days). So while poop has the ick-factor, the real issue is urine, which makes sense - it's urine that causes the crystalline build-up on hoses.

Odor in the solids' side of the system is always related to too much moisture. This is either improper use; or a bout of diarrhea. Some users have reported problems with gnats/fruit-flies. Both of these issues can be a non-trivial annoyance and should not be entirely minimized.

There is no free lunch - there are issues with either a traditional marine head system or a compost head. My decision for my 1-head W36 really came down to it's just the two of us and compost head works fine. I'm not crazy about peeing while sitting, but I got used to it. If I had a larger boat and planned on guests, I would need to return to a traditional system.

Bottom line - the Compost Head is a viable system. It requires some compromises and you have to decide whether those compromises offset the benefits of simplicity and reliability.

Good luck

Peter

 

[Art]

Bottom line - the Compost Head is a viable system. It requires some compromises and you have to decide whether those compromises offset the benefits of simplicity and reliability.

Good luck

Peter

I agree with you... C-Head is a viable system. In some placement positions [i.e. needs to be fulfilled] it is the appropriate system. For other placement positions it is not.

That said: Please read my post # 40 - and watch the full video on it. You will realize that I have considerable background research regarding compost toilets. RV couple in the video - tell it like it is! Each to their own...

Different strokes... for... different folks!

Cheers!!

 

[socalrider]

What if... For whatever reason: With C-Toilet not properly emptied/cleaned.

When boat or RV is left unattended for months at time and that fan stops working [batt goes dead, or fan seizes up, or electric connection gets too corroded] - Does the closed vehicle become enmeshed-in/permeated-with decaying/compost fecal matter stench??

I had a C-head on our sailboat before our current twin airheads (which I prefer for a few reasons). The C-head is a simpler and less expensive system, and it's not sealed like the air head. I never installed a vent fan. Even so, I never had odor issues. The mfg recommended installing one in humid areas.

It sounds counter-intuitive, but as stated above, separating the solids and liquids really does mitigate the odor so long as you deal with the liquids on a regular basis. I found a squirt or two of diluted Campa-chem also helps prevent pee odors should they arise - but really not necessary if you keep it emptied.

 

[jsplichal2]

I read somewhere and have been using vinegar to stop the pee smell. And it works well. Poor some undiluted vinegar in the pee area before use and also have a spray bottle filled with a water vinegar mix that we use to spray/flush after use.

 

[socalrider]

I read somewhere and have been using vinegar to stop the pee smell. And it works well. Poor some undiluted vinegar in the pee area before use and also have a spray bottle filled with a water vinegar mix that we use to spray/flush after use.

Yes that works too - it's been what we're using since I left my campa-chem on our last boat. I might go back to camp-chem because the vinegar smells like... vinegar, but I've been too lazy to hunt it down.

 

[Hippocampus]

On the traditional side find one thing as made the biggest difference for smell.

Use nothing but RO water in the heads.

RO water has such low mineral content crystals don’t form in hoses. Unless you’re in a marina or for another reason can’t make water don’t use the pee button. Just the higher volume flush. Don’t follow the yellow mellow mantra. Stagnant super concentrated solution = crystals. Flush until there’s no contaminated effluent in your hoses for 1 and 2.

People undersize vents. If you have adequate vents and keep them open you should have a predominance of aerobic bacteria in your heads. It’s the anaerobes that I think produce the majority of the smell. Do this and I think there’s no reason to put any additives in your heads beyond olive oil rarely for the valves if required.

I won’t tolerate either bilge smell nor head smell in a space where I live. A totally clean, dry bilge and a wee bit of attention to the heads prevents that situation and makes for a more pleasant environment . We also wipe down all interior surfaces with a weak vinegar solution and a drop of Dawn. In humid conditions mold is a major issue and also can be prevented with just a little bit of work. Boats shouldn’t have any boat smell at all.

 

[Art]

On the traditional side find one thing as made the biggest difference for smell.

Use nothing but RO water in the heads.

RO water has such low mineral content crystals don’t form in hoses. Unless you’re in a marina or for another reason can’t make water don’t use the pee button. Just the higher volume flush. Don’t follow the yellow mellow mantra. Stagnant super concentrated solution = crystals. Flush until there’s no contaminated effluent in your hoses for 1 and 2.

People undersize vents. If you have adequate vents and keep them open you should have a predominance of aerobic bacteria in your heads. It’s the anaerobes that I think produce the majority of the smell. Do this and I think there’s no reason to put any additives in your heads beyond olive oil rarely for the valves if required.

I won’t tolerate either bilge smell nor head smell in a space where I live. A totally clean, dry bilge and a wee bit of attention to the heads prevents that situation and makes for a more pleasant environment . We also wipe down all interior surfaces with a weak vinegar solution and a drop of Dawn. In humid conditions mold is a major issue and also can be prevented with just a little bit of work. Boats shouldn’t have any boat smell at all.

I agree: "Boats shouldn’t have any boat smell at all." i.e. Bad Boat Smells, that is!

IMO, definition of the top 4 bad boat smells: Sewage / Motor and/or Fuel / Mildew / Dead Sea Life [specifically - rotten fish]

However, there are aboard boat marine smells that are enjoyable... there are also in house forest smells and wide open beach smells that are inviting. In other words... There are BIG differences between good and bad smells.

Regarding boat smells: First of all, and in general, there is a bit of a difference between wood, fiberglass and metal boat smells. Each when kept clean enable the enjoyment of pleasing marine smells.

In regard to [mentioned 3 paragraphs above]:
"Sewage / Motor and/or Fuel / Mildew / Dead Sea Life [specifically - rotten fish]" Each is self explanatory. Each can be well controlled by properly handled and maintained condition-needs.

For used boat buyers... Each boat smell condition-need should be well looked into before a purchase $$$ offer is made. Unpleasant boat smell circumstances located may present a simple fix - or - things may present considerable investment to overcome the undesirable smell. So... chose the used boat you buy wisely. Don't be afraid to adjust [lower] your $$$ offer in accordance with repair costs required. And... Don't be afraid to walk away from any deal if necessary - there are thousands of other boats for sale that may please you much better!

 

[FF]

"I agree: "Boats shouldn’t have any boat smell at all." i.e. Bad Boat Smells, that is!"

This is very difficult as most boats will have hidden wood (backing plate) some where that with a tiny leak will dry rot and hive that Old Boat Aroma.

"When boat or RV is left unattended for months at time and that fan stops working [batt goes dead, or fan seizes up, or electric connection gets too corroded. -

Does the closed vehicle become enmeshed-in/permeated-with decaying/compost fecal matter stench??""

Not at all as only fresh damp #2 waste stinks and an hour after the waste is tumbled into the tank it is quite dry

We used a unit for years in a cottage , so have experience with emptying the collection chamber.

 

[catalinajack]

Vinegar is an acid. Acid kills aerobic bacteria leaving anaerobic bacteria to produce its nasty odors. No acids in holding tanks. Not good.

I read somewhere and have been using vinegar to stop the pee smell. And it works well. Poor some undiluted vinegar in the pee area before use and also have a spray bottle filled with a water vinegar mix that we use to spray/flush after use.