Overboard discharge of holding tank.

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I can't believe all this talk of flush counters. What a complicated / over the top way of working! It's equivalent to not being prepared to drive a car unless it has a range estimator on it so you know how many miles you have left. That's a relatively new feature on cars, but it's by no means a must-have, essential, can't-do-without function!
Cars have had fuel tank gauges on since the early 1900's, and that's been perfectly adequate for around 100 years without people running out of petrol all over the place.

In the same way, it's perfectly workable to fit a tank gauge on your waste tank, and be able to manage it very successfully. When the gauge gets up to around 3/4, start making arrangements to get it emptied before it gets completely full.
Is it that hard to do? Do you really need to know down to the very last flush?

There are plenty of gauges around now that don't use moving parts which could get gunged up and require cleaning. Mine is effectively a pressure gauge which measures the head of liquid above it. But there are others that bubble air through a tube, and measure the air pressure required to push the air through the tube.

KISS. Keep it Simple, Stupid.
 
And actually, USCG regs require that you have the ability to know when the tank is at least 3/4 full. If the tank is made of a material and is in a readily accessible location that allows visual inspection, no mechanical monitor is needed...but if it's not, you're required to have one.

I never heard of that regulation about requiring to know when 3/4 full.
Never heard of anyone being asked during an inspection or boarding.

I have the old "snake river" system that uses "tape" on the outside of the (fiberglass) tank. Seems to work fine and is dead simple.
 
Pomp it before you go and then anytime you dock overnight,or fuel. At the dock we pump out each week weather it is needed or not. Make it easy and you won't have to make it into a science project.
 
Peggy, do you know of any type of flush counter for a marine head?

You're kidding, right? If you pump a manual toilet 6x to move bowl contents to the tank, is that 6 flushes or one? What if more pumps are needed? How many seconds on an electric flush button is a flush? Some electric toilets use more flush water than others...so what possible value could a flush counter have???

I never heard of that regulation about requiring to know when 3/4 full.


33 CFR 159.83
Each sewage retention device must have a means of indicating when the device is more than 3/4 full by volume.

It's the reason for the SeaLand TankWatch I.
 
I can't believe all this talk of flush counters. What a complicated / over the top way of working! It's equivalent to not being prepared to drive a car unless it has a range estimator on it so you know how many miles you have left. That's a relatively new feature on cars, but it's by no means a must-have, essential, can't-do-without function!
Cars have had fuel tank gauges on since the early 1900's, and that's been perfectly adequate for around 100 years without people running out of petrol all over the place.

In the same way, it's perfectly workable to fit a tank gauge on your waste tank, and be able to manage it very successfully. When the gauge gets up to around 3/4, start making arrangements to get it emptied before it gets completely full.
Is it that hard to do? Do you really need to know down to the very last flush?

There are plenty of gauges around now that don't use moving parts which could get gunged up and require cleaning. Mine is effectively a pressure gauge which measures the head of liquid above it. But there are others that bubble air through a tube, and measure the air pressure required to push the air through the tube.

KISS. Keep it Simple, Stupid.


I understand your point. OTOH, I have tank level monitors that don't work well. It shows me the tank is either "not empty" or "full". Yes, I will see if I can pull it out and see what I can do to improve it. My tank construction will not allow an exterior sensor.

As for simple, if I knew that the holding tank would handle about 50 flushes and that so far we have flushed the head 37 times, that is very simple and much more accurate than a gauge that simply tells me the tank is not yet full. So, I may be stupid, but that seems simple to me.
 
If you have a toilet that "flushes", you could count each time you flush. If you have a manual toilet (as I do), a "flush" varies depending on the number of times the user pumps the handle (and of course, the volume of sewage introduced into the toilet). I can't imagine having a piece of paper in the head where every user must account for his or her toilet use.


I couldn't get anywhere with the link Peggy posted but I do have a level sensing device. It just doesn't work and unless I can find a way to keep poop from sticking to the inside of the tank, it never will.
 
I couldn't get anywhere with the link Peggy posted

I didn't post a link...the forum software highlighted the word sewage as a search term. What I quoted is the law as stated in Title 33 of the Code of Federal Regulations part 159.83 If you need proof, here's the link to it:

33 CFR 159.83 - Tanks Level indicator.


I do have a level sensing device. It just doesn't work and unless I can find a way to keep poop from sticking to the inside of the tank, it never will.

You can't keep it from sticking to the walls, but there are products that will remove it...I'm told that NoFlex is one, and that regular applications will prevent it. You have nothing to lose by trying it.

Peggie
http://www.amazon.com/New-Get-Rid-Boat-Odors/dp/1892399784/
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein
 
I have tank level monitors that don't work well. It shows me the tank is either "not empty" or "full". Yes, I will see if I can pull it out and see what I can do to improve it. My tank construction will not allow an exterior sensor.

If you can pull out the senders, you can replace 'em. The SCAD system has an internal sender...it's sealed in a PVC tube, so it never comes in contact with the tank contents, therefore can never become clogged.
SCAD Internal Sender Instructions

It'll cost you a little less if you buy it directly from the mfr Profile Tank Monitors

Peggie
http://www.amazon.com/New-Get-Rid-Boat-Odors/dp/1892399784/
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein
 
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I do have a level sensing device. It just doesn't work and unless I can find a way to keep poop from sticking to the inside of the tank, it never will.

You can't keep it from sticking to the walls, but there are products that will remove it...I'm told that NoFlex is one, and that regular applications will prevent it. You have nothing to lose by trying it.

Peggie
http://www.amazon.com/New-Get-Rid-Boat-Odors/dp/1892399784/


Yep, there are other tank level monitoring systems, too.

We've been experimenting with Noflex for the last couple years. The verdict is still out... but then part of that is because I don't have easy sight-lines to the tank itself... so don't check it directly very often...

I'd say it'd be worth a shot, though. If it works for a given situation, it's a relatively easy solution.

-Chris
 
Peggy, do you know of any type of flush counter for a marine head?

Dave
How about a bilge pump counter? ?

I'm with Peggy here...level sensor makes alot more sense. Get it working or replace it would be my approach
 
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Dave
How about a bilge pump counter? ?

I'm with Peggy here...level sensor makes alot more sense. Get it working or replace it would be my approach


Yeah, the holding tank sensor is one of the many winter projects that I planned. Peggy, thank you for the links. Bachus, a bludgeon pump counter is a great idea. I will check it out.
 
consider using what the rv'rs use, well some of us at least.

capacitive tank level monitors. "Non contact".

just an example.. (no affiliation)

LED lighting, soundproof, Sailor's Solutions Inc.

TM01_2.jpg
 
Capacitive tank level indicators have widely used the marine industry for more than 20 years. The Snake River systems were the first. The original SR company folded when they couldn't compete with the much higher quality Profile tank monitors Profile Tank Monitors (the Snake River brand name has had several owners since, but none who've ever gotten it off the ground again.) The SCAD systems are a private label version of the Profile systems.
 
Interesting thread. Our boat includes a Raritan treatment system. It was designed to run blackwater through the ElectraScan and then overboard as a primary mode, with the ElectraScan and holding tank as a secondary. This design philosophy has left us with a holding tank that is obnoxiously small. Installing a tank monitor hasn't risen to the top of my maintenance list yet, but I'm finding good information about available systems here.
 
Those waters NOT designated "no discharge" are getting harder and harder to find in the Northeast. I'd hesitate to recommend an expensive install which can be made illegal to use with the stroke of a pen.



Peggy nailed it. One more thing though; rumor has it you need to disconnect BOTH ends of a hose. According to this story, disconnecting one end will still get you that supposed citation we've all heard about but never actually known anyone who's seen.

There are solutions for both of those questions. It would be nice though to have an electronic counter on an electric flush toilet that would tell you the number of cycles. That would seem to be the most accurate and foolproof method to know how much has gone into the holding tank.

It wouldn't tell you how much fluid went into the tank.

It's great that you monitor you poop tank like a hawk. But it's unrealistic to think others are bad captains if they get caught short once in a while.

All it takes is say a Vac U Flush with a stuck bowl valve to fill you holding tank without your knowledge.

Many boats have holding tanks that are way to small for the number of heads feeding them. Or to be really useful for anything but a couple of days away from a pumpout.
 
I did a little research into the issue of holding tank monitors and got hung up in the CFR language. A marine engineer in the yacht business passed this along to me. So if you are worried about compliance because you don't have a holding tank monitor....you may want to reat the CFRs or check further.

He wrote pretty much this .....

Yep, tank monitor .... the tank does not have to be labled, it does not have to have a level indicator. It does not have to be built by any specific manufacture or labled as a certified tank.

Where do most holding tanks in the world come from? They are sold by the plastic tank folks who put a fitting where you want and ship them to you.

The operative CFR paragraph for the monitoring that works for recreational boats is:

(c) Any device certified under this section need not comply with the other regulations in this part except as required in paragraphs (b)(2) and (d) of this section and may not be labeled under § 159.16.

Certified means (b) Any Type III device is considered certified under this section if:

(1) It is used solely for the storage of sewage and flushwater at ambient air pressure and temperature;

With regard to 159.53(c) :

(c) Be designed to prevent the overboard discharge of treated or untreated sewage or any waste derived from sewage (Type III).

Which means the tank has to hold the sewage, not just be a pass through or a wide spot in the toilet discharge piping.
 
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I'm thinking about Incinolets. Pros - no plumbing, no holding tank, no overboard discharge, no plugs to clear, no thru-hulls. Cons - initial expense ($2k), hefty vent line, major power requirement (1.5kwh/use!), some owners have complained of noisy exhaust fan and odors.
 
It wouldn't tell you how much fluid went into the tank.



It's great that you monitor you poop tank like a hawk. But it's unrealistic to think others are bad captains if they get caught short once in a while.



All it takes is say a Vac U Flush with a stuck bowl valve to fill you holding tank without your knowledge.



Many boats have holding tanks that are way to small for the number of heads feeding them. Or to be really useful for anything but a couple of days away from a pumpout.


Many boats have a smaller fuel tank than they would like, less water tankage than they would like, and hardly anyone has a battery bank that is as large as they may want. Even so, not that many run out of fuel, run out of water, or run their batteries down with no genset to save them. If captains can manage those, they can manage a holding tank. In my opinion the difference is that many captains feel that the consequences of mismanaging fuel, water or power are more serious than mismanaging a holding tank. The reason for that is that in the back of their mind is always the option of surreptitiously discharging their holding tank.

I have gotten caught short with a full holding tank a few times. In other words, I have failed at managing my vessel. A couple decades ago I discharged illegally as the only pump outs that could be found were inoperable and it was a three day trip to get to legal discharge waters in the Canadian waters of the Strait of Juan de Fuca. have since been surprised by a full holding tank a couple times. Now It means that I interrupt my plans to make an unplanned trip to a pump out. Now days, that usually means I may have to go 5-6 nm to reach one. It just makes me more diligent to avoid this situation.
 
Which means the tank has to hold the sewage, not just be a pass through or a wide spot in the toilet discharge piping.

You've done an excellent job of ferreting out the legal definition of a Type III MSD (holding tank) without wandering off into the weeds that only apply to Type I and II MSD mfrs. But 33 CFR 159.53(c) only defines a Type III...not a word about devices that monitor the amount IN the Type III or the legal requirement for a means--which, btw, can include visual inspection--of knowing when the tank is at least 3/4 full. You'll find that in 33 CFR 159.83 - Tank level indicator.

Y'all might find this list of definitions pertaining to vessels that include, but aren't limited to sanitation informative kinda fun...they don't include any mention of tank level monitors either, but useful anyway 33 CFR 159.3 - Definitions.
 
That's they type, but not the brand of the system I installed that doesn't work if sewage sticks to the inside of the tank wall.

In marine tanks, it's the animal fats in waste that build up on the wall of the tank. As I posted earlier, NoFlex should take care of that. But because RV toilets use so little flush water, they have a buildup in their tanks that most marine tanks don't: urine crystals (struvites). At a boat show in California this spring, I ran into a company who makes a product specifically formulated to remove and prevent struvites. He claimed to have pretty good distribution in the RV market, was at the boat show to explore marine market potential. The company is called Tech Tanks...phone is 800-625-7945. You might want to give 'em a call.
 
Interesting thread. Our boat includes a Raritan treatment system. It was designed to run blackwater through the ElectraScan and then overboard as a primary mode, with the ElectraScan and holding tank as a secondary. This design philosophy has left us with a holding tank that is obnoxiously small. Installing a tank monitor hasn't risen to the top of my maintenance list yet, but I'm finding good information about available systems here.

The discharge of treated waste from your ElectroScan is legal everywhere in your waters--actually everywhere on the whole west coast north of Santa Barbara except for one small harbor off SF Bay (Richardson Bay) and a few misguided marinas in WA and several provincial park anchorages in BC...so you should only have to use your tank so rarely that even 10-15 gallons should be more than adequate.
 
Unfortunately, there have been repeated movements to have all of Puget Sound declared a ND area. They have not yet been successful, but I am afraid that they will be soon. If it weren't for that concern I would be very interested in a type I system.
 
In marine tanks, it's the animal fats in waste that build up on the wall of the tank. As I posted earlier, NoFlex should take care of that. But because RV toilets use so little flush water, they have a buildup in their tanks that most marine tanks don't: urine crystals (struvites). At a boat show in California this spring, I ran into a company who makes a product specifically formulated to remove and prevent struvites. He claimed to have pretty good distribution in the RV market, was at the boat show to explore marine market potential. The company is called Tech Tanks...phone is 800-625-7945. You might want to give 'em a call.

How would this product and Odorlos get along?
 
Unfortunately, there have been repeated movements to have all of Puget Sound declared a ND area. They have not yet been successful, but I am afraid that they will be soon. If it weren't for that concern I would be very interested in a type I system.

Boaters have little or no political power. Marine mammals, fish and birds poop in the water on a regular basis and in a much larger volume than recreational boaters and nobody is doing anything about this.
 
Which means the tank has to hold the sewage, not just be a pass through or a wide spot in the toilet discharge piping.

You've done an excellent job of ferreting out the legal definition of a Type III MSD (holding tank) without wandering off into the weeds that only apply to Type I and II MSD mfrs. But 33 CFR 159.53(c) only defines a Type III...not a word about devices that monitor the amount IN the Type III or the legal requirement for a means--which, btw, can include visual inspection--of knowing when the tank is at least 3/4 full. You'll find that in 33 CFR 159.83 - Tank level indicator.

Y'all might find this list of definitions pertaining to vessels that include, but aren't limited to sanitation informative kinda fun...they don't include any mention of tank level monitors either, but useful anyway 33 CFR 159.3 - Definitions.

I am still hung up on 33 CFR 159.12a(c) that discusses that a holding tank doing its job under ambient temp and pressure (typical trawler) need not met any other requirements of part 159 such as the level indicator.
 
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Boaters have little or no political power. Marine mammals, fish and birds poop in the water on a regular basis and in a much larger volume than recreational boaters and nobody is doing anything about this.

Give it time. In California we are finally getting around to regulating cow flatulance.
 
That's they type, but not the brand of the system I installed that doesn't work if sewage sticks to the inside of the tank wall.

If your waste is sticking to the wall, I would think you need to use more water when flushing.
 
Boaters have little or no political power. Marine mammals, fish and birds poop in the water on a regular basis and in a much larger volume than recreational boaters and nobody is doing anything about this.


Yup. And while it is better than it was, municipal sewage systems have put more bacteria from raw sewage overflows into Puget Sound during large storms each year than any amount from Type I MSDs.
 
How would this product and Odorlos get along?

There shouldn't be any conflict with any tank product. However, if Odorlos is doing a good job of eliminating odor out the vent by itself, it makes no sense to add another product to it. Either switch to the the Tech Tanks product, or use it only every few months to dissolve any buildup before it builds up enough to cause problems.

Peggie
http://www.amazon.com/New-Get-Rid-Boat-Odors/dp/1892399784/
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein
 
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