Handling gray and black water on Loop

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Joined
Jul 3, 2016
Messages
1,455
Location
Sandusky Bay
Vessel Name
Escape
Vessel Make
Mariner 37
Okay, total noob question here. I'm very familiar with land-based RV sewage systems. Two separate tanks for gray and black water that dump by gravity at usually free dump stations. I believe I have read that gray water can go directly overboard along most of the Loop. Really? So all those boats moored at Put In Bay and Charlevoix are dumping dishwater and shower water straight to the lake? That would certainly simplify the plumbing issues.

And I get that gravity won't work when you have to drain "up" to the sewer connection. Seems like macerater pumps would be a regular maintenance issue. How often should one expect to rebuild, clean out or replace one's macerater pump?
 
And I get that gravity won't work when you have to drain "up" to the sewer connection. Seems like macerater pumps would be a regular maintenance issue. How often should one expect to rebuild, clean out or replace one's macerater pump?

Yes, grey water goes overboard. The dock sewer connection for black water sucks. I carry my own screw-in adapter for the access port on the boat as a few places don't have the correct one. Make sure your vent on the tank is clear. Macerater is not needed on the Great Lakes or rivers.
 
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Ah-hah, so the sewage "dump station" has its own vacuum pump that sucks the black water out? Makes sense. Is that a fee service?
 
Yes, vacuum pumps. $5 on Lake Michigan. Sometimes waived if you buy a measureable amount of fuel...or if they're understaffed and let you do it yourself.
 
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You obviously don't have a boat or all of this would be (mostly) plain. Here is a summary:


Virtually every where a boat can go it is ok to dump grey water, so boats are plumbed so that sink and showers go over board.


NO untreated black water can go overboard anywhere inside the 3 mile coastal limit. Outside the 3 mile limit is the only place where you can use a macerator to dump your holding tank. Otherwise it is sucked out at a marina facility.


Chemical treatment, ie Saniflush and Puriflush can be used in many coastal areas. Some areas are designated no discharge zones and no black water can go over board no matter if treated or not.


So all cruising boats have holding tanks and some have chemical treatment that is used in areas that allow it.


The regs require that any valve from the toilet overboard, typically the discharge from a macerator pump, be "permanently locked". This has been interpreted as anything from a real lock to a wire tie to taking the handle off of the valve. In really anal systems like Lake Champlain, I would use a lock or remove the handle.


So, as you can see, macerator pumps are mostly irrelevant if you want to follow the law ;-). They do fail, but not routinely. Often you can turn the slotted shaft with a screw driver and free them up.


Peggie, please correct me if I am wrong!


David
 
Good overview....

also, some newer boats dont have seacocks on overboard discharge that can be "locked".

They just have a switch with also a keyed switch outside of the head....seems to be accepted.
 
Good overview....

also, some newer boats dont have seacocks on overboard discharge that can be "locked".

They just have a switch with also a keyed switch outside of the head....seems to be accepted.
I wouldn't call my boat (2000) "newer", but that's what it has - just a key switch. I installed it myself replacing an ordinary push button switch. I keep the key hidden, not in the switch.

There's no valve in the discharge plumbing.
 
We haven't encountered a marina yet on the loop without pump out ability. I'm sure there are some but we haven't landed at any of them.
 
Thanks folks. Lots to learn. My mission is to get as much of it figured out as I can before buying a boat.
 
there is some great info in the responses to this thread and I learned something about which I had been thinking about.

Thanks everyone!

Ch
 
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