We have a 43 Trawler. We are on the Loop.
I had done a fair amount of research into composting toilets due to the plethora of areas we were going to be going thru which included many NDZ. Lake Champlain itself is 1 big NDZ.
After that research I removed the toilet in our forward head and replaced it with an Air Head, again after reviewing the major choices.
With all the guffaws and wisecracks, hold on to your asses as with all of the algae blooms occurring, who do you think will get the brunt of the kickback? It won't be the farmers, landscapers or others using fertilizers, pesticides, manure or other items that are running of into the rivers, lakes and streams, it will be the boater with his toilets streaming crap into the water. Wait & see.
The result will be no overboard discharges. It will be no holding tanks that can be discharged into the water. It will be nothing short of a plastic bag which will have 'stations' at marinas where specific dumpster like collection bins are.
A possible alternative could be a composting toilet.
We still have a raw water toilet in our aft head which is connected to a 2 way valve. One setting will direct the effluent to our 75g holding tank. The 2nd setting will direct it to a Raritan Type 1 MSD which treats and discharges overboard. We have the valve 'locked' in the holding tank position.
In my research there were locations that would require any holes in the hull which have an upstream source of effluent would need to be plugged. Fortunately, most of those holes are below the waterline, so I don't know how they would ever check, UNLESS, they board you and check your plumbing, which is why I have my 2 way locked. No use debating the boarding. By the time you might win in court, you own more on storage than you paid for the boat.
Dealing with effluent is a crappy job, pun intended, as there are NO laws, rules or regulations which apply to all municipalities, parishes, counties, state or federal areas which are all the same. On top of that, states were given, as I understand it, the right to establish NDZ (No Discharge Zones) which have rules which vary state to state as well.
Due to the above, I don't believe that I lowered my resale value, which I don't count on anyway as my mate has orders to perform a Viking funeral for me at the appropriate time, because we have a composting toilet. We may have actually raised it as the new owner, of the ashes, wouldn't have to do the job themselves of putting in a composting toilet.
But all that said, I will probably put in a new toilet in the aft head and replace it with a Raritan toilet which uses raw water to flush. Having the 3 options provides for almost all contingencies.
As I said, we put in an Air Head, they are all doing the same job, but after talking with the owner and with the support he offered, we thought Air Head was the best choice for us, and part of the installation was to provide for a fan to move air through the 'system'. Our forward head is located athwart ship from the galley with the wiring closet. It was an easy setup to pass the air hose through the wiring closet and out the side of the deckhouse right under the shore power receptacles.
BTW, we have a similar set of rules for our guests as well; Rule #1 - Everyone must sit. No exceptions. Rule #2 - If it didn't come out of you, it doesn't go in the toilet. BTW, these rules are for both heads should a guest use our aft head.
My mate is who wanted the composting toilet, so our deal was I put it in and she takes it out. I think that the urine bottle isn't too heavy that she has trouble carrying it. AAMOF, at times she has carried 2 at 1 time.
An interesting additional thought to consider. I had read that in some areas you could pee over the side (be careful about doing this in a marina & USCG records show a good number of those who drowned, had their fly open, food for thought) but you can't dump a bucket of pee over the side. We bought 2 pee bottles when we bought the unit.
In closing I saw that the Head Mistress has opined some of her thoughts. Listen to her, she knows this area, VERY well and is providing information you should be listening to. Thanks Peggy.