Only one thing you've said I disagree with
Treatment devices do not introduce carcinogens(arguably or otherwise) into the environment...most use chlorine (which evaporates, leaving no lasting impact), the Lectra/San converts salt water to chlorine temporarily by charging the ions in salt water with electrical current. When the stimulus (current) is removed, the solution reverts to salt water--but salt water that now has a bacteria count of <10/100 ml. Most holding tanks, otoh, are loaded with toxic carcenogenic chemicals--formaldehyde, gluteraldehyde, quaternary ammonium compounds and who knows what in the "home brews" that some boat owners dream up. The vast majority of boat owners use Thetford, SeaLand, or other RV chemical sold at Walmart etc...you might want to visit the Thetford and SeaLand sites and read the MSDS for their tank products. So, except for the relatively small percentage of owners who use bacteria, enzyme or other all natural tank products--or only aerate their tanks without using anything in the tank (which works, btw), it's NOT a choice of a tankful of an all "natural" but aesthetically unappealing waste vs "toxic" treated waste...it's just the opposite: a choice between a HIGHLY toxic tankful and NON-toxic treated waste.As for goose poop...the person who comes up with the solution to THAT problem should win a Nobel prize! 'Cuz not only do they foul the water, but they turn the shore into a minefield that runs INTO the water every time it rains...which it does a lot in your neck of the woods. And as for the homeless who pee and poop in the streets, what makes that any different from the people on ski boats, runabouts and other open boats who just dive in when they have to go? Or the people use the "lee rail?" Both of which are legal!So Pat, you do make an excellent case for flushing toilets directly overboard instead of into a tank...one of the best against "no discharge" I've ever seen. And they they do reflect the thinking--and practice--of most boat owners. In fact, I'd estimate that there are at least as many boats on INLAND waters, hundreds of miles from any coast, who have--and use--macerator pumps to dump tanks than boats that don't. But your arguments against treatment and the lack of any real negative impact from dumping a tank just don't hold water. If you're faced with two illegal choices AND have any real concern for the environment, instead of dumping the tank, turn the y-valve between the toilet and the tank and flush the toilet directly overboard...send the tank contents to the sewage treatment plant so THEY can dump it into the water in the next spill.
