For the last 30-40 yrs., discharge of poop is illegal in the fresh water
lakes, the "Great Lakes," and for good reason, they constitute the fresh water supply for many people.
Saltwater --maybe the word is biology-- is different. Saltwater fishes consume our effluent gladly. So the Tamar is a muddled situation. Preferable, I think, ultimately, although Jim might not concur, I think it is best to not discharge where there is not plenty of oxygen exchange, but other than that, the fishies do take care of our s--t. This is an extremely unpopular view in the US, but in some places in Mexico
, the grunts wait for the morning discharge, and you hear them talking about it, like, "when are they going to make breakfast for us?" Sorry, guys, but this is true. No offense intended. Oddly, if we discontinue discharge, the fish
population will move elsewhere.
If you've ever considered eating crabs, they, too, change excrement into lovely flesh to eat if you're not a vegetarian, or have religious rules against eating scavengers.