I'm generally pretty anti-discharge, but given that no one is swimming in the winter and the history
of combined sewer overflows in NYC
, I'd install a type 1 MSD and not worry about it in the winter.
For those that do not know about combined sewers, sanitary waste and storm water
run in the same pipe. At the end of the line, there is a sump pump that sends the waste to the treatment plant. However, because the plant can only handle so much volume, when it rains more than a sprinkle, the waste overflows into the river. This is not an accidental spill, this is normal and designed for. On the average, a type 1 MSD is going to outperform a heavily loaded combined sewer.
I would also use the marina facilities as much as practical, so the MSD discharge will be limited.