Dave --
Not a born and bred Brooklynite, but I've been here for more than40 years. I have not paddled the Gowanus Canal, though I live just a couple of blocks from it; we walk around the neighborhoods quite a bit, and often cross the canal:
But I have canoed the Bronx River a number of times with interns from my office, (portage around the Lorillard snuff mill, see the Bronx zoo bison at water's edge, cross the waste retention boom, and out into the East River and Hell Gate across from LaGuardia Airport and Rikers Island jail); I have paddled in Mill Basin and Jamaica Bay, and have been on the waters of the harbor and the East, Hudson, and Raritan rivers in a variety of boats, but not in a canoe.
I don't keep a canoe in the city -- though I have had one or two for short times as they were passing through -- too difficult to do what Deborah calls urban portaging:
This is a restoration project UFO I picked up in Pennsylvania -- too long a drive to get it to Maine in one day, so it spent a couple of nights in our Park Slope back yard. Can't keep the canoe on the street where the car is always parked, of course, and can't get it through the house at ground level, so it's up the stoop to the 2d floor, into the parlor window, through the house and out the kitchen window and down the stairs to the back yard. Then reverse the process to get the canoe out -- and this canoe weighs something over 90 pounds. Most of Brooklyn is not at all canoe-friendly (though I did see a Grumman in a Cobble Hill front yard for a while):
In the NYC Craigs list I didn't see a listing for anything that sounded like your canoe -- send me a private message with the Craigs list link.