My F-31 Fisher map shows a dam at the northern end of the channel on the north shore of Lake 2, between lakes 1 & 2. My F-4 map does not. Does that dam exist, and, if so, is it possible to portage around?

here is an account from someone thats been at it .(copied from another site)

there are no portages, the bushwacking is a bit difficult, the places where you need to get out and get around are nasty to land on, and the lower portion is an absolutely nasty bit of ankle-twisting agony.
The first riffle leaving Lake 2 is an old logging-era dam that had a flume. If you study it carefully from shore, you might well conclude that it is easily runnable. What you failed to see are the massive spikes placed in parallel lines, which used to hold the flume in place. Hit it dead center - you make it. Off by a hair - goodbye structural integrity of the watercraft.
Further downstream is a pretty little waterfall that cannot be run. There's no way around the right side, leaving you your only option of getting out on the left above the falls. If you're good, you will successfully make the landing on the slippery boulders, and then try to clamber up the steep slope, and back down an even steeper ledge rock with NO relief to the slope where it meets the water. Don't slip.
The final indignity is the lower portion just above Lake One, which most of the year is a field of rounded boulders, which you will need to carry your craft over. The waters drift through the delta of boulders in tiny rivulets - none of which offer a way to float.
Upon reaching the bottom, you have to ask yourself what possessed you to do it in the first place.
Bottom line for the outfitters that if you do screw up on that route - and a few have - recovery of their gear is going to be a nasty business (which is how I got roped into doing it the first time).

as kev is saying, don't even consider it.it's a cool place to hang out from the top side.plus a nice paddle up from lake 2 down below.

thanks for the info,think i'll skip it go through lake one proper

I signed up here after being a lurker for a few years.

I saw that Lake Two's ordeal that is described above is now labeled as "dam." I got roped into this once (not literally) and I thought I'd share my experience to echo just how awful it is.

The description above is correct. You can, with difficulty, bushwack around the really-not-great part: https://streamable.com/iofagr that's just part one though.

You'll descend that hill with your canoe, lowering it gracefully down 50 feet of a 60-degree ramp. On that decline there's a rock that looks like a tooth right in the middle. You may slip and land square on your back, only to be forever thankful that you had both PFD and pack on, otherwise you're sure you would end up paralyzed.

The rest of the way is less exciting in comparison. It's beautiful back there, but at a cost. Maybe if I had went in September after a month of no rain I could have enjoyed it. It was stressful, particularly because my paddle partner was inexperienced. (It was there idea to take this "shortcut.")