The gauge is actually on the West Branch of the Oswegatchie after the Middle Branch joins it. There is no actual gauge on the Middle Branch. Keep this in min
This is the last rapid on the river. Run left of the island and it is fairly easy boof over a hole. The hole looks fairly harmless but if you end up in the hole it can be bad. I saw a swimmer recirculated in the hole 4 times before we could rope him out.