Lake Champlaign: mast stepping

[ERGreg]

Hi; Will I need to have the mast down to transit from lake Champlaign to Sorel on the St Lawrence? via Riviere Richelieu and Chambly canal. My charts (G2) don't show bridge heights. The mast will be down to transit the Champlain canal from the Hudson R; but I would like to step and sail the lake before moving into Quebec. (plus the mast is 51' on a 35' hull; I'd like it up at the earliest convenience). thanks
Eric

[steamgoat]

You can step it at Chipman Point,about 3hrs motoring up from lock 12. Not sure what happens at the north end of the lake , Bruce.