Before I forget, I wanted to post my experience sailing up the St. Lawrence. This may be of help to anyone sailing up the St.Lawrence and “googling” for more info. It can be hard and slow working against the 1-4kt currents and prevailing SW winds in a boat that does ~5-6kts. Fortunately, the flood tide reverses the current for a two periods each day and if you’re willing to sleep/wake according to the tide cycle. This can be a great help from Rimouski to Portneuf.

Tip #1 – HUG THE SHORE. (unless playing the flood tide) Staying as close as possible to the shore, in shoal water and out of the main channel, drastically reduces the current. Sometimes the current even eddies and runs contrary near shore.

TIp #2 – Get a copy of “Atlas of Tidal Currents (St. Lawrence estuary)” or use their website: www.slgo.ca/ocean. I also highly recommend the cruising guide  St. Lawrence River and Quebec Waterways 2nd edition

My route: I left Rimouski 2 hours after high tide heading for anchorage in Cacouna harbour, 55nm. It took 12 hours. I left Cacouna 2 hours after low tide and got to Cap a l’Aigle in 6 hours, ~30nm. It’s possible to make it from Cap a l’Aigle to Quebec City, ~70nm, in one shot if you leave an 1 hour before low tide, hug the shore, and take the south channel into Quebec. I got caught in the awful waves created when a strong SW wind blew against the flood current in the south channel. Avoid this situation at all costs!I Left Quebec City 2 hours after low tide to pass under bridge 3 hours after low tide when flood current arrives there, made it to Portneuf in 5.5hrs, ~35nm. Left Portneuf 2 hours after high tide to make it through the Richelieu rapids. It took 8hrs to Trois Rivieres. Trois Rivieres to Montreal took 19hrs, no more tide to help and the current averages 1.5-2kts. Zeelandia motors at 5-5.5kts through the water.