The teen's best friend, 17-year-old Catherine Desautels, was able to make it to safety after a harrowing two hours in the rough, frigid water.
Cpt. Harry Waddup of the Richelieu—St-Laurent police said the underwater search will make up the bulk of the activity in the bid to find the missing man today.
"The scuba diving team is going to continue exactly where they left off last night," he said.
"They left a buoy exactly to indicate where they're up to, and they're going to continue with the search today."
Waddup said searchers using jet skis will also be taking part.