Vincent-Lapointe, from Trois-Rivieres, Que., and Caumartin, from Otterburn, Que., held off a Hungarian team to finish first in the women's C2 500 metres.
"We were gliding so well and feeling really together," said Vincent-Lapointe. "We had a really good start and we heard the Hungarian crew but weren't letting them win."
Mark de Jonge of Halifax won a silver medal in the K1 200 metres, Mark Oldershaw of Burlington, Ont., won bronze in the C1 5,000 metres and added another bronze in the men's canoe relay with Jason McCoombs and Ben Russell of Dartmouth, N.S., and Gabriel Beauchesne-Sevigny of Trois-Rivieres.
It was the second gold in as many days for Vincent-Lapointe, who finished first in the C1 200 metres a day earlier. She now has six career world championship medals at the senior level.
It was Caumartin's first appearance at this event.
"It's a pretty incredible feeling to be a world champion," she said. "Today we had a perfect race, and I have a perfect feeling."
De Jonge finished just 0.03 of a second behind Sweden's Petter Ostrom.
"I'm happy with my result," said de Jonge. "It's a little bittersweet coming 0.03 of a second from being world champion but I'm happy with the way I raced. I executed my race plan exactly the way I wanted and I can't ask for anything better than that."
It was the first career world championship medal for de Jonge, who won bronze at the London Olympics last year.
The women's K4 500-metre crew of Emilie Fournel of Lachine, Que., KC Fraser of Toronto, Genevieve Beauchesne-Sevigny of Trois-Rivieres, Que., and Hannah Vaughan of Dartmouth, N.S., finished sixth.
Ryan Cochrane of Windsor, N.S., and Richard Dober Jr. of Trois-Rivieres were eighth in the K2 200 metres.
Adam van Koeverden of Oakville, Ont., was 10th in the K1 5,000. The four-time Olympic medallist in K1 has taken this season to focus on K2 events with Brady Reardon of Burlington, Ont.
Dartmouth's Una Lounder was 17th in the women's K1 5,000. Canada placed fifth in the men's K1 relay and eighth in the women's K1 relay.