Ryker Gamble, 30, Alexey Lyakh, 30 and Megan Scraper, 29, were hiking with friends in Shannon Falls Park, just north of Vancouver, when the accident happened.
Royal Canadian Mounted Police said the group had been swimming in one of the pools at the top of Shannon Falls - the third highest waterfall in British Columbia - when they slipped and fell 30m (98ft) to their death.
The Vancouver Sun reports that all three were swept away after Gamble and Lyakh went to the aid of Scraper who had got into trouble after tripping and falling.
Their bodies were later recovered by a search and rescue team from a pool below.
Gamble and Lyakh were two of the co-founders of a Vancouver-based collective - High on Life SundayFundayz - who regularly posted videos of their extreme adventures around the world.
Scraper, who also posted videos of her adventures - one of which showed her sitting on high metal train tracks, tens of meters above the ground - was the long-term girlfriend of Lyakh.
The members of the group all aged in their 20s and 30s met at high school, and posted weekly videos "to inspire our viewers to get out and explore the world".
Their channel has over 500,000 subscribers, while their Instagram account has over a million followers.
In 2016, Gamble and Lyakh were banned from a host of US national parks - along another group co-founder Justis Price Brown - after walking on a sensitive hot spring in Yellowstone National Park.
They also received one-week jail sentences and received fines totalling $5000 (£3,770) for a series of violations.
The remaining members of the group made an emotional tribute to their friends in a video on the High As Life YouTube page.
Describing them as "three of the warmest, kindest and most driven and outgoing people you could ever meet", the group fought back tears as they talked about the "pain and the devastation" of losing their friends.
The video has been watched more than 60,000 times in less than 24 hours.
Ryker Gamble's girlfriend posted an emotional tribute to him on her Instagram page, sharing the words of storyteller Heather Obscura as a way of expressing her grief.
A memorial fund page has been set up for friends and families of the three vloggers to help with funeral costs.
The group has also asked fans to share social posts showing how High On Life inspired them using the hashtag #HOLinspired, which they say they will use to "collect all of your love and thoughts in one place".