A diver is expressing his frustration over the state of a Squamish lake after he uncovered an abundance of trash at the bottom during a recent dive.

In a video posted to YouTube, professional diver Henry Wang said he visited Cat Lake for a paid dive late last month to retrieve someone's cellphone. He's visited the lake on many occasions as he's volunteers to clean it up on an annual basis. 

"It's historically very polluted, there's always a lot of partiers here," Wang said in his video. "We've been cleaning this lake for six years now. Usually we bring a big crew."

Last September, Wang said he and fellow divers did a significant clean-up of the area. 

"We got it pretty clean," he said. "Probably not pristine, but we got it clean enough."

But when he visited the same part of the lake again on July 29, he found the bottom was littered with dozens of beer cans, at least five pairs of sunglasses, kayak paddles, a camping chair and lighters. 

All of that was found just within a small area close to a recently installed dock, which even had several empty beer cans on it when Wang was filming. 

"Just the slightest breeze comes up and everything ends up in the water," he said. 

Wang formed the volunteer group Divers for Cleaner Lakes and Oceans in 2013 when he and his friend discovered a large amount of garbage at the bottom of Port Moody's Buntzen Lake. Over a series of dives with a larger team, the volunteers eventually gathered over 1,700 pounds of trash and since then, they've continued to clean up other local lakes and rivers. 

On Sept. 20, the volunteer crew will return to Cat Lake for a "massive clean-up event."

"I don't even know what to say," Wang said in his video after his July dive. "People are just idiots."