Dozens of fun-loving commuters in Colorado took an alternative, green route to the office on 14 July – floating down the Boulder river to work.

Workers came in their work clothes, while others were in their swimwear, to gathered for the eighth annual Tube to Work Day event. The idea was cooked up by two friends in 2008, said Jeff Kagan, one of the original tubers.

"This started with two strange guys, myself included, who wanted to tube to their office which was just a couple of hundred yards from the creek, it took eight years but now we got a big crew and we are going to keep growing."

"I've watched it over the last few years, and it's just very fun, it's very fun goofy idea," Pamela Bondurest said.

The group of around 50 floated amid cheers in an armada of floating vessels in different shapes and sizes. Halfway to work, a breakfast station was set up – offering doughnuts and coffee.

"It's just a great way to start the morning get a good adrenaline rush before getting into work. I had to take the rest of the suit off so I can warm up from the sun, need to absorb the rays for a second," commuter tuber Jordan Wilsted said.

"The traffic might have been worse here than it is down I-25 on the way down to work, but it's still worth it, it's much better than being in a car," Wilsted added.

The commuter tubers are hoping to promote alternative, environmental friendly ways of getting to work. Bike to Work Day, is another activity Boulder's environmentalists annually host.