Took this woman down the canyon on our first date. Been married 25 years now. It was the first day of spring 1982 and had just snowed 4 inches that night. It was all mud, slush and the stream was moderately full. We somehow descended without gear. She freaked out a few times but I talked her down. I recommend talking a rappel rope for maximum enjoyment.
I'll definitely go back sometime. done with Theron as a virgin to colby. Very pretty route.
I barely had enough gear to get down the section described in this canyon page. Brennen's chapter on Colby Canyon was prepared in 1999. He suggests there is only one place where you really need gear. I found four places where I had to rappel; couldn't find a way around the waterfall and couldn't down climb safely without protection. But it's a pretty little canyon.