Welcome to a true treasure in fishing forums. I don't have any information for you on the Clackamas. But don't give up getting your question answered. If you have time,check out the archives in that section. You will be amazed at the amount of information! You can also use the search box at the top of the page. What species are you targeting? We have numerous members in that area who can answer you,they're probably getting ready for today's fishing trip and are fast asleep.
As soon as it heats up a little, I will be up there hunting trout in my free time. I love the upper reaches of the Clackamas, and I have fished nearly every river mile accessible, pretty much from Big Bottom, above Whitefish Flats to the confluence with the Willy. There is a resident population of Speckled Brook Trout(probably introduced) up there, and they are absolutely a blast on light bug gear. Shoot me a message as the trout season heats up, ort if you need any more help with areas to fish and maybe we can pound a few classic holes above Estacada or something.
I like to float the Molalla out of Canby, and also the Clackamas is fun to bank up around Indian Henry, and all the little river pockets, and bridges, or creeks on the drive up past North Fork Reservoir are fishy, fishy. But a good trout season on the Clack is gong to get going this next month.