Depends how desperate you are, what you want to do, and what kind of boat you paddle. The lowest I've paddled the play park is 26cfs. That is too low. In the middle of winter, I wouldn't even say it is worth your time under 50. In a short boat (I paddle an S6), Library is okay down to 75. You can cartwheel, splitwheel, tricky-whu, spin, ender, side surf, etc. I have thrown a blunt (it was tiny) as low as 100. I would say 100 is actually a pretty good level for anything where you don't leave the water. If you have a longer boat (even as long as an EZ) you will be forced to stay flat under 120. I would say it is worth it. But I also live one block from Library, so it isn't very far of a trip for me. I'll be there most days through October.
"The world would be a better place if everyone kayaked."-Brad Ludden (Valhalla)
"You only get one chance to run a drop blind."-DD