From some one who knows Barrier Dam (look for the guy with the "fishin' sombrero" with a real big hook in it:

In spite of the fall chinook run being spotty (1 to zero "bright" fish in daylight hours total for all fishermen) & every other evening right at dark, a bright one or two usually gets picked up, The few "bright" ones are getting picked up in the fast water while all fish from the middle through out the tail out are black & sore...

Saw 3 silvers on ropes for this weeks effort, got one (a 4 -5 lb'er myself on Sunday), none when the sun is high, either right after dawn or right at dusk,

in spite of the few good few fish being caught, the place is pretty crowded on the week ends & now week days too. the time when the sun is up is reserved for untangling lines, haggling over space, reeling in & waiting while another black beauty gets drug past you by the tail, & enjoying/suffering through amatuer hour, the pay off is @ dawn/dusk

so bring patience & a willingness to help the inexperienced & you'll probably get a fish & have a decent time doing it...