Gauge Description:

Flows are the sum of USGS South Fork Payette near Lowman plus Deadwood River.
 

After the Deadwood river is shut off, the Canyon flows can be in the 345 cfs range, which is generally too low for rafts, but still some creeky fun for kayaks. 
For example, in 2015 the Deadwood stepped down from 1000 to 900 on August 25, then to 700 on August 28, then down to 50 on August 31. That puts the Canyon flow around 345. 

Gauge Information

Name Range Difficulty Updated Level
Payette; South Fork below Deadwood Confluence
virtual-49596 1500 - 2500 cfs III-IV 00h33m ~ 3085 cfs (running)
gauge class Below 2500 is more manageable.

gauge graph
RangeWater LevelDifficultyComment
330 -5000 cfs barely runnable-high runnable III-IV gauge is important or has warning Below 2500 is more manageable.
1500 -2500 cfs med runnable-a bit pushy runnable III-IV gauge is important or has warning

Reports give the public a chance to report on river conditions throughout the country as well as log the history of a river.