Flow: 17.5 cms: rising
The online gauge is located in the town of Petawawa and is not related to the visual gauge on the highway bridge. Rain in Algonquin park will not affect the Pet town gauge for a couple of days, so there seems to be 2 day lag time between the online gauge and the actual level on the upper Pet.
Especially at high, spring flows, the above gauge reading is probably best considered a rough estimate. The 2 day lag time could mean a difference, up or down, or 50 cms
The Upper Pet is fairly steep section with 26 rapids varying from class 3-5. It varies in nature from a technical run at flows from 25 cms down, to a bigwater run at higher levels.
Low: 13 cms (2.3 online gauge)
Ideal: 25 cms and up (2.45 online gauge)
High: Unknown. It does get significantly harder at flows above 40 cms, with more of a bigwater feel.
From ice-out to freeze-up. Peak flows, averaging over 100 cms, are in April/May. Lowest flows are in September.