Its headwaters originate 10 kilometres (6.2 mi) southeast of Lake Usborne and north of Lac Dumont in Pontiac County.

It generally flows eastward by making a large loop to the south for a distance of 85 kilometres (53 mi).

The Picanoc then widens forming Lac à la Loutre (Otter Lake) and discharges into Gatineau River at Wright (South of Gracefield municipality), in the MRC of La Vallée-de-la-Gatineau Regional County Municipality.

Thus do we find the form on a map Pikanook 1906 Wright Township, Pickanok on that of the Ministry of Mines and Fisheries of 1925 and on the Pickinock County Hull, also from 1925.

Picanoc also means a bridge, three lanes of communication and a small stream; the term was also used in the old name of the municipality of Gracefield.