The main hydrographic slopes near the "Port-au-Saumon River" are: • North side:
Port au Persil River,
Noire River (Charlevoix),
Port aux Quilles River,
rivière de la Baie des Rochers,
Saguenay River;e • East side: Port-au-Saumon Bay,
St. Lawrence River; • South side:
Malbaie River,
Comporté River, Pednaud Creek,
Loutre River (Rivière du Gouffre),
Mailloux River,
Jean-Noël River; • West side:
rivière Noire Sud-Ouest,
Jacob River,
Snigole River,
Malbaie River. The Port-au-Saumon River has its source at "Lac du Port-au-Saumon" (length: ; altitude: ) which is clover-shaped deformed and in forest area. The resort is developed around the northern appendage of the lake. The mouth of the lake is at the bottom of the eastern appendage. From the mouth of Port-au-Saumon Lake, the course of the Port-au-Saumon River descends by traveling according to the following segments:
Upper part of the Port au Saumon River (segment of ) • easterly along the south side of Port-au-Saumon Lake Road, then south-east, winding to the confluence of the Lake of Port au Saumon (coming from the north); • southeast winding to a creek (coming from the west); • south winding to a creek (coming from the west);
Lower part of the Port au Saumon River (segment of ) • northeasterly under the Sainte-Anne Rang Road Bridge, forming a southerly curve across a series of rapids over this segment to the bridge of the
Route 138 (Malcom-Fraser Boulevard); • southeasterly crossing a series of rapids to the east shore of Port-au-Saumon Inlet which is interelected in the
Gulf of St. Lawrence. Sabere and Camarine Islands guard the exit of this bay. ==Toponymy==