| MacDonald River | |
| Pushpin Map: | Quebec |
| Subdivision Type1: | Country |
| Subdivision Name1: | Canada |
| Subdivision Type2: | Province |
| Subdivision Name2: | Quebec |
| Subdivision Type3: | Region |
| Subdivision Type4: | Regional County Municipality |
| Subdivision Name4: | Lac-Saint-Jean-Est Regional County Municipality |
| Subdivision Type5: | Municipalities |
| Subdivision Name5: | Métabetchouan–Lac-à-la-Croix and Desbiens |
| Length: | 8km (05miles) |
| Discharge1 Location: | Desbiens |
| Source1: | Confluence of two agricultural and forestry streams |
| Source1 Location: | Métabetchouan–Lac-à-la-Croix |
| Source1 Coordinates: | 48.3846°N 71.8899°W |
| Source1 Elevation: | 170m (560feet) |
| Mouth: | Métabetchouane River |
| Mouth Location: | Desbiens |
| Mouth Coordinates: | 48.4158°N 71.9586°W |
| Mouth Elevation: | 101m (331feet) |
The MacDonald River is a tributary of the east bank of the Métabetchouane River, flowing in the municipalities of Métabetchouan–Lac-à-la-Croix and Desbiens, in the Lac-Saint-Jean-Est Regional County Municipality, in the administrative region of Saguenay–Lac-Saint-Jean, in the province, in Quebec, Canada.
Agriculture is the main economic activity in this area; recreational tourism, second.
The surface of the MacDonald River (except the rapids) is usually frozen from late November to early April, however safe circulation on the ice is generally from mid-December to late March.
The main watersheds adjacent to the MacDonald River are:
The MacDonald River originates at the confluence of two agricultural and forestry streams, located west of Chemin du 4e rang de Métabetchouan–Lac-à-la-Croix.
From its source, the course of the MacDonald River descends on 8km (05miles), with a drop of 69m (226feet), according to the following segments:
From the confluence of the MacDonald River, the current crosses 0.8km (00.5miles) northwest to Métabetchouane harbor, to the south shore of lac Saint-Jean; from there, the current crosses the latter on 22.8km (14.2miles) towards the northeast, then borrows the course of the Saguenay River via la Petite Décharge on 172.3km (107.1miles) until Tadoussac where it merges with the Saint Lawrence estuary.[1]
The toponym "MacDonald River" was formalized on December 5, 1968, at the Place Names Bank of the Commission de toponymie du Québec.[2]