The Rivière d'Aulnage is a tributary of the rivière des Sept Îles, flowing on the north shore of the Saint Lawrence river in the municipalities of Saint-Léonard-de-Portneuf and Saint-Basile, in the Portneuf Regional County Municipality, in the administrative region of Capitale-Nationale, in the province of Quebec, in Canada. The upper part of the Aulnage river flows mainly in the forest, descending the Montagne de Sainte-Angélique; the lower part is mainly in agricultural area. For example, forestry and agriculture are the main economic activities in this valley. This valley is served mainly by the chemini of rang Sainte-Anne and by the rue Sainte-Angélique which becomes towards the north the chemin du rang Sainte-Angélique. The surface of the Aulnage river is generally frozen from the beginning of December to the end of March; however, safe circulation on the ice is generally from late December to early March. The water level of the river varies with the seasons and the precipitation; the spring flood occurs in March or April.
Geography
The Aulnage river takes its source at the confluence of three forest streams on the Sainte-Angélique Mountain, in Saint-Léonard-de-Portneuf, near the northern limit of Saint-Basile. This source is located under Hydro-Québec's high-voltage lines at northwest of the mouth of the Aulnage river, at north-west of the village center of Saint-Basile, north-west of the mouth of the Rivière des Sept Îles and north of the mouth of the Portneuf River. Course of the rivière d'Aulnage From its source on the Sainte-Angélique Mountain, the waters of the rivière d'Aulnage flow over:
to the south down the mountain, then south-east into the agricultural plain, passing by Saint-Basile Airport, up to the street bridge Sainte-Angélique;
towards the south-east by collecting several small agricultural streams, up to its mouth which flows into the rivière des Sept Îles, at the north of the village of Saint-Basile.
The Aulnage river flows on the northwest bank of the rivière des Sept Îles. From the mouth of the rivière d'Aulnage, the current descends on to the south taking the course of the Sept Îles river, then on towards the southwest taking the course of Portneuf River by winding through the plain of the St. Lawrence, to the north shore of the St. Lawrence River.
Toponymy
In Europe, an alder grove means a forest-type vegetation where predominantly the alder, a tree of the family Betulaceae. In eastern Canada, an alder grove can be both a forest and a wetland. Two types of alder are present on the territory, the crested alder and the rough alder. These two species are not found in the same habitat. The first is in a dry environment, thus designating a vegetation of forest type and the second in a wet environment, therefore designating a vegetation typical of a wet environment. Aldering means the action of cleaning an alder grove. The toponym "Rivière d'Aulnage" was formalized on August 17, 1978 at the Place Names Bank of the Commission de toponymie du Québec.