This river flows in the territory of the sector of Gentilly of the town of Bécancour and in the municipality of Saint-Pierre-les-Becquets, in the Bécancour Regional County Municipality, in the administrative region of Centre-du-Québec, in Quebec, in Canada.

The Rivière aux Glaises owes its name to the clayey nature of its bed.

[1] The main neighboring watersheds of the Glaises river are: The Glaises river has its source in an agricultural zone in the Gentilly sector, east of the town of Bécancour.

This zone is located very close to the municipal boundary of Sainte-Marie-de-Blandford and Saint-Pierre-les-Becquets.

From its head area, the Rivière aux Glaises flows over 9.5 kilometres (5.9 mi) with a drop of 67 metres (220 ft), divided into the following segments: The Rivière aux Glaises flows onto the south shore of the St. Lawrence River, in the eastern part of the territory of the city of Bécancour.