'White River'; formerly designated "rivière Saint-Wenceslas") is a watercourse on the South shore of St. Lawrence River, in the administrative region of Centre-du-Québec, in the province of Quebec, in Canada.

This river flows in the regional county municipalities of: The Blanche River flows northward mainly in agricultural (or forest, in places) territory on the south shore of the St. Lawrence River.

[1] A marshy area (2.3 kilometres (1.4 mi) by 1.7 kilometres (1.1 mi)) straddling the limit of the municipalities of Sainte-Eulalie and Daveluyville (Defoy sector) constitutes the head of the waters of this river.

This area is located northeast of Saint-Samuel-de-Horton, southwest of Daveluyville, east of Sainte-Eulalie and south of autoroute 20.

[2] The toponym "Rivière Blanche" was made official on November 27, 1979, at the Place Names Bank of the Commission de toponymie du Québec.