The upper part is mainly accessible by the chemin du rang Saint-Régis.

The surface of the Esturgeon River (except the rapids areas) is generally frozen from mid-December to the end of March; however, safe circulation on the ice is generally done from the end of December to the beginning of March.

The water level of the river varies with the seasons and the precipitation; the spring flood occurs in March or April.

The Esturgeon River rises at the confluence of two agricultural streams.

This confluence is located 0.9 kilometres (0.56 mi) south of the village center of Saint-Isidore, 7.1 kilometres (4.4 mi) to the East of the course of the Châteauguay River, at 9.4 kilometres (5.8 mi) north-east of the confluence of the Esturgeon river and the Châteauguay river, at 13 kilometres (8.1 mi) southeast of the mouth of the Châteauguay river.