The Dranse de Morzine is consequently considered its tributary, according to Sandre, the French National Service for Water Data and Common Repositories Management.

Its discharge was observed for a period of 97 years (1906–2003) in Reyvroz, a locality in the department of Haute-Savoie situated on the southern bank of Lake Geneva at the same elevation as its outlet.

[3] The drainage basin for the river is in its totality 495 square kilometres (191 sq mi), which is not quite three times the surface area of the city of Paris.

These accompany average monthly discharges of around 30 to 40 cubic metres (1,100 to 1,400 cu ft) per second from April to June (the maximum being reached in May).

The runoff curve number for its drainage basin is 1,285 millimetres (50.6 in) annually, which elevated, is three times greater than the average for all of France.