Measurements of the river flow were taken at the Oletta [Malpergo] station from 1972 to 1996.
The watershed above this station covers 68.6 square kilometres (26.5 sq mi).
Annual precipitation was calculated as 266 millimetres (10.5 in).
The average flow of water throughout the year was 0.577 cubic metres per second (20.4 cu ft/s).[3]
Average flow (cubic meters per second) by month for the period 1979 to 1999[3]
Month
Flow
Jan
1.010
Feb
1.260
Mar
1.200
Apr
1.150
May
0.577
Jun
0.208
Jul
0.076
Aug
0.039
Sep
0.079
Oct
0.151
Nov
0.579
Dec
0.651
Tributaries
The following streams (ruisseaux) are tributaries of the Aliso, ordered by length, and sub-tributaries:[1]