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Crossability verification: Baffle fishways (simulation)

For certain species, values of certain criteria are not precisely known or are subject to slight changes depending on future feedback.


Incompatible and discouraged species

Species groups 3a, 3b and 7b are discouraged for crossing baffle fishways. This leads to a warning, but does not make the pass not crossable.

Species groups 8a, 8b, 8c, 8d, 9a, 9b and 10 are unable to cross baffle fishways.

Minimum water level, in m

Water level in the pass must be greater than the minimum water level.

Criteria values for predefined species groups

From "Informations sur la Continuité Écologique - ICE, Onema 2014".

ICE group Species Minimum water level on plane and Fatou baffles (m) Minimum water level on superactive and chevron baffles (m)
1 Atlantic salmon (Salmo salar)
Sea or river trout [50-100] (Salmo trutta)
0.3 0.2
2 Mules (Chelon labrosus, Liza ramada) 0.25 0.15
3a Gread shad (Alosa alosa) 0.3 0.2
3b Shad (Alosa fallax fallax) 0.25 0.15
3c Sea lamprey (Petromyzon marinus) 0.1 0.1
4a River trout or sea trout [25-55] (Salmo trutta) 0.25 0.15
4b River trout [15-30] (Salmo trutta) 0.2 0.1
5 Aspe (Aspius aspius)
Pike (Esox lucius)
0.3 0.2
6 Common grayling (Thymallus thymallus) 0.25 0.15
7a Common barbel (Barbus barbus)
Chub (Squalius cephalus)
Nase (Chondrostoma nasus)
0.25 0.15
7b River lamprey (Lampetra fluviatilis) 0.1 0.1

Table: List of predefined values for crossing criteria of a baffle fishway