1. Hans-Petter Fjeldstad
To-way migration for Atlantic salmon past hydropower intakes – New research and technologies
October 7, 2016
Hans-Petter Fjeldstad
SINTEF Energy
In collaboration with:
-Torbjørn Forseth and colleages at NINA, Norway
-Henrik Baktoft, Danish Technical University
-Knut Alfredsen, NTNU, Norway

2. The Atlantic salmon
Illustration: NASCO

3. Upstream
migration

6. Downstream
migration

7. Foreløpig resultat 2008
Safe bypass
Lære
Intake

8. Challenge
Safe road
2003: 10 %
Goal: 90 %
Wrong route

9. Fine mesh racks
Images from Olle Calles, Karlstad University

10. Conducted studies When do smolts migrate?
Where do the smolts migrate under a normal production regime (without flow mitigations)?
Can we influence the migration route through hydraulic and physical measures (strobe lights/ floating boom)?
3D Telemetry linked with hydraulic modelling

11. Telemetry Experiments
Tagging of 450 smolt ( )

12. Smolt timing model based on catches from an upstream rotary screw trap
Observed smolt catches
Model predictions
R2 = 0.60
Fjeldstad et al., 2012

13. Impacts of increased bypass flow
54%
64%
11%
Without targeted flood spill
With extra bypass spill

14. Nightly reduction of power production seems to be successful
69 %
2003, 2004 og 2008
Day (8am – 9pm)
Night (9pm-3am)
Morning (3am-8am)

15. Strobe lights Significant impact in dark hours

16. Surveying (RTK GPS combined with soundings and accoustic velocity measurements)
IEA Hydro Dec 2013

17. Topographic model
13.5 m

18. Water velocities
Intake area

20. Details from the intake area

22. 1. 2D and 3D positioning using 200 kHz acoustic telemetry with wireless hydrophones (Lotek).  2. Practically unlimited number of tags can be in the system at any time.  3. Small tags (15x6.5 mm) can be used with small smolts, and with a burst interval of 5 s last for 45 days. 

23. Hydrophone allignment at intake

26. Alternative bypass corridors
Photo: Anders Lamberg

27. Repulsing measures LED-lights and infra sound (5-16 Hz)
Electric fields

28. Thank you!