Talks provided at the Scottish Fisheries Co-ordination Centre/Institute of Fisheries Management MAPPING FISHERIES workshop in Edinburgh on March 1st-2nd 2016

1. Hydraulic Habitat Modelling
and Mapping
Dave Mould

2. Structure
• What is hydraulic habitat modelling and mapping?
• Hydraulic modelling (in 2 slides……)
• 3 case studies
– As part of the design process
– Investigation tool to build evidence
– Impartial appraisal
• Summary

3. Hydraulic habitat
The combination of river depth, velocity and substrate determines the
available physical habitat for aquatic species.
Therefore, hydraulic models can then be used in combination with
knowledge of the habitat requirements of species/life stage of interest
to determine habitat availability. Can also inform on sediment
dynamics.

4. 1D modelling
Max vel
Island

5. 2D modelling
APR Project 15. Two dimensional modelling in Urban and Rural Floodplains

6. Case study 1 - Design

7. Case study 1 - Design

8. Case study 1 - Design

9. Case study 1 - Design

10. Case study 1 - Design

11. Case study 2 – Evidence
EA science project SCSC0120077

12. Case study 2 – Pershore weir

13. Case study 2 – Evidence
Q95 Depth. On-weir HEP Q95 Depth. Depleted reach Q95 Velocity. On-weir HEP Q95 Velocity. Depleted reach
Difference = post installation minus pre installation.

14. Case study 2 – Evidence
Q20 Depth. On-weir HEP Q20 Depth. Depleted reach Q20 Velocity. On-weir HEP Q20 Velocity. Depleted reach
Difference = post installation minus pre installation.

15. Case study 3 - Appraisal
Pool and run
Shoulder
Vegetation management

16. Case study 3 - Appraisal

17. Case study 3 - Appraisal

18. Case study 3 – Pool and run
Pre change adult Brown Trout habitat Post change adult Brown Trout habitat
Pre change Brown Trout spawning habitat Post change Brown Trout spawning habitat
Run
Pool
Run
Pool
Run
Pool
Run
Pool

19. Case study 3 - Shoulder
Pre-change 0+ Cyprinid habitat Post-change 0+ Cyprinid habitat

20. Case study 3 – Veg removal
Pre-change 0+ Cyprinid habitat Post-change 0+ Cyprinid habitat
Pre-change Brown Trout spawning habitat Post-change Brown Trout spawning
habitat

21. Case study 3 – Crisp summary
Total Habitat Suitability (THS)
Q95 Q70 Q50 Qmean Q10
Adult BT 2665 4085 4495 4761 5178
1+ BT 2685 3689 3939 4318 5247
0+ BT 4798 5011 4559 3913 2197
BT
Spawning 2791 3523 4202 4698 5360
0+ Cyp 862 1568 1596 1607 2019
Habitat Quality
Q95 Q70 Q50 Qmean Q10
Adult BT 26 32 35 36 37
1+ BT 26 29 31 33 38
0+ BT 47 40 36 30 16
BT
Spawning 27 28 33 36 39
0+ Cyp 8 12 12 12 15

22. Summary
Pros Cons
Across whole flow regime and range
of species/life stages.
Cost of survey data vs scale of the
modelling
Spatial & crisp outputs Often limited knowledge of
requirements of many species
Results in a data poor situation Uncertainty in model results
Play tunes with model topography
Optimisation of designs