Environmental impact of
Belgian offshore wind farms:
Learning from the past to optimise
future monitoring programmes
Royal Belgian Institute of Natural Sciences
Management Unit of the North Sea Mathematical Models
Steven Degraer
Delphine Coates, Jan Vanaverbeke, Jan, Reubens, Magda Vincx, Eric Stienen, Nicolas Vanermen, Kris Hostens, Sofie
Vandendriessche, Jozefien Derweduwen, Robin Brabant, Bob Rumes, Marisa Di Marcantonio, Alain Norro,
Francis Kerckhof, Jan Haelters, Laurence Vigin, Ilse De Mesel
In collaboration with:
Ghent University, Marine Biology Section
Research Institute for Nature and Forest (INBO)
Fisheries Research Institute (ILVO-Fisheries)
OFFSHORE WIND FARMS IN BELGIAN WATERS
C-Power
• 54 wind turbines (WT); total capacity: 325 MW
• Phase I: 6 WT (5 MW, gravity base foundations) operational since 2009
• Phase II: 48 WT (6 MW, jacket foundations) construction ongoing
Belwind
• 110 WT of 3 MW; total: 330 MW
• Phase I: 55 monopile WT + 1 OHVS
operational since 2010
• Phase II: 55 monopile WT in 2014
Northwind
• 72 WT of 3 MW; total: 216 MW
• Construction ongoing
Belwind
Northwind
Four more domain concessions
• 210-294 WT; total: 1243-1634 MW
• Two project: environmental
permit granted
C-Power
Once all constructed...
• Total surface area: ± 210 km²
• Number of turbines: 446 - 530
ENVIRONMENTAL IMPACTS EXPECTED
GUARANTEES FOR ECOSYSTEM INTEGRITY
Mandatory monitoring programme to ensure...
• possible mitigation or halting of activities
• understanding of impact processes to support future policy and management
Environmental issues to consider
• Underwater noise
• Hydrodynamics and sedimentology
• EMF
• Hard substrate epifouling organisms
• Hard substrate-associated fish
• Soft substrate macrobenthos
• Soft substrate epibenthos and fish
• Seabirds
• Marine mammals (focus: harbour
porpoise Phocaena phocaena)
• Social acceptance
Sula bassana
THE CHALLENGE...
Baseline and targeted monitoring
Baseline monitoring
• Focus on a posteriori resultant effect
quantification
• Site-specific
• Observing rather than understanding
impacts
• Basis for halting activities
Phocoena phocoena
Balanus perforatus
Targeted monitoring
• Focus on cause-effect relationships
of selected, a priori defined impacts
• From observation-driven to
hypothesis-driven monitoring
• Understanding rather than observing
impacts
• Basis for mitigating activities and
future policy
Gadus morhua
SELECTED ENVIRONMENTAL IMPACTS
Phocoena phocoena
Aerial survey results
Pile driving disturbance of marine mammals
SELECTED ENVIRONMENTAL IMPACTS
Average relative change (%)
Pile driving disturbance of marine mammals
150
During piling
One day after
cessation of piling
100
50
0
-50
Decrease of total
population size
-100
1
11
21
31
Distance from piling location (km)
41
51
SELECTED ENVIRONMENTAL IMPACTS
Mean density (ind./km²)
Attraction and macro-avoidance of seabirds
AVOIDANCE
ATTRACTION
Before
Reference area
After
Impact area
• Significant effects were found, but...
• Detection power is low !
• Long-term monitoring needed to
quantify true effect
SELECTED ENVIRONMENTAL IMPACTS
Attraction of fish
Gravity based foundation
Number of detections
Small-scale distribution of cod (Gadus morhua)
pouting
Jassa species
Distance from foundation (m)
• Attraction of fish
– up to 29.000 individuals of pouting (Trisopterus luscus) per wind turbine!
• Attraction-production hypothesis
– Hard substrate epifauna is an important food source for pouting
SELECTED ENVIRONMENTAL IMPACTS
1.0
Artificial hard substrate and epifouling invertebrates
262
Gravity based
foundation
succession
1033
0.5
1048
Winter
1271
1369
105
976
711
1090
635
678
900
0.0
811
1504
510
798
412
NMDS2
1074
762
399
Summer
1100
482
440
837
556
394
738
-0.5
199
276
247
-1.0
176
145
-1.0
-0.5
Monopile
foundation
0.0
summer
autumn
w inter
spring
0.5
Surface area
GBF: ± 3000 m²
monopile: ± 500 m²
1.0
NMDS1
Epifauna on new hard substrates (i.e. foundations) in a sandy environment
– ecological succession to a rich and diverse community (101 species)
– Equilibrium reached after 2 years ?
– YET: poor representation of what may be expected on natural hard substrates
SELECTED ENVIRONMENTAL IMPACTS
Artificial hard substrate and non-indigenous species
**
**
*
**
*
Megabalanus coccopoma (Darwin, 1854)
Balanus perforatus Bruguiére, 1789
Telmatogeton japonicus Tokunaga, 1933
Elminius modestus Darwin, 1854
Jassa marmorata (Holmes, 1903)
Mytilus edulis (Linneaus, 1758)
Semibalanus balanoides (Linnaeus, 1758)
Balanus crenatus Bruguiére, 1789
Patella vulgata Linnaeus, 1758
Hemigrapsus sanguineus (De Haan, 1835)
Crassostrea gigas (Thunberg, 1793)
Littorina littorea (Linnaeus, 1758)
Balanus improvisus Darwin, 1854
Emplectonema gracile (Johnston, 1873)
Emplectonema neesii (Örsted, 1843)
Pleioplana atomata (OF Müller, 1776)
Eulalia viridis (Johnston, 1829)
Year
One
C
S
S
A
C
F
C-POWER
Year
Year
Two
Three
A
S
A
C
S
S
F
Year
Four
A
S
A
C
S
S
C
S
A
C
S
S
F
F
O
F
O
O
O
O
F
F
O
F
BELWIND
Year
Year
One
Two
F
C
S
C
C
C
S
C
C
C
C
C
R
O
O
R
SELECTED ENVIRONMENTAL IMPACTS
Organic enrichment of surrounding sandy sediments
28000
26000
Mean±0.95*SE
2011
2012
22000
20000
2012
18000
16000
14000
12000
10000
8000
6000
4000
2011
Benthic
density
(ind./m²)
Total
Density (ind./m²)
24000
2000
0
SW 15m
SW 25m
SW 50m
SW 100m
SW 200m
Distance
Distance from scour
protection (m)
SELECTED ENVIRONMENTAL IMPACTS
Fish and the exclusion of fisheries
Density (ind./1000 m²)
Plaice (Pleuronectes platessa)
Outside
wind farm
Inside
wind farm
Length (cm)
ENVIRONMENTAL IMPACTS
Positive or negative? – some hypotheses…
Positive?
Negative?
Higher survival rate
of larger fish
Net increased
production
Increased predation
of smaller fish
(Loss of
natural fauna)
Localized increased
production
Production
Attraction
Seabirds
Food resources
Increased risk
of collision
Marine mammals
(Increased food
availability)
Loss of habitat
Soft-sediment
fish
Soft-sediment
benthos
Fouling
invertebrates
Hard substrate
fish
Production
→ Context setting / research needed…
LESSONS LEARNED
Issues to be considered for future monitoring (part 1)...
1a. Which approaches/guidelines are used for investigation of marine
species and habitats within offshore infrastructure EIA?
•Need for cross-wind farm and international collaboration (e.g. ICES)
1b. What should be improved in the requirements and approaches for
species/habitats?
•Baseline and target monitoring needed: from observation to hypothesis-based
monitoring
2. What are general findings about possible impacts on species and
habitats?
•Few direct and obvious negative impacts mainly during construction phase
•Many (seemingly) “positive” impacts mainly during operational phase
•Discriminating between positive and negative spatial scale- and perspectivedependent
LESSONS LEARNED
Issues to be considered for future monitoring (part 2)...
3a. Which are most problematic issues during biodiversity related EIA
investigations (methods, data gaps, assessment time and replicability)?
3b. What new methods for assessing species and habitats shall be
introduced for EIA?
•Identification of research hypotheses needed, examples:
• From diver-operated sampling to ROV data collection: level of detaildependent
• Radar bird monitoring (dual radar): not all gold that shines (yet)…
•Replicability: major issue for baseline monitoring not that much for targeted
monitoring
Further reading
www.mumm.ac.be
I will be around for further detailing…
www2.mumm.ac.be/winmonbe2013