Environmental impact monitoring of offshore wind farms in Belgian waters Royal Belgian Institute of Natural Sciences Management Unit of the North Sea Mathematical Models Steven Degraer and collaborators 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 • Thorntonbank • 56 turbines of 5 and 6 MW (total of 300 MW) • Phase I: six turbines (gravity base foundations) operational since May 2009 • Phase II: 48 turbines (jacket foundations) partly operational since 2012 Belwind • Bligh Bank • 110 turbines of 3 MW (330 MW) • 55 WT + 1 OHVS built on monopiles • in 2009-2010 • Operational since December 2010 Belwind Northwind Northwind • Lodewijkbank • 72 turbines of 3 MW (216 MW) • Environmental permit “granted” C-Power • Construction starts in 2013 Other consortia • In pipeline... 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 Targeted monitoring • Focus on cause-effect relationships • Focus on a posteriori resultant effect of selected, a priori defined impacts quantification • From observation-driven to • Site-specific hypothesis-driven monitoring • Observing rather than understanding • Understanding rather than observing impacts impacts • Basis for halting activities • Basis for mitigating activities and future policy Phocoena phocoena Balanus perforatus Gadus morhua
SELECTED ENVIRONMENTAL IMPACTS Pile driving disturbance of marine mammals Aerial survey results Phocoena phocoena
SELECTED ENVIRONMENTAL IMPACTS Pile driving disturbance of marine mammals Passive acoustic monitoring detection positive minutes / hour Pile driving events Time (Date)
SELECTED ENVIRONMENTAL IMPACTS Attraction and macro-avoidance of seabirds Little gull Common gull Lesser black-backed gull Predicted density (ind./km ² ) Herring gull Black-legged kittiwake Greater black-backed gull Month No impact Reference area Impact area
SELECTED ENVIRONMENTAL IMPACTS Attraction of fish Small-scale distribution of cod ( Gadus morhua ) Number of detections Jassa herdmani Distance from foundation (m) • Attraction of fish up to 29.000 individuals of pouting per windmill ! – • Attraction-production hypothesis – Hard substrate epifauna is an important food source for pouting ( Trisopterus luscus )
SELECTED ENVIRONMENTAL IMPACTS Artificial hard substrate and epifouling invertebrates 30 Species richness (n/0.06 m ² ) 25 Gravity based foundation Species richness (S) 20 15 10 Monopile foundation 5 Surface area 0 Summer1 Fall1 Winter1 Spring2 Summer2 Fall2 Winter2 Spring3 Summer3 Fall3 Winter3 Spring4 GBF: ± 3000 m ² monopile: ± 500 m ² Time after installation Epifauna on new hard substrates (i.e. foundations) in a sandy environment – ecological succession to a rich and diverse community ( 101 species ) – dominant organisms are barnacles, mollusks and crustaceans
SELECTED ENVIRONMENTAL IMPACTS Artificial hard substrate and non-indigenous species C-POWER BELWIND Year Year Year Year Year Year One Two Three Four One Two Megabalanus coccopoma (Darwin, 1854) C F Balanus perforatus Bruguiére, 1789 S A A C C Telmatogeton japonicus Tokunaga, 1933 S S S S S Elminius modestus Darwin, 1854 A A A A C C Jassa marmorata (Holmes, 1903) C C C C C S Mytilus edulis (Linneaus, 1758) F S S S C C Semibalanus balanoides (Linnaeus, 1758) S S S C C Balanus crenatus Bruguiére, 1789 F C R Patella vulgata Linnaeus, 1758 F F Hemigrapsus sanguineus (De Haan, 1835) F F Crassostrea gigas (Thunberg, 1793) O O Littorina littorea (Linnaeus, 1758) F F Balanus improvisus Darwin, 1854 O O R Emplectonema gracile (Johnston, 1873) O Emplectonema neesii (Örsted, 1843) O Pleioplana atomata (OF Müller, 1776) O Eulalia viridis (Johnston, 1829) O
SELECTED ENVIRONMENTAL IMPACTS Organic enrichment of surrounding sandy sediments SW Mean±0.95*SE SE 12000 NW NE Benthic density (ind./m ² ) Mean Total Density (ind./m ² ) 10000 8000 6000 4000 2000 0 15m 25m 50m 100m 200m Distance from scour protection (m) Distance from scour protection (m)
SELECTED ENVIRONMENTAL IMPACTS Fish and the exclusion of fisheries Plaice ( Pleuronectes platessa ) Density (ind./1000 m ² ) Outside wind farm Inside wind farm Length (cm)
ENVIRONMENTAL IMPACTS Positive or negative? – some hypotheses … Negative? Positive? Increased predation Higher survival rate Soft-sediment of smaller fish of larger fish fish (Loss of Soft-sediment Production natural fauna) benthos Fouling Localized increased Net increased invertebrates production production Hard substrate Production Attraction fish Increased risk Seabirds Food resources of collision (Increased food Marine mammals Direct mortality availability) → Context setting / research needed …
ENVIRONMENTAL IMPACTS Offshore wind farms and other renewable energy installations X X X Soft-sediment fish Increased length of fish X X X Soft-sediment benthos Elevated densities New habitat for hard Fouling invertebrates X X X substrate species X X Intertidal invasives X X X Hard substrate fish Attraction & production X X (X) Seabirds Attraction X Collision Marine mammals Construction noise X (X) disturbance
Further reading www.mumm.ac.be I will be around for further detailing …
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