Distance dependent study on noise emIsSSIoNs 
due to pile driving in recent offshore construc- / 
tion projects in the German North Sea LAN 
N A MariInEARS © 
en Schmidt, Carina Juretzek Marine Explorer & Registry 5000 nr 
BUNDESAMT FÜR 
SEESCHIFFFAHRT 
UND 
=HYDROGRAPHIE 
Scope of this study 
ville driving Is one of the most intensive anthropogenic noise sources In the marine environment. Each foundation pile may require up to a few thousand strokes with 
ıgh hammer energy to drive to the embedded depth. Scientific evidence shows that impacts on the marine environment have to be anticipated if no mitigatior 
neasures are applied. Pıle driving events analysed here, occurred during a recent foundation construction phase In a wind farm cluster wıth monopile Installation 
jositions located In water depths between approximately 38 and 40 m. Here, we evaluated the acoustic measurements in a standardised monitoring distance of 
7/50 and 1500 m to each of the pile driving locations !!?l and at a temporary fixed monitoring station (data resource: MarinEARS !$ 4), 
Piling noise at 750 m distance 
igure: SEL95 (blue) and Lpeak (black) values evaluated from acoustic monitoring data recorded in a dis- 
ınce of 750 m to the pile driving location in comparison to the dual threshold criteria 
-or all, but one pile driving event (pile 17) technical noise abatement systems were applied. Results 
or pille 17 correspond to a test measurement, which allows evaluating the unmitigated noise emissions 
with respect to the project site and construction conditions. Resulting SEL95 in 750 m distance to the 
30urce do not exceed a value of 160 dB re 1 uPa$*s for all but 5 piling events, and none of the mitigated 
olle driving activities ylelds a SELos above 161 dB. Observed Lpeak values remain well below the 
threshold of 190 dB re 1 uPa. 
{ | 1 
SEL (by .50m : hi iR} 1 
Lpeak - 750m ; 8 1 
FT ; 1 
12 3 45 11” 13141516 17 18 19 20 21 22 23 
Piling noise at different distances 
Igure: (a) SEL95 and Lpeak values evaluated from acoustic mon- 
oring data recorded at the temporary fixed monitoring station. 
b) Corresponding distances between the fixed monitoring sta- 
ion and the Individual pile driving locations. 
Jbserved SEL95 and Lpeak values show an overall decrease 
with distance to the pile driving location. Pile 17 corresponds to 
a test measurement with only one nolse abatement system and 
therefore ylelds higher values. 
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Effect of noise abatement systems 
-igure: Narrow-band analysis showing hammer strokes for different noise abatement system configurations but comparable hammer energies, evaluated at 
500 m distance to the pile driving location. (a) Pıle 17 without noise abatement systems: (b) piıle 17 wıth IHGC-NMS; and (c) pile 23 wıth IHC-NMS and DBBC. 
3oth the Double Big Bubble (a) 
„urtain (DBBC) and the IHC- 
Noise Mitigation Screen 
IHC-NMS) significantly re- 
juce the sound level over 
16 entire frequency range. 
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Energy content of hammer strokes 
rigure: Histogram of the proportion of acoustic energy within the low-fregquency range 
:< 250 Hz) for all hammer strokes evaluated at 1500 m distance for selected pile driving events. 
Ale driving In itself Is a low frequency sound source with more than 85 % of the energy below 
250 Hz (see pile 17). The DBBC and IHC-NMS are particularly effective at mitigating high-fre- 
Juency sound so that, using these noise mitigation systems, more than 95 % of the energy Is 
below 250 Hz (see other piles) 
1.5km Pile 17, no BBC 
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80 85 90 95 100 80 85 90 95 100 
Energy below 250Hz [%] Energy below 250Hz [%] 
1.5km Pike 18 1.5km Pile 21 
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Energy below 250Hz [%] 
1.5km Pile 23 
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Energy below 250Hz ([%] 
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1] BSH, 2011. Offshore-Windparks Messvorschrift für Unterwasserschallmessungen 
2] BSH, 2013. Offshore-Windparks Messvorschrift für die quantitative Bestimmung der Wirksamkeit von Schalldimmmaßnahmen 
3] MarinEARS, https://marinears.bsh.de 
4] Underwater noise at BSH, https://www.bsh.de/DE/THEMEN/Offshore/Umweltpruefung/Unterwasserschall MarinEARS/unterwasserschall-marinears_node.htm 
5] BMU, 2013. Schallschutzkonzent 
ontact: marinears@bsh.de 
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