The monitoring of Nord Stream 2 offshore construction activities in 2019 shows that there were no impacts other than those that had been predicted. In the Russian onshore section, there were no significant impacts on the biotic and abiotic environment of the protected area.
In 2019, the monitoring focused on relevant physical-chemical (e.g. water quality and air quality), biotic (e.g. birds and marine mammals) and socio-economic (e.g. cultural heritage and ship traffic) environments. The objective was to observe potential impacts caused by the construction activities implemented offshore (in Russia, Finland, Sweden, Germany) and onshore (in Russia, Germany). Construction activities included pipelay, rock placement, cofferdam installation, post-lay trenching and dredging/backfilling.
Also additional monitoring activities were carried out through specialist studies to enhance scientific knowledge of for example the Baltic Sea environment.
Extensive mitigation measures have been implemented throughout the construction phase. Conformance to the environmental and social management system has been monitored through an environmental and social auditing programme.
The monitoring results offshore verified that:
- In German waters, the impact of construction activities performed in 2018 – i.e. dredging, pipelay and backfilling – on the seabed was in line with the assessment as demonstrated by post-construction monitoring of 2019. Exclusive use of backhoe dredgers during dredging inside protected Natura 2000 habitats proved to be a successful mitigation measure, allowing minimisation of the spatial footprint. No contamination of the seabed sediments was observed.
- In Swedish waters, underwater noise associated with pipelay and rock placement was comparable to or lower in level and frequency than noise from commercial cargo ships in the area. This supported the initial assessment that no harm occurred to the marine mammals.
- Additional monitoring provided valuable information for the scientific community: for example, a previously unknown pod of grey seals was found at the Sommers island rockery, and the round trip of a tracked Baltic ringed seal to western Estonia was identified for the first time.
- Monitoring of third-party shipping traffic demonstrated that risk mitigation measures were successfully implemented during construction in all countries. No incidents were recorded.
- Project activities in Finnish, Swedish and Danish waters did not disturb cultural heritage objects.
- There were no chance finds of munitions and cultural heritage objects in Danish waters.
- The spawning of Baltic herring and the seasonal salmon migrations were not impacted.
- No significant impacts on water quality occurred during pipelay, dredging, trenching and rock placement. The results were in compliance with the requirements set by national standards.
- In the Russian nearshore section, installation of the cofferdam successfully prevented increase of turbidity and general impacts on water quality during the main construction activities in shallow waters. Analysis of seabed sediments demonstrated no significant increase in pollutant concentrations in the areas where seabed intervention work took place. The monitoring of soil quality, exogenous processes and hydrology mostly displayed values within the natural variability of the area.
Monitoring results onshore verified that:
- In Russia, there were no significant impacts on the flora and fauna of the Kurgalsky Nature Reserve (also at the boundaries of the Kader swamp), which confirmed the conclusions of the environmental impact assessment.
- Red Data Book Species relocated in 2018 in Kurgalsky Nature Reserve, e.g. Aulacomnium androgynum and Epipactis atrorubens, were in a good condition. The hydrological regime of the area was not impacted by the construction activities and no hazardous exogenous processes were detected throughout 2019.
- In Germany, airborne noise monitoring at monitoring sites did not detect an acoustic impact from construction noise.
Nord Stream 2 environmental monitoring is based on the national environmental monitoring programmes for Russia, Finland, Sweden, Denmark and Germany, approved by the competent national authorities. The monitoring work is designed to verify that project implementation does not have a significant impact on the Baltic Sea environment and to fulfil the requirements and commitments under the respective jurisdictions of the five countries in which the Nord Stream 2 pipeline is built.
Up to 40 independent contractors have been monitoring the actual impacts on the environment and marine life. The collected data is submitted to environmental consultants, who draft the monitoring reports for regular submission to the national authorities.
By the end of 2020, Nord Stream 2 will have invested over 100 million euros in environmental surveys, assessments, analyses, monitoring and conservation activities.
See the Overall Environmental Monitoring Report 2019 here.
Read more about Nord Stream 2’s environmental monitoring in the infographic here.
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Read the article online at: https://www.worldpipelines.com/project-news/29032021/nord-stream-2-annual-environmental-monitoring-report-2019-published/