Artificial reef creation using decommissioned mattresses – environmental performance and fisheries enhancement potential in the North Sea
Many offshore oil and gas fields are reaching the end of their production life and will soon require decommissioning. From 2017 to 2025 decommissioning is forecast to take place on 349 fields across all regions of the North Sea, including six fields on the Danish Continental Shelf, 23 fields on the Norwegian Continental Shelf, 106 on the Dutch Continental shelf and 214 fields on the United Kingdom Continental Shelf. Within these fields around 200 platforms and 7,800km of pipeline are due to be decommissioned. It is estimated that these operations will cost a staggering £17 billion between 2017 and 2025 on the UKCS alone.
The majority of the 7,800km of pipeline exhibit some form of pipeline protection, the most commonly used being concrete mattresses (flexible rectangular concrete structures laid over the top of pipelines, see image) of which an estimated 40,000 remain in the North Sea, all of which need to be accounted for in the decommissioning process. At present, the mattresses are being removed and transported onshore, where they are recycled and re-used in other capacities such as laying foundations for roads, as coastal protections or as an aggregate.
My work investigates the potential use of these mattresses within the marine environment as artificial reefs be it in situ or at other suitable sites such as around the bases of offshore wind turbines. My research includes, but is not limited to, quantifying benthic interactions and fish assemblages associated with pipeline protections, investigating scale-dependent habitat complexity of protections, and quantifying inorganic (heavy metal) contaminants in concrete mattresses.
With this work, we gain new insights into re-purposing pipeline protection and further inform the decommissioning process.
Dr Tom Wilding, SAMS
Dr Sally Rouse, SAMS
Dr Peter Hayes, Marine Scotland Science
European Social Fund
2015 Marine Biologist. Cruise Whitsundays - Great Barrier Reef
2012-16 Marine Mammal Observer / Passive acoustic monitoring operator. RPS Energy
2017 MSc with Distinction in Biodiversity Conservation. Bournemouth University
2010 BSc (Hons) Environmental Science. University of Plymouth