66a89aa1-f717-4cd1-9924-e88ea015c38e eng G2467_SSS series ABP Marine Environmental Research Ltd 02380711840 Quayside Suite, Medina Chambers, Town Quay Southampton SO14 2AQ United Kingdom enquiries@abpmer.co.uk http://www.abpmer.co.uk pointOfContact 2019-06-17 MEDIN Discovery Profile 2.3 urn:ogc:def:crs:EPSG::32631 2018, Fugro, Sheringham Shoal Offshore Wind Farm, Seabed Monitoring Survey 2014-03-05 publication 2012-10-08 G2467_SSS Fugro was commissioned by Equinor (U.K) Ltd, hereafter referred to as the Client, to conduct a bathymetry and sidescan sonar (SSS) survey of the Sheringham Shoal Offshore Wind Farm and export cables. The survey was conducted as part of ongoing preventative maintenance. The survey objectives included the following: ■ Acquisition of multibeam echosounder (MBES) data around the 88 WTG and the two OSS locations for the monitoring of scour; ■ Acquisition of MBES and SSS data along the export cable and inter array cables for the detection of exposures and potential cable freespan; ■ Acquisition of SSS data over the main site and export cable for the detection of contacts. The survey was undertaken between 17 October 2018 to 23 November 2018 on board MV Mintis. The presence of fishing gear in the nearshore zone of the export cable route meant full sidescan sonar and bathymetry coverage could not be attained. Data acquisition in these areas was a safety issue and it was agreed following consultation with the Client that the gaps were acceptable given the circumstances. The Crown Estate +44 020 7851 5000 16 New Burlington Place London W1S 2HX United Kingdom enquiries@thecrownestate.co.uk http://www.thecrownestate.co.uk custodian Fugro +44 (0)2392 205500 Victory House,Trafalgar Wharf (Unit 16) Portsmouth Hampshire PO6 4PX United Kingdom unknown www.fugro.com originator asNeeded Side-scan sonar SeaDataNet Parameter Discovery Vocabulary 2018-09-07 revision 109 Bathymetry and Elevation SeaDataNet Parameter Discovery Vocabulary 2018-09-07 revision 109 Offshore Cable Corridor The Crown Estate Renewable Energy Development Areas 2012-05-15 revision 1 Renewable Energy Lease area The Crown Estate Renewable Energy Development Areas 2012-05-15 revision 1 Post-Construction monitoring The Crown Estate Renewable Energy Development Phases 2012-05-15 revision 1 Offshore Substation The Crown Estate Renewable Energy Development Areas 2012-05-15 revision 1 Marine Environmental Data and Information Network Marine Environmental Data and Information Network No restrictions intellectualPropertyRights intellectualPropertyRights No restrictions 1 eng elevation geoscientificInformation 0.828491 1.231625 52.948708 53.182847 2018-10-17 2018-11-23 series The Starfix primary positioning system worked well throughout the survey with no prolonged drop-outs. Vessel positioning was of high quality and within the limits specified in the contract. Further postprocessing within Fugro Starfix VBA Proc software ensured that all position data were within specification and accurately reduced to LAT. The bathymetry data collected were of good quality. Any obvious noise present in the data was removed and the remaining data were corrected for variations in positioning quality. Following processing, bathymetric sounding standard deviation values were also assessed to ensure that data were consistent, vertically aligned and no erroneous soundings were present. Bathymetric differences were assessed between the autumn 2018 survey and the winter 2015 and 2014 surveys. The checks were conducted on regions of flat seabed where no visible effects from construction or sand dune migration were evident. In these regions vertical differences were typically less than less than 0.15 m. This check provided further confidence that the datasets were correctly positioned and of high accuracy. The SSS data was of good quality and fit for purpose. Detection of small objects such as fishing gear pots (less than 0.5 m in length), the ropes connecting them (less than 0.1 m in diameter) and cable exposures, were successful achieved across the main site and on the export cable route. The presence of fishing gear and depth limitations in the nearshore area of the cable route area meant full sidescan sonar and bathymetry coverage could not be attained. Data acquisition in these areas was a safety issue and it was agreed following consultation with the Client that the gaps were acceptable given the circumstances https://www.marinedataexchange.co.uk/details/1975/summary A link to the web service or dataset. https://www.marinedataexchange.co.uk A link to the general host site.