Minutes of the 8th NSHC Resurvey Working Group at St. Mandé, Paris, 18-19th September 2018

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Minutes of the 8th North Sea Hydrographic Commission Resurvey Working Group (RWG)
SHOM Office, Pôle Géosciences, St Mandé, Paris, 18-19th September 2018


• BE: Johan Verstraeten
• DE: Bernd Vahernkamp
• DK: Lars Hansen
• FR: Vincent Lammare (SHOM), Thierry Garlan (SHOM), Sandrine le Jeune (SHOM), Thierry Schmitt (SHOM)
• NL: Sjoerd Knoop
• UK: Phil Payne (Chair), Hannah Doddrell (Secretary), David Parker (UKHO), Robert Kinnear (Observer)
Apologies – SE: Ulf Olsson

Welcome and Opening Formalities

• Welcome from Chair and introductions
o On-going Action: Open invite to be sent to all countries on the NSHC (of interest were Norway, Iceland and Ireland)
• No issues raised with minutes from 7th RWG
• Agenda for 8th RWG reviewed and Chair invited for items to be added throughout
• Review of actions from 7th RWG
• Review of TOR

Status of Actions from 7th RWG – Annex B

• Raised that we should number the RWG with actions in the tables – Action for Secretary
• Action 19-6th RWG – has the paper been distributed?
o Carry Over Action – UK to provide CUBE Paper to RWG
• Action 1-7th RWG – France have supplied Technical Hydrographic Instructions
o New Action – all nations to supply where available
• Action 2-7th RWG – Action for Chair – share password with all MS in RWG
• Action 3-7th RWG – raised that there was no need to duplicate links that were already available on the IHO website and it was therefore agreed a link will be inserted onto the NSHC RWG website to the IHO website
o Action – all MS to check links to INSPIRE portals on IHO Website
o Action – DE to insert link to IHO website on NSHC RWG website
• Action 4-7th RWG – overtaken by events
• Actions 7-10 from 7th RWG to be discussed within 8th RWG agenda items
• Action 11-7th RWG – overtaken by events
• Action 12-7th RWG – carried over as agenda item into 8th RWG
• Action 13-7th RWG – Action for UK – forward MCA contact details to DE for upload onto website

Review of Terms of Reference (TOR)

• Discussion on main purpose of RWG undertaken. Should we be interested in areas outside of ‘re-survey’
o Decision – we will use Action 10 to determine re-survey areas to focus our work but we won’t be ignoring the other areas in our waters
• DK – discussion on work with the Baltic Sea Hydrographic Commission (BSHC) and review of their portal. They are mainly focused on getting data to IHO Order 1A
• Discussion on how we define re-survey
o Decision – agreed that 25-years is the cut-off for re-survey
o Action – all MS to provide CATZOCs within the S23 area defined at the 7th RWG to DE for upload to the restricted area of the website by the end of October
o Action – all MS to provide SHP for re-survey areas up with an ‘interval’ Attribute
o Action – DE to upload SHP files and classify intervals into:

0-1 years/as required
1-6 years
6-12 years
12-25 years
>25 years

• A number of comments and actions were raised for edits to be made to the TOR:

o Action – Alternate Surveying methods to be added into TOR
o Action – amend spelling of Dover Strait in second paragraph
o Action – update geographical area to match S23 area agreed at 7th RWG
o Action – add in a comment to state that the RWG pays particular attention to re-survey areas and areas of mutual interest
o Action – mention that re-survey areas exclude Ports
o Action – remove the following line: ‘Additionally, the NSHC Resurvey Working Group is tasked for the Dover Strait/Pas de Calais’
o Action – amend 1.13 to: To share up-to-date Technical Hydrographic Instructions between Member States and to make them available on the NSHC website
o Action – remove 2.7, 2.8 and 2.9 from the Rules of Procedure

North Sea/DSSS Risk Assessment

• The RWG have been tasked by the NSHC to develop a harmonised risk map. There is no North Sea wide risk assessment but the RWG will consider this for the DSSS area due to its specific characteristics
• Each MS gave their current state with regards to risk assessments:

o FR – have conducted an analysis of dynamic areas which require re-survey but currently do not conduct a risk analysis. They plan to develop a risk analysis tool with a university in Brest but for full assessment with cost-benefit analysis would be the next step
o UK – have a UK wide GIS prioritisation tool, which includes geospatial layers (traffic density, age/quality of data, seabed mobility, TSS, IMO routing measures, incidents, under-keel clearance)
o NL – ‘assume’ risk analysis is fed into survey intervals
o BE – no real risk analysis available but have elements that are closely related e.g. access policy for deep draught ships but doesn’t impact survey

• DK showed the risk analysis developed by the Arctic Regional Hydrographic Commission based on CATZOC, traffic, depth
• Chair – the resurvey plan is almost the output of the risk assessment
• Discussion between MS on AIS data – how could we access it and be sure of the accuracy? (could we obtain a GeoTIFF from Norway?)


• Each MS to get CATZOC and interval SHP files together from Actions 9 and 10 along with small discussion piece of what has been considered when producing their resurvey scheme. This will be taken back to the NSHC in a report, which will state that work is on-going and continually evolving in each MS. This will be reviewed at the 9th RWG.

DE – Status of Bathymetric Data Model & Other Website Developments
• New features demonstrated and included seabed models to retrieve depth information for specific point with metadata, source references (overview of where data has come from), GEBCO data, rainbow depth colour map and depth profiler
• Reviewed use of EMODnet
• No issues raised

FR – News on EMODnet High Resolution Seabed Mapping
• Overview given of EMODnet, products, services, DTM construction, DTM 2016 v 2018 comparison, quality assessment, refining coastal areas, SDB in Channel Islands (EOMAP)
• NL-FR to cross check data supplied due to error in NL MBES frequency

Updates on National Development Plans

• 2017 – Flemish minister for Public Works announces full MBES coverage for Belgian part of North Sea
• 2018 – Marine Spatial Plan for 2020-2026 (currently open for comments)
• 2016 re-survey priorities are used to define areas for dredging and dumping, coastal defence, IMO navigation areas, shipping traffic density, risks of grounding and windfarm areas.
• BE now able to plan surveys for the next 50-years but the tool doesn’t allow for considerations on large areas with low priority having a larger survey effort requirement.
• Wind farms are surveyed as part of licence requirements but data isn’t provided for cartographic purposes

• A common resurvey plan is in place down to 20m and is developed for every 6-years
• MBES where possible, SBES in shallow areas and Lidar (0.5-1m) and currently aiming for 10cm accuracy

• The proposal to the IMO for a new TSS in Skagerrak and Kattegat has been approved since the 7th RWG and it is intended to come into operation on 1st June 2020
• TSS introduced in Skagen West and Skagen East (AIS data shows importance)
• Recommend routes from 7th RWG between Skagerrak and Skagen approved
• Prior to implementation routes will be surveyed to S44 standard
• 2 x DWR introduced
• All changes result in new ENCs (Swedish & Danish),

• 4-year national hydrographic programme in place, which is updated every 1-2 years
• Recent surveys include Ouessant TSS, Pas de Calais, Dunkerque offshore wind farm
• Planned surveys include Ouessant/North Brittany TSS, Chausey Island, North of Mont-Saint-Michel Bay Dover Strait Strategy – focused approach in place (Dunes II Project report) – limits survey to most critical dunes, aiming for definitive version in 2023
• Update on FR survey strategy since 2013

 o SHOM use a GIS tool for dune monitoring, 15 dunes have been chosen for monitoring the TSS
o Mega-Ripples have been detected with MBES that are more complex to compare
o Between 2013-2015 there has been a generalised movement of dunes towards the north, those that didn’t are protected by the Sandettie Bank
o 5 dunes have been added in the North East and 1 in the Westo Dunes 2, 5 and 6 are in UK Waters – noted that Hydrographic Notes should come to the UK first and data should be shared

Action for UK – FCO to approve surveying in the UK waters for this study and FR and UK to look into agreements for surveying in each other’s waters by end of year to allow SHOM to plan Surveys

Action for FR – supply polygons of survey area and description of study to UK

• 2017 work has included replacing data-services on ships and switching to GNSS Marine Star
• Current projects are mid-life up-keep of ships, transfer to EM2040D MBES, replacement of magnetometer, development of an ESB (3-day self-supporting vessel), replacement of their Side Scan Sonar and an ADCP has been purchased
• SDB is mainly completed by the military
• Moving away from wire-sweeping and introducing water column data
• In 2018 MBES surveys have been focused in the North
• Next Year there are hopes to work in the Caribbean

• Overview of 2018-2019 surveys plans (Capital and Resurvey)
• Overview of CATZOC
• Highlighted mobile areas are focused in SE
• Announcement of new civil contracts (Shallow – Clinton, Medium – MeriTaito, RRS – A2Sea Ltd),
• 10 capital surveys for 2018-2019
• Overview of planned RRS for this year

Crowdsourced Bathymetry (including review and comments on IHO CSB Paper)

• Commission has asked for a paper on how it impacts the RWG
o Action – UK to produce short paper to pass around group and present to NSHC
• UK – uncertainty of CSB is a greater issue in regularly surveyed areas
• DK – issues with non-use of data regarding liability/legal aspects.
• FR – this is general, doesn’t need to specific to the North Sea area, most of our areas are surveyed to a high standard but a very specific area with lots of traffic and limited under-keel clearance. Trust CSB in areas in areas with less traffic? Can we use a vessel/organisation that crosses all our waters?

Links to UK point regarding options for using ferries/commercial vessels
FR think it can be used to develop cooperation but in the first instance it will probably be more of a scientific approach

• FR – Trusted nodes are highly conceptual currently
• Discussions around use of CSB in shallow, dynamic areas and use of GEBCO and CSB data on Charts
o UK – fill in deep Areas
o DK – NOAA said that they use CSB/ships of opportunity to target surveys & if they have to they will use the CSB – only what you have

• Decision – the RWG are happy with the paper itself but there are legal issues regarding non-use of data. All activity remains at national level and there is potential for change analysis. However, more information is needed to obtain trusted sources

• Action – all MS to look into options and share via email as it comes up and discuss at 9th RWG
SHOM work with CSB

• Olex coverage in Bay of Biscay/English Channel areas in France. Issues merging data into one large XYZ but there is good coverage even if only SBES
o Comparisons have been made with MBES data but no information on how data has been corrected (especially tidal)
• SHOM have contributed to the IHO CSB paper – especially on data collection & metadata
o Trusted nodes do first filtering of the data
• UK Question – no information on applying tides in paper?
o FR answer – the idea is that the potential user will apply tide when required, stored at trusted node without tide. Data should be time-stamped to help track down past tidal data.

Application of Alternative Survey Methods

Satellite Derived Bathymetry (SDB)
• SHOM Perspective

o Current focuses at SHOM with regards to remote sensing are updating coastal topography & shallow water bathymetry)
o CATZOC doesn’t seem appropriate for SDB
o They are starting a new research and development phase looking at physics-based models
o FR don’t put soundings on chart when satellites have been used – they use banded colour depths

UK do put soundings on but with advice

• FR Action – supply specifications they use to the NSHC site
• Action – those interested to consider SDB and to share any findings or experiments conducted to date with the RWG

• FR – Shallow Water Bathymetry from Spectral Wave Analysis

o SHOM are working with the University of Toulouse and IRD with the objective to obtain bathymetry in areas without hydrographic surveys (e.g. West Africa)
o The Pleiades system is in use and the first results are good. This has been used on a drone at 300m
o A new study beginning next week to move onto SDB – results will be available in a year
o Depths range from 5-20/30m


French National Programme – Litto3D
o Conducted due to a lack of data on sea-land interface in France and with the purpose to produce a high-resolution elevation model
o IGN (French Topographic Service) & SHOM cooperation
o Equipment in use – HawkEye III, Cessna Grand Caravan + Pilots, topographic and shallow water lasers, 2 cameras, 17 people processing
o First survey was in 2016 from Mont St Michel Bay to the Belgian border. Depths obtained down to 22m, 10m in the sallow and in the Dunkerque area there was no penetration of the water showing the challenges of using Lidar in the North Sea

1 flight requires 6-days of manual cleaning.
Data is free to download at data.shom.fr & diffusion.shom.fr

• BE co-operation with SHOM/Litto3D

    o Started to develop a tool to estimate survey time in 2016. Found that efficiency for MBES in shallow water is 4 hours per sq.km
o Obtained 2016 SHOM Litto3D data near French Border
o 2017 – made an agreement with SHOM for extended demonstration

• UK experience in the Caribbean
o Part of the Overseas Territories and Commonwealth Marine Economies Programme
o Overview of St Vincent and the Grenadines and Grenada (5,800 sq.km) – used 2 SHOALS & 1 REIGL System
o Overview of work in Belize with MBES and Lidar with RAMMS system and comparison of object detection (12m, 8m, 6m objects, reduced/lack of for 2m objects) and data density
o Planned this year – Turks & Caicos, Belize, British Virgin Islands

• UK Action – to provide Lidar specification once completed for website
• FR Action – to provide Lidar specification for website

Autonomous Surveying
• No major studies conducted to date
• Action – MS to report any studies
• Vessel safety seen as a greater issue than survey data
• Decision – to remain on agenda for 9th RWG

AOB – MARID Conferences
• Bremen 2019: 1-3 April 2019
• Safety of navigation, mine burial, marine aggregates, marine renewable energy, protection of pipelines and cables, MPAs, wave/tide/noise modelling, research of containers
• 2-days + visit
• 35-40 presentations, 15-20 posters
• Abstract submission by 30th October 2018
• Topics – geomorphological evolution, sedimentary properties, hydro and morphodynamical modelling, bio-geomorphology, environmental management.

Closing Formalities and Future RWG Meetings

• Chair thanked all for involvement
• Future of RWG – all MS content this was covered in the review of TOR
• Propose to keep meeting annual
• UK content to chair for foreseeable future
• Most urgent actions from this meeting – supply of CATZOCs and resurvey plans
• BE raised that they have a tender out for advanced processing techniques and it was noted that this should be an agenda item for next year for the RWG to receive an update on the progress
• All MS willing to share presentations from this RWG – pass to DE for upload onto website
• Action – Denmark to host in 2019
• Action – Netherlands to host in 2020

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