GDG Offshore Expertise

OFFSHORE EXPERTISE

ABOUT US

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Offering advice, consultancy support and engineering expertise, our team of specialist consultants is focused on developing the most sustainable design solutions for our clients.

With a foundation in geoscience and geotechnical engineering, our expertise has grown to include structural design and cable engineering as well as environmental science and emerging energy technologies.

Since 2011, we have supported offshore wind projects from early site selection, consenting, and planning, through to design, construction, operations and maintenance planning. We work hand-in offshore wind farm developers to take projects from concept through to realisation

Our team of expert engineers and scientists ensures the successful delivery of offshore wind farm projects around the world, many with difficult ground conditions, variable bathymetry, a wide range of geohazards and challenging environmental factors.

We have an international footprint with teams in Ireland, UK, Mainland Europe, APAC and USA.

At GDG, we thrive on engineering innovation, and our team of industry experts constantly push boundaries to define a new state-of-the-art.

info@gdgeo.com

Gavin & Doherty Geosolutions we are experts at finding innovative engineering solutions to support some of the most challenging offshore wind, marine and infrastructure projects around the world.

OFFSHORE CAPABILITIES

We provide specialist design and consultancy services to the offshore sector.

Covering all phases of a project lifecycle, our team has the expertise and experience to support your business in the following areas:

Offshore Design & Consultancy

Transport & Installation Consultancy

Ports & Harbours Design & Consultancy

We also provide expert witness and dispute resolution services.

Offshore Marine Advisory Ground Modelling Survey Management

Our Marine Advisory Team provides services to transform ideas and concepts into tangible projects that can be developed and successfully delivered.

We support offshore projects from conception right through to decommissioning. Particularly valuable during the early stages of projects, we provide bespoke services to meet the specific needs of any project and ensure development activities are front-loaded to deliver successful projects.

MARINE ADVISORY SERVICES

• Strategic advice and development roadmaps

• Programme management and acceleration

• Site identification and constraints analysis

• Feasibility assessments and project definitions

• Government policy and legislative advice

• Licensing and consenting support

• Liaison with regulators and decision makers

• Environmental, planning and technical due diligence

• Ecological survey procurement and management

• Stakeholder engagement and management

• Public consultation events and surveys

Department of Environment, Climate and Communications | Ireland | 2021

Maritime Area Consent (MAC) is a key feature of the Maritime Area Planning (MAP) Act (2021).

At GDG, we developed the technical criteria for the MAC process and undertook the technical assessment of the Phase One application for each relevant project.

Our recommendations were provided to the Minister, allowing him to award a MAC to the relevant projects. A handover and lessons learned workshop and set of documents will be delivered to the Department in 2023.

KEYEXPERIENCE PROJECTS

• Rosslare Europort Offshore Wind Hub

• North Irish Sea Array (NISA)

• Sceirde Rocks

• Dublin Port

• Numerous confidential projects

SURVEY MANAGEMENT

AtGDG, we support the offshore wind industry with bespoke survey

management and site characterisation services.

Our highly-qualified team, with expertise in engineering, geoscience and offshore operations, works in an integrated way to deliver advice and services that are robust, practical and focused on your specific stage of the project lifecycle.

SERVICES

• Survey strategy definition

• Site investigation scoping and development of technical specifications

• Tender management and evaluation

• Provision and management of offshore client representatives

• Laboratory testing strategy development and management

• Quality assurance / health & safety supervision

• Management of vessels and survey contractors

• Landfall and nearshore assessments

• Quality assurance of contractor deliverables

KEYEXPERIENCE

Arklow Bank Wind Park | Ireland | 2018

Arklow Bank Wind Park is an offshore wind farm generating electrical power for the Wicklow region in Ireland.

To support our client, we have provided the following services:

• Site investigation management

• INFOMAR data processing

• Geotechnical risk management

In addition, we are providing offshore client representatives for upcoming survey and site investigation campaigns.

PROJECTS

• North Irish Sea Array

• Codling Wind Park

• Sceirde Rocks Offshore Wind Farm

• Arklow Bank

• Braymore

• Celtic Sea Offshore Wind Farm Baltica I

• North Celtic Sea and Southern Irish Sea

• Kinsale

• Wicklow

• Péarla Offshore Wind Farm

• Realt Na Mara

• Celtic Horizon

• Ocean Winds

GROUND MODELLING

Using ground models can substantially reduce the risks and expenditure associated with offshore developments such as windfarms and other renewable energy projects. At GDG, we are a leading provider of marine geoscience services and we have developed numerous ground models to support the development of offshore projects.

Our expert team develop ground models which incorporate geophysical, hydrographical and geotechnical datasets from various phases of the development to provide you with detailed information on the morphology, geology, geohazards and potential uncertainties throughout the project to support better decision making.

SERVICES

• Offshore site assessment and desktop studies

• Geophysical analysis; processing and interpretation of sub-bottom profile data, including single and multichannel seismic

• Identification of data gaps and site uncertainty

• Geotechnical analysis for classification of soils/rocks and properties complying with national and international testing standards, into geotechnical interpretative reporting (GIR)

• Preliminary and integrated ground models in user-friendly visualisation platforms.

• Development of risk register and Geographical Information Systems databases

• Survey specification and tender evaluation

KEYEXPERIENCE

Codling Wind Park Ltd | Ireland | 2021

We have been supporting the development of Codling Wind Park for several years and during multiple stages of the integrated ground model development.

The mobile and complex stratified geological conditions of the Irish Sea provide a key technical challenge. Our ground modelling team reviewed, analysed and integrated numerous geophysical and geotechnical datasets over the project lifecycle.

Our ground model has since enhanced the knowledge of site geohazards, assisted layout design, and provided a greater understanding of soil conditions for foundation design and geohazard risk management.

PROJECTS

• Arklow Bank

• Baltica 2 & 3

• Baltica 1

• Celtic ORE

• NISA

• Braymore Wind Farm

• Clogherhead Wind Farm

• Oriel Wind Farm

• Dublin Array

• Rampion

• Hai Long

OFFSHORE DESIGN

We provide specialist geotechnical, structural, metocean and cable engineering services to the offshore energy sector. Our detailed knowledge, vast experience of the offshore industry and state-of-theart in-house design tools allows us to deliver innovative, economic and sustainable solutions for our clients.

The wide range of services we offer support all phases of offshore project development enabling you to make better-informed decisions.

SERVICES

• Project management

• Owner’s engineer support

• Substructure screening studies (fixed and floating)

• Design of fixed & floating substructures for offshore wind turbines

• Design of offshore substation platforms

• Metocean assessment, weather downtime and morphodynamic studies

• Subsea cable routing, stability, landfall, installation and protection assessment

• Horizontal Directional Drilling (HDD) design

• Risk assessment and management

• Energy yield assessment and wind farm layout optimisation

• Expert witness and conflict resolution services

KEYEXPERIENCE

Hai Long Offshore Wind Farm | Taiwan | 2019 2022

The 1,044MW Hai Long offshore wind farm is located 50 kilometres off the coast of Changhua county, Taiwan.

At GDG, we delivered detailed engineering for foundation design of offshore substations.

We undertook geotechnical interpretation, seismic assessments including liquefaction, seabed mobility and scour assessments and pile foundation design. Our proprietary software tools enabled efficient design solutions to the project.

PROJECTS

• EA Hub

• Rampion

• Sofia

• Seagreen

• Arklow Bank

• Codling Wind Park

• Courselle and Saint Nazairre

• Dolwin 5 and Borwin 5

• Baltica II and III

• Hai Long

• Phu Cuong

TRANSPORT & INSTALLATION

At GDG, we offer expertise in fixed and floating foundations, cables and wind turbine generator installations. Our Transport & Installation (T&I) team will help you identify the best execution strategies to address key project risks and CAPEX costs.

In the early phase of your project, we will support you by simplifying the decision-making process and reducing costs and time to market. In the later project phases, we offer support and advise in discussions with installation contractors both before and after the T&I contract is in place.

Our expert team also performs dedicated installation analysis, including specialised ground-related studies on areas such as cable burial and pile drivability, as well as weather downtime analysis using unique tools developed in-house.

• T&I concept development

• Installation analysis

• Weather downtime analysis

• Supply chain mapping

• Project execution strategies

• Local content considerations

• Assistance with contract strategy definition

• Budgetary CAPEX cost estimates

• Support with employers’ ITT/RFP requirements

• Risk management support

KEYEXPERIENCE

California Auction | USA| 2022

Our study looked at the feasibility of component fabrication on the US East Coast, Gulf of Mexico, West Coast and in Asian yards.

We considered available and future yard capacities, alternative transportation routes, and small and largesize vessels (Heavy Transport Vessels as well as barges).

We considered the full execution scheme including fabrication, manufacturing, laydown/marshalling, assembly/integration, wet storage, float out, transportation, in‐field staging/integration, and installation and we considered compliance with the Jones Act.

Inis Offshore Wind | Ireland | 2021

The objective of this study was to determine the governing factors from a T&I perspective and establish the constraints in the supply chain with a focus on the foundations and wind turbine generator installation.

The main tasks of the study included:

• Defining preliminary sizing of the jackets

• Defining foundation T&I strategies

• Mapping the installation supply chain

• Engaging with the supply chain to support the developer in preparing the subject RFI and reviewing of contractors’ responses

PORTS AND HARBOURS

Ports and Harbours engineering design is a wide but specialist area within civil engineering, and one that requires an intimate understanding of geotechnical, structural, hydraulic and environmental engineering.

Our highly skilled engineers are at the forefront of marine design. We utilise a vast suite of soil-structure design tools to solve the most complex and challenging engineering issues that often occur within the marine environment.

At GDG, we offer marine civil and structural design, and geotechnical consultancy services in the nearshore environment. Our in-house expertise in marine advisory and planning services enables a holistic project approach. In addition, for offshore-specific commissions, we offer extensive offshore expertise, including Transport & Installation.

SERVICES

• Port master-planning

• Concept / preliminary design

• Feasibility studies

• Survey management

• Site investigation

• Detailed design

• Cost estimation

• Risk assessment

• Temporary works design

• Tendering and procurement

• Contract administration

• Site supervision

KEYEXPERIENCE

Dublin Port | Ireland | 2016 -

At GDG, we were commissioned to provide detailed designs for a number of strategically important port infrastructure schemes in Dublin Port, including:

• Design of a 170m long combi wall and two bankseat structures at Crossberth Quay

• Design of a 250m long jetty structure with 9 dolphins with berthing on either side at RoRo Jetty

• IED Environmental Dredging & Bund including followon dismantling and relocation of the bund

• Early Contractor Involvement (ECI) for the design of a new jetty and wave wall structures to accommodate 240m long ferries, with 8 dolphins

PROJECTS

• Greenock Ocean Terminal

• Ros An Mhíl Deep Water Quay

• Rosslare Offshore Wind Hub

• Bremore Ireland Port

• Shannon LNG Terminal

• Castletownbere Piled Slipway

• Athlone Piled Slipway

• Fecamp Cable Installation

• Dun Laoghaire Baths

• Donegal Pier Inspections

• Various O&M Base Studies

• Wide Range of Temp Works