What is a Navigation Risk Assessment?

A navigation risk assessment (NRA) is a proactive measure to identify and assess the potential hazards and risks with initially assumed mandatory mitigating actions in place, to the navigation of ocean going vessels around ports and harbours, aquaculture sites, and designated deployment sites for offshore marine renewable energy, before considering mitigating actions to minimise the risks to a level of at least ‘As Low As Reasonably Practical’ (ALARP). 

A traditional approach to NRAs is to use a structure process of risk identification, assessment and management that takes into account the local conditions and relevant data sources, and the Hazard Identification and Risk Assessment (HIRA) process. 

The main sources of data and information are marine environment and MetOcean data, marine traffic density analysis from AIS data logs, high level project method statements, and operational experience from seafarers working in the locality. 

Using the above sources of data, hazards will be identified through a series of workshops with project personnel and professional mariners. A set of guidewords are produced and used to identify potential hazards and are adapted to the specific project. 


 ‘Structured what if technique’ (SWIfT) technique

The workshops utilises a ‘structured what if technique’ (SWIfT) technique to review the high level project method statements. The risk assessment is carried out using definitions for frequency and consequence and a tolerability matrix that are based on ISO 17776  ‘Guidelines on Tools and Techniques for Hazard Identification and Risk Assessment’. A mainly qualitative approach is taken to assess the frequency of an event for a defined consequence, using such data as the Marine Accident Annual Reports as a guide for accident statistics. 


Our Knowledge

We utilise our vast knowledge and deep understanding of the risks involved in navigation from decades of marine operation and sea-going experience within the core team and our team of consultants. 

The NRAs are accomplished with guidance from classification societies, best practices, and national marine governing organisations. The core team and our consultants are highly familiar with the guidance set out for navigational practices, safety, operations, and marine risk assessments. This allows us to safely and efficiently assess the hazards and provide mitigating actions to minimise the risk to an acceptable risk level. 


Our Experience

Orcades Marine has successfully performed project specific navigation risk assessments for a number of marine renewable developers and for local and international harbour authorities. 

The NRAs applied to the installations of marine renewable devices at proposed deployment sites and it assessed the potential risks to other sea-going vessels when the device is installed at the specified deployment site. We have performed the navigation risk assessments for a number of marine renewable developers who were proposing to install their tidal energy converter devices in locations spanning from the Faroe Islands to Scotland to Singapore. 


Our Projects

West coast of Orkney

An NRA was completed for a wave energy developer client who deployed their device on a wave energy site off the West coast of Orkney. This NRA covered the installation, operation, planned and unplanned maintenance work, and decommissioning of the device and its associated structures. The NRA was also used to assist in the development of the operational plans for the device. 

NRAs performed for port and harbour authorities within the UK and internationally are project specific and applies to the operations within the harbour which includes bathymetry within harbour limits, berthing locations, communication between vessels and the harbour’s vessel traffic service, navigation systems installed, pilotage, and towage operations. 

 Saudi Arabia

We performed an NRA for a client port in Saudi Arabia as a due diligence check to the harbour’s systems and operations listed above. The due diligence checks cover a number of items such as the location of the pilot boarding station, qualifications of the pilots, tug and pilot boat masters and the respective crew, and navigation aids. 

West Coast of Canada

Another example of a related project was a due diligence exercise encompassing an NRA for a port authority on the West Coast of Canada to assess the risk arising from a proposed LPG terminal and the transport of Liquefied Petroleum Gas (LPG) by handy sized tankers through the harbour area. The due diligence review was performed on a quantitative risk assessment which calculated a location specific individual risk (LSIR). 

This was then assessed against accepted benchmarks such as frequency of marine accidents like collision or grounding and frequency of loss of containment arising from marine accidents or gas plant operations that were derived from various calculation models like Marine Accident Risk Calculation System (MARCS) and Process Hazard Analysis Software Tools (PHAST).

We have also performed and contributed to a number of Navigation Risk assessments for the Aquaculture industry, usually to support applications for the development for fish farms in new locations for licensing purposes.