Aquaculture America 2024

February 18 - 21, 2024

San Antonio, Texas

REDUCING RISK IN DESIGN AND OPERATION OF OCEAN AQUACULTURE

Mr. Aland, PA

 

DNV – Det Norske Veritas

Veritasveien 1, 1363 Høvik, NORWAY
e-mail: per.arild.aland@dnv.com

 



INTRODUCTION

We see a growing trend that mariculture is growing out of sheltered, near-shore areas and moved to locations further offshore. There are several advantages applying this solution. Better fish welfare, less conflicts with interests in the ocean space as well as possibility to scale up output volume without compromising environmental sustainability are some of them. As the world’s population grows, the options for producing enough food are becoming limited. The oceans offer a vast opportunity to meet this demand with sustainable, safe and efficient offshore fish farming.
Adding safety to offshore fish farming projects is mainly ensured by providing uniformity, transparency, and predictability and thereby reducing project risk. We need to be ensured that facilities for aquaculture can handle harsh environment and still contain the fish safely.

MAIN APPROACH

The main areas of concern when it comes to ensuring safe and reliable offshore fish farming units may be categories into: Asset integrity, personnel safety, fish welfare and prevention of fish escape.

Asset integrity includes structural strength, stability, mooring, technical arrangement, and solutions on board together with reliability of essential equipment installed.

Personnel safety is mainly addressing arrangement for emergency escape and fire safety. This included lifesaving appliances, launching equipment and similar as well as fire detection and -extinguishing. It is common to apply well know maritime codes as acceptance criteria for personnel safety. SOLAS is a good example followed by local flag- or shelf states interpretation of requirements embedded in this maritime code.

Fish welfare and requirements related to this varies depending on local authorities. It is essential to verify the reliability of technology utilized to monitor environment of the fish. Instrumentation indicating oxygen level, temperature, salinity, turbidity is subject for special attention. Maximum acceptable level of biomass is also a crucial parameter that needs to be monitored.

Fish control or prevention of escape is the main function of a fish farming unit. Structural integrity of net system and ropes together with capability of fish transfer systems are crucial items in fish control. Flexible net systems utilized in rigid high volume steel fish farming installation has proven to be exposed to fatigue and need to be attended to in particular. Wear and tear of net due to cleaning and handling is also a concern. Several of reported incidents related to fish escape happens while handling of fish – for example crowding due to de-licing or transfer. Equipment contributing to these operations needs to be specially attended to.

The four different items are considered equally important for safe and sustainable fish farming offshore. These elements are also closely interconnected where integrity of one may support several others.

Photo Salmar Ocean

CONCLUSION

There is a significant potential to utilize competence from traditional offshore and maritime industry to help operators of exposed fish farming units to identify operational risks by applying technical rules and requirements from classification. As opposed to the offshore oil and gas industry, classification may not be obligatory in aquaculture, but it turns out that many developers and operators nonetheless choose to follow class requirements and recommendations.

Combining the well-known classification concept from maritime industry with balanced aquaculture-based requirements provides a robust and cost-efficient solutions to reducing risk in operation of offshore fish farming installations.