At This Salmon Farm in Bergen, Water Is Recycled—and the Fish Grow Even Better

On the outskirts of Bergen, a seemingly unremarkable building houses nearly 3,000 tons of salmon. If you step inside, your first reaction might be: Why isn’t there the sound of flowing water? That’s because the water circulates almost entirely in silence between pipes and tanks. Operated by a major Norwegian aquaculture company, this farm is the RAS (Recirculating Aquaculture System) model that the global aquaculture industry is currently buzzing about.

Here, water is “reused.” Water from the fish tanks passes through biological filters, aeration devices, and temperature control systems before flowing back in, with a recycling rate exceeding 95%. An on-site operations manager offered an analogy: “You can think of it as creating a small environment for the fish that maintains constant temperature, oxygen levels, and water clarity. Wind and snow outside have no effect on the conditions inside. When the fish are comfortable, they grow faster and mortality rates are lower.”

RAS is not a new concept, but it has developed particularly rapidly in recent years. According to FAO data, global facilities of this type have increased by more than 30% over the past three years. The reasons behind this trend are well known: increasingly stringent environmental regulations, the growing scarcity of freshwater, and rising costs associated with traditional earthen pond aquaculture.

Returning to this salmon farm, its greatest appeal actually lies in several tangible advantages.

The most significant, of course, is water conservation. Recirculating 95% of the water means only a small amount of fresh water needs to be added daily, which significantly reduces water costs given current rates.

Secondly, very little wastewater is discharged, and what is released is treated to easily meet Norway’s local environmental standards—a major plus with regulatory authorities, as it protects the environment while avoiding unnecessary complications.

Additionally, automated sensors and an AI-driven monitoring platform keep a close eye on key parameters such as dissolved oxygen, ammonia nitrogen, and water temperature. Since staff don’t need to enter the operational area frequently, the risk of fish disease is also reduced.

Finally, the facility operates year-round. Whether it’s the polar night or a mild winter, the fish in the tanks continue to grow as they should; there’s no need to “wait for the right season to stock the tanks.”

An aquaculture expert from a renowned European university specializing in fisheries visited the facility in person. She put it bluntly: “The initial investment is certainly substantial, but the numbers add up. We save on water costs, we save on medication costs, and the quality of the fish has improved. To put it simply, we’re not throwing money into the water—we’re making every penny grow into fish.”