Cypress Island Atlantic salmon pen break: Track the response and recovery effort on the joint-agency page.

Guidance for managing commercial marine net pens of Atlantic salmon

Net pens refer to netted, in-water cages used for both commercial and non-commercial finfish aquaculture, in both fresh and salt water. This project only addresses commercial pens of Atlantic salmon in salt water.
Atlantic salmon are raised at Cooke Aquaculture Pacific net pens near Fort Ward, Bainbridge Island. (Photo credit: Lori LeVander)

Washington has eight commercial marine fish farms growing Atlantic salmon (Salmo salar) in net pens. The state’s management recommendations for these facilities date back more than 20 years – and need replacement due to changes in operations and our scientific understanding. Now the state is working to develop new guidance.

The project is led by Ecology in partnership with the state departments of Agriculture and Fish and Wildlife, with technical assistance provided by the National Centers for Coastal Ocean Science. Staff of the Port Gamble S’Klallam Tribe and Northwest Indian Fisheries Commission are advising the state in this effort. The project aims to:
  • Build the state’s knowledge and expertise about the commercial net-pen industry in the United States, Canada and other locations.
  • Deliver science-based planning tools to local and tribal governments, state and federal agencies, and the industry.
  • Contribute to protecting threatened native salmon in Puget Sound and our coastal estuaries.
  • Engage the public in fact-finding and address their questions and concerns about this use.

Project goal

By Spring 2019, Washington’s need for clear, updated information will be addressed by developing new guidance and a spatial screening tool for commercial, marine net pens of Atlantic salmon in Puget Sound, Willapa Bay and Grays Harbor.


Fall 2016 to spring 2019

Project scope

Project area: Puget Sound and its complex system of waterways, and the coastal estuaries of Grays Harbor and Willapa Bay are included in the project area. Certain effects of commercial net pens that are likely to occur beyond this area will be discussed in the final document. Project Area Map

Types of net pens and fish: The project addresses commercial marine net pens of Atlantic salmon (Salmo salar). It does not address net pens rearing herring for bait, fisheries enhancement pens rearing Pacific salmon for release, freshwater pens, or species other than Atlantic salmon.

Relationship to the aquaculture industry: The project is not designed to stop, deter, promote or expand commercial finfish aquaculture in Washington. The state is working to identify modern management practices, especially when it comes to siting and operating potential new facilities or renewing existing permits or authorizations.

Relationship to regulations: The project will not directly change laws or regulations but will deliver guidance to the industry, local and tribal governments, state and federal agencies, and the public. Each regulatory agency will make an independent determination if changes to their legal authorities are needed.

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Project team

Planning Team: The state departments of Agriculture, Ecology and Fish and Wildlife are on the Planning Team and each have an important role in managing aquaculture in Washington. The Team guides the project with input from other state agencies, tribal advisors, technical experts, and interested parties.

Project Coordinator: Ecology’s Shorelands and Environmental Assistance Program organizes meetings and public engagement, coordinates work flow, and is lead on the development of deliverables for Planning team review and approval. Contact the project coordinator with general questions. Contact the communications manager with media inquiries.

Federal technical assistance: At the state’s request, the National Centers for Coastal Ocean Science (NCCOS) is assisting the Planning Team by providing science-based technical assistance to the project, including research and development of draft products. In 2013, NCCOS published the landmark science synthesis Marine Cage Culture and the Environment. This partner brings national and international expertise in sustainable coastal management to the project.

Tribal advisors: Staff of the Port Gamble S’Klallam Tribe and Northwest Indian Fisheries Commission are advising the Planning Team. As co-managers of the state’s fisheries resources, tribal governments are important partners in the project – ensuring treaty rights and fisheries resources are protected.

Frequently Asked Questions

Will this project promote expansion of commercial finfish aquaculture in Washington?

The project is not designed to deter, stop, promote or expand commercial finfish aquaculture. The project is designed to ensure that any new facilities are sited and operated consistent with current science and modern management approaches, and existing facilities are operated consistent with proven best practices.

What new information if the Planning Team using to develop the new management recommendations?

Team members are involved in two studies that will inform the final recommendations: Ecology and NCCOS are compiling a summary of National Pollutant Discharge Elimination System (NPDES) permit data for existing pens, and Fish and Wildlife is conducting a fish health assessment.

The Planning Team members are relying on science and local knowledge to build on Washington’s strong regulatory footing for commercial marine net pens. In addition to reviewing individual studies representing multiple perspectives, we are reviewing science compendiums and landmark documents that draw conclusions from a large body of research.

The Planning Team is inviting the public to submit scientific studies and papers for their consideration and providing a public comment period. In addition, the Team will select scientific and technical experts to assist in preparing the public draft and ensuring the guidance reflects the weight of the evidence.

Do net pens affect the water or sediment quality of Puget Sound

Scientific monitoring has shown the existing Puget Sound net pens have temporary impacts on sediment quality and benthic life, including directly under the pens. Once a net pen is moved or closed, the substrate recovers to pre-existing conditions in two to 12 months. Washington’s current commercial net pen operator, Cooke Aquaculture Pacific, voluntarily fallows (temporarily closes) the existing net pens after every harvest cycle to reduce impacts.

To operate in Washington, all commercial net pens must comply with numerous local, state and federal requirements to protect the environment. Since 1991, commercial net pens have been required to comply with NPDES (National Pollutant Discharge Elimination System) permits issued by Ecology. Based on over 20 years of permit monitoring and reporting records, the industry has a good track record of complying with state water quality and sediment standards. Data is available online in our PARIS database. Enter "Icicle Acquisition" into the search box for information on commercial net pens with water quality permits.

Do net pens in Washington have sea lice problems?

Sea lice naturally exist in the wild populations of native Pacific salmon and other fish and these sea lice spread to net pen fish. While, sea lice can be vectors for other pathogens, their presence does not necessarily result in disease or mortality. Commercial net pens in Washington do not have significant sea lice problems.

Sea lice tend to thrive in higher salinity levels more widely found in the Strait of Juan de Fuca than south Puget Sound. Significant freshwater flows from large rivers and the correlation of floods with vulnerable stages of the sea lice lifecycle can reduce the presence of sea lice near the mouth of major rivers.

In Washington, the commercial industry uses an “all in/all out” type of operation. This means the industry puts a single age group of fish in a set of pens then harvests that single age group 12-24 months later. Fallow periods of a few months then occur where the pens are emptied and removed from the water. This disrupts the life cycle of any sea lice present.

Can Atlantic salmon breed with native Pacific salmon?

There is no evidence that Atlantic salmon can successfully interbreed with Pacific salmon, even in ideal laboratory conditions. There are no known self-sustaining, wild populations of Atlantic salmon in Washington’s waters. According to state and national fisheries experts responsible for protection and recovery of wild salmon, the risk is very low that an Atlantic salmon population could establish in Washington waters.

While Washington has eight marine commercial net pen operations raising Atlantic salmon, is this practice allowed in other states on the West Coast?

Each state’s approach to finfish aquaculture and Atlantic salmon differ. For instance, Alaska prohibits farming or hatchery operations involving Atlantic salmon. Oregon does not prohibit Atlantic salmon aquaculture while California has adopted a more complicated approach to finfish aquaculture in general and Atlantic salmon specifically.

What do Alaska, California and Oregon allow?

Alaska does not issue permits for farming or hatchery operations involving Atlantic salmon. State law prohibits the growing or cultivation of finfish in captivity for commercial purposes. There are some exceptions for state fishery rehabilitation, enhancement or development; non-profit entities that hold a salmon hatchery permit to sell naturally-spawning fish or surplus salmon eggs; and aquarium fish.

California prohibits the spawning, incubation or culture of any species of salmon, transgenic fish or exotic finfish species in the state waters of the Pacific Ocean. State regulations are silent about land-based facilities or rearing Atlantic salmon in fresh water. Under state law, however, Atlantic salmon are a restricted species in the Smith River watershed.

Oregon allows Atlantic salmon aquaculture. In 2013 and 2015, however, state legislative committees considered bills to prohibit Atlantic salmon aquaculture but both measures failed to make it out of committee. In addition, for almost 50 years the Oregon Department of Fish and Wildlife had operated a fishery for a landlocked variety of Atlantic salmon in Hosmer Lake but the state terminated the program in 2015 due to lack of public interest in the fishery.

Do net pens contribute to the nitrogen problems in Puget Sound?

Ecology’s Puget Sound studies show that net pens are not a significant source of nitrogen in Puget Sound. Major nitrogen contributions come from ocean currents, the atmosphere, natural sources, waste water treatment plants, urban sources, agricultural sources, septic systems and even Puget Sound sediments.

Can I visit a commercial marine net pen?

Commercial net pens are active maritime businesses and private property. Tours can disrupt daily business activities due to safety precautions necessary to protect visitors and to protect food fish from disease or contamination. The current owner of the eight Puget Sound net pens, Cooke Aquaculture Pacific, values community relationships and is open to offering scheduled tours to interested parties.

How much Atlantic salmon are raised in Washington, and where are they sold?

Washington has the largest marine finfish aquaculture industry in the U.S. with eight marine farms producing approximately 17 million pounds of Atlantic salmon annually. Washington salmon growers harvest and produce fresh salmon for the seafood market 52 weeks a year.

Project materials

Below are two documents that were written in the 1980s and 1990s by state agencies. This project will refresh the information contained in these documents based on today’s science and operations.

In addition, Ecology's Water Quality Program has National Pollutant Discharge Elimination System (NPDES) permit data for the existing commercial net pens in Puget Sound. Available online: Water Quality Permitting and Reporting Information System (PARIS) Database. Enter “Icicle Acquisition Inc.” into the search box for information on commercial net pens with water quality permits. Map of existing commercial net pens of Atlantic salmon in 2017.

Additional net pen scientific studies and resources will be made available through the Project Library or this website as time and resources allows.

Staff contacts

Cedar Bouta
Project Coordinator

Curt Hart
Communications Manager (for media inquiries)


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Shellfish Safety Hotline (Washington State Department of Health)

Shellfish Aquaculture Debris Hotline (Pacific Coast Shellfish Growers Association)

WA Shellfish Initiative (PDF)

Shellfish Interagency Permitting Team Results

State Guidance for Commercial Net Pens of Atlantic Salmon (focus sheet)

Governor's Office for Regulatory Innovation & Assistance