Recommendations for Managing Sustainable Net Pen Aquaculture

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 in salt water.
Atlantic salmon are raised at Cooke Aquaculture Pacific net pens near Fort Ward, Bainbridge Island. (Photo credit: Lori LeVander)

Ecology is replacing the state’s 30-year old management recommendations for commercial marine finfish aquaculture (net pens). The project is in collaboration with other state agencies and the National Centers for Coastal Ocean Science (NCCOS – NOAA).

The project will deliver science-based planning tools and management recommendations to the industry, coastal managers and communities, as well as local and tribal governments. The project will add to a vital, collaborative network of expertise through an inclusive stakeholder process and transparent scientific review. It will also contribute to ensuring any future net pen aquaculture is sustainable and protects native salmon while contributing to local food production and jobs.

Planning team meeting

March 23, 2017
Washington Department of Ecology, Headquarters
300 Desmond Drive SE, Lacey (Map/Directions)

The public is invited to attend the next planning meeting in person or listen to presentations by phone. If you plan to attend in person, please come early to sign in and receive a visitor's badge.

Call in number: 641-715-0632
Access code: 542294#

Workshop materials will be available March 22 in the online project library: Planning Meetings March 23, 2017. Copying documents to your computer will provide your best viewing during presentations.

Please contact the project coordinator with questions.


Fall 2016 to Spring 2019

Geographic scope

The geographic scope of the project includes the Straits of Georgia and Juan de Fuca, Puget Sound, Willapa Bay and Grays Harbor.

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Project goals

  • Develop new management recommendations based on modern operations, sound science and public input.
  • Base recommendations on a robust stakeholder engagement process that includes listening sessions, public forums and public comment periods.
  • Create a public geodatabase that informs siting and permitting of any future commercial marine net pen aquaculture.

Project process and roles

The project process is still being defined. Please sign up to receive updates.

Core planning Team:

Ecology and other state agencies with a role in managing net pen aquaculture form the core planning team. This team will guide the project with abundant input from experts and stakeholders. Their tasks include defining the project scope and ensuring scientific and public review of products.


As the project lead, Ecology’s Shorelands and Environmental Assistance Program is responsible for organizing meetings and events, coordination of scientific review and stakeholder engagement, and final product publication. Contact the project coordinator with questions.

NCCOS Technical Team:

At the state’s request, NCCOS is assisting the planning team by providing science-based technical assistance and tools. NCCOS published the landmark science synthesis Marine Cage Culture and the Environment in 2013 and brings national and international expertise in sustainable coastal management to the project.

Frequently Asked Questions

What are commercial marine net pens?

Net pens refer to netted, in-water cages used for both commercial and non-commercial finfish aquaculture. These pens are used in both fresh and marine (or salt) water. The term “net pen” isn’t defined in state law or rule; however, state law defines “marine finfish rearing facilities” as “those private and public facilities located within the salt water of the state where finfish are fed, nurtured, held, maintained, or reared to reach the size of release or for market sale.” [RCW 90.48.220(1)] This project addresses net pens used to raise finfish for market sale. Some management recommendations may be applicable to all types of net pens.

What is Ecology's role in the management of commercial marine finfish net pens?

Ecology reviews and approves city and county Shoreline Master Programs that address shoreline uses such as aquaculture. We also administer water quality permits that require compliance with state water and sediment quality standards. Ecology is only one of several state and federal agencies that regulate and monitor finfish aquaculture.

Why are new net pen management recommendations needed?

The state's net pen management recommendations are 30 years old. Many aspects of this issue, including management practices, current science and our understanding of the environment, have changed since our current recommendations were developed. Updated recommendations are needed for the following reasons:

Shoreline Master Programs: Commercial marine net pens have been a contentious issue during Shoreline Master Programs (SMP) updates with some Puget Sound jurisdictions wanting to prohibit the use of commercial net pens. Ecology and these local jurisdictions have struggled to find agreement over SMP policies and regulations, partially because the state lacks guidance based on today’s operations, science and best management practices. Ecology’s Shorelands and Environmental Assistance Program and local governments will benefit from modern guidance that addresses current risks.

Water quality permits: Ecology’s Water Quality Program administers water quality permits (National Pollutant Discharge Elimination Permits) for the existing eight commercial net pen sites. The new management recommendations will be used in issuing permit renewals and new permits.

Market demand: Foreign imports of Atlantic salmon through the Port of Seattle are currently twice local fish farm production. This indicates an unmet demand for locally-grown salmon, whether it is grown in the wild or fish farms. Proactively updating state expertise and management recommendations will ensure the state is prepared for any future expansion of the industry, and our response is based on appropriate safeguards suitable for Washington.

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

This project is not designed to stop or promote industry expansion. This project is designed to ensure that any new facilities are sited and operated consistent with current science and modern management approaches. Industry practices, the number of shoreline users and our understanding of Washington’s marine waters have changed significantly since management recommendations were published 30 years ago.

This project will assist Ecology and other stakeholders to ensure Washington’s aquaculture is sustainable and protects native salmon while contributing to state food production and jobs.

What science is Ecology using to guide its decisions about net pen aquaculture?

Ecology has and will continue to rely on science, state and federal laws and policies, and other guidance to frame our approach regarding commercial marine net pens. In addition to individual studies we’ve reviewed from around the world (including Canada), we rely on science compendiums and landmark documents that draw conclusions from a wide selection of science – not just one perspective.

As Ecology responds to public concerns about this use, we will continue to seek out findings and improvements to build on Washington’s strong regulatory footing. We also are dedicated to being transparent with the public we serve and are working to better share the science we use.

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

Any commercial net pen operating in Washington must abide by numerous state and federal permits 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 our NPDES permit data, 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.

Scientific monitoring has shown 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.

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. Sea lice can be vectors for other pathogens, but the presence of sea lice does not necessarily result in disease or mortality. Commercial net pens in Washington do not have significant sea lice problems as reported in other parts of the world.

Sea lice thrive in higher salinity levels found more widely in the Strait of Juan de Fuca than southern Puget Sound. The 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.

The commercial industry in Washington practices an “all in/all out” type of rearing 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 also are no 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.

Do net pens contribute to the nitrogren 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, 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 business locations and private property. Tours can disrupt the 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 17,000,000 lbs. of Atlantic salmon (Salmo salar) a year. Washington salmon growers harvest and produce fresh salmon for the seafood market 52 weeks a year. Atlantic salmon grown in Washington are sold to seafood customers throughout the U.S.

Project materials

  • Project materials are shared through the Project Library as they become available. You can download the documents from the Project Library onto your computer for viewing.
  • The draft recommendations document will be shared for public review and comment.

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” into the search box for information on commercial net pens with water quality permits.

Additional net pen scientific studies and resources will be made available online 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

Planning for Sustainable Fish Farms (focus sheet)

Governor's Office for Regulatory Innovation & Assistance