EIS Process

Enterprise Services, as the lead agency under the State Environmental Policy Act (SEPA), determined that there were probable significant adverse impacts from construction and operation of a long-term management project. Thus, an Environmental Impact Statement (EIS) is required to evaluate potential significant environmental impacts (and benefits), and to inform stakeholders of reasonable alternatives, including mitigation measures that would avoid or minimize adverse impacts or enhance environmental quality. 

Neither short-term actions nor a long-term management alternative could be implemented until the EIS was completed. 


The first step in the development of an EIS is called scoping. During scoping, agencies, tribes, local communities, organizations, and the public may comment on factors to be analyzed and considered in the EIS.

Specifically, the scoping process collected input on the following topics:

  • Reasonable range of alternatives
  • Potentially affected resources and areas of impact
  • Potential measures to avoid, minimize, and mitigate effects of the proposal

During the scoping period, Enterprise Services and its consultants hosted public meetings, both in-person and online, and solicited comments from the public.

Scoping concluded on Nov. 13, 2018. Over the 48-day scoping comment period, the project received more than 900 individual comments from 271 separate submissions. Thank you again, to everyone who participated in meetings and submitted comments.

The Scoping Report, which summarizes comments received, provides an overview of the project and the primary alternatives to be considered, and describes the scoping process was issued on Feb. 1, 2019.

Third-Party Review

Enterprise Services committed to ensuring the technical analyses informing the EIS were conducted using industry-recognized best practices and included a reasonable level of analysis to allow for the comparison of alternatives. Although not required by SEPA, Enterprise Services engaged independent third-party experts to objectively review the proposed methodologies and findings for three technical disciplines: water resources, hydrodynamic and sediment transport, and economics. These disciplines were selected based on feedback received during scoping, the complexity of these analyses, and their particular importance to the evaluation of the alternatives. 

These methodologies are available to the public. Although not typical for during a SEPA process, Enterprise Services is electing to share these methodologies in the interest of transparency. For more information please review Enterprise Services’ document describing the third-party review process.

Draft EIS

The Draft EIS was issued for public comment on June 30, 2021. The extended, 62-day comment period concluded on Aug. 29, 2021. The Draft EIS provided an objective summary of long-term management alternatives, the impacts and benefits of the alternatives over a 30-year time horizon, short-term impacts during construction, and potential mitigation measures. It included additional information that was considered in the decision-making process, including planning-level costs, input from engaged governmental and agency partners, and permits and approvals that would be required to implement a preferred alternative. 

Likely Preferred Alternative

A top theme from the more than 850 comments on the Draft EIS was that a funding and governance approach for long-term maintenance must be identified. This was the primary objective of the Funding and Governance Work Group (FGWG). The FGWG agreed to reconvene to advance a final shared long-term funding and governance approach only after a preferred alternative was identified.

In March 2022, the EIS Project Team and Enterprise Services evaluated the alternatives against a range of technical criteria using the process outlined in Chapter 1.0, Section 1.12 of the Draft EIS, and considered input from engaged stakeholders on the ability of each alternative to achieve long-term support.

Following this evaluation, Enterprise Services identified the Estuary Alternative as the likely preferred alternative.

After the FGWG confirmed and memorialized the approach to long-term funding and governance, those findings could be incorporated into the EIS and relevant analyses. The findings became part of the Final EIS (with other updates and responses to comments on the Draft EIS).

It is important to note that identifying a likely preferred alternative was not a final decision. Designation of a likely preferred alternative prior to issuance of the Final EIS did not restrict final decisions.


The EIS Project Team updated the technical analyses in response to public comments on the Draft EIS, and prepared the Final EIS, which was issued on October 31, 2022.

The Final EIS is based on the Draft EIS and includes a comment response summary and confirms the preferred alternative and long-term funding and governance approach for the project.

Enterprise Services identified the preferred alternative in the Final EIS following an evaluation of the management alternatives against six selection criteria. The criteria as described in the EIS include the following:

  • Performance against project goals
  • Other environmental disciplines with significant findings (impacts or benefits)
  • Environmental sustainability
  • Economic sustainability
  • Construction impacts
  • Decision durability

The Draft and Final EIS provided the information needed to complete the evaluation against the selection criteria for five of the six criteria. For Decision Durability, Enterprise Services solicited input from the Squaxin Island Tribe, local governments, and the Community Sounding Board, on which alternatives were likely to achieve long-term support.

Enterprise Services worked with an interdisciplinary team of consultants to prepare the EIS. The interdisciplinary team has specialty experience in EIS development and expertise in the disciplines that were studied.


After an EIS process, the selected alternative moves into a design and permitting phase. The conceptual designs developed during the EIS are advanced to final design for each of the project components. Permits are obtained from federal, state, and local agencies; these are needed before construction can begin. Enterprise Services would maintain stakeholder involvement throughout this project phase.