4.2 City of Seattle Environmental Review and Approvals

Last Updated: 7-11-2017Print page

For most private development projects, the environmental review is a part of the Seattle Department of Construction and Inspections’ (SDCI’s) Master Use Permit (MUP) process and SDCI is considered the lead agency. SDCI is also responsible for the environmental review of City Council conditional uses, construction permits, full subdivisions, major institution master plans, and rezones. When work by a private entity is solely in the right-of-way and does not require one of the SDCI decisions listed above, the environmental review will be performed as part of the SDOT Street Improvement Permit (SIP) or another required permit(s).

City of Seattle Environmental Permits/Approvals

The State Environmental Policy Act (SEPA), RCW Chapter 43.21 C, requires governmental agencies to consider the environmental impacts of a proposal before making decisions. The environmental impacts of certain private development proposals must be assessed by the City per SEPA regulations under Chapter 25.05 and SEPA policies under Chapter 25.05.902. The level of documentation required and threshold determination to comply with SEPA are dictated by the type of impacts a project may have. There are three levels of documentation:

  • Categorical exemption: State and City SEPA regulations list certain types of projects presumed to have minimal or no impacts. A SEPA review is not required for these exempt projects. However, certain state and federal permits may require a letter or memo indicating a project is exempt. SEPA exemptions are listed in SMC 25.05.305 and SMC 25.05.800 and for SDCI permits are further clarified in SDCI Director’s Rule 29-2015.
  • Determination of non‐significance (DNS): During the review of a project under SEPA, impacts from a proposal may be limited to those which are fairly minor in scope or otherwise are not considered to be significantly adverse. This determination may be made after reviewing a SEPA Environmental Checklist and other supporting documentation. The City SEPA policies (SMC 25.05.902) and departments may allow for mitigation from potential adverse impacts. SEPA checklist requirements can be found in SMC 25.05.315 and are described in more detail below.
  • Determination of significance (DS): When City review of a proposal determines that expected adverse impacts may be significant, a Determination of Significance may be made by the City, requiring the preparation of an environmental impact statement (EIS). A description of SEPA EIS requirements can be found in SMC 25.05.400 through 25.05.460.

Filling Out the Environmental Checklist

If a project in the right-of-way is not categorically exempt, an Environmental Checklist must be filled out and submitted by the applicant at the time of the permit application, so that SDOT can review the project for compliance.

If the environmental review for a project has been completed by another City department or by a different governmental agency, a copy of the threshold determination and the Environmental Checklist – or the draft and final EIS – must be made available to the SDOT project manager. A copy of the threshold determination and EIS, if any, must also be submitted to SDOT prior to 60% Complete SIP Approval to ensure transportation impacts and mitigation are identified.

Applicants must fill out the Environmental Checklist accurately and completely, acknowledging potential impacts, including those associated with demolition, grading, and construction (temporary as well as permanent). Measures that an applicant plans to take to mitigate adverse environmental impacts associated with a project should be discussed under the appropriate element(s) of the environment.

The completed checklist must be dated and signed by the applicant. Future development proposals related to the project should be discussed even if details are not fully established. This will ensure that the applicant does not need to go through an additional environmental review and appeal period later in the process. However, discussion of future development proposals in the checklist does not exempt an applicant from independent SEPA review of a future project, if that project is over SEPA thresholds. In most circumstances, the review for the total proposal must be completed before any permits can be issued. The more complete the information provided, the faster the review of the project can be conducted. If the information submitted is incomplete or if additional information is needed to make an accurate analysis of the environmental impacts of a project, the applicant will be required to furnish further information. Contact the project manager for more information on these requirements.

The sections below are explained in more depth due to commonly asked questions through previous SEPA projects.

Transportation Impact Analysis

As part of the environmental review process, transportation impact analyses (TIA) or parking demand studies may be required to document a project’s transportation or parking impacts. A TIA typically estimates traffic volumes that a proposed project would generate, and compares the operating conditions of nearby intersections or roadway segments with and without the additional traffic. A TIA may also estimate potential traffic queues, examine any outstanding safety issues, and assess the impact of the project on transit, freight, pedestrian, and bicycle facilities.

Projects may also be required to demonstrate that they satisfy transportation concurrency requirements established under the Washington State Growth Management Act. The City uses a system‐wide method as a basis to assess the performance of the transportation system. Because buses are the primary form of transit ridership in the city and buses operate on the arterial system, the City has chosen to use the same method to measure the level of service for the arterial system generally and the transit system. The City is currently also considering alternative methods of level of service standards that consider all travel modes. Refer to the Comprehensive Plan, Transportation Element for additional information on level of service standards.

A SEPA review may result in transportation mitigation measures consistent with SEPA policies such as full or partial contributions to transportation system improvements for new or upgraded traffic signals or roadway modifications.

Hazardous Materials Analysis

Section B.7.a. of the environmental health section of the SEPA checklist requires the disclosure of any environmental releases or potential releases to the environment affecting public health. These releases would include any toxic or hazardous materials that may be caused by, or encountered during a proposed project. This includes known or suspected contamination on private property and potential migration into the right-of-way. This section of the checklist should summarize any analyses that have been completed, evidence of past contamination, or reports indicating the site has been contaminated. Phase I and/or Phase II Environmental Site Assessments, property record searches, communications with the Washington State Department of Ecology, and cleanup action reports should accompany the checklist. The City restricts installation of underground storage tanks in the right-of-way. For more information see Director’s Rule 1-2012.

Environmental Critical Areas

The City has designated Environmental Critical Areas (ECAs) throughout the city. These areas are considered environmentally sensitive and include landslide-prone, liquefaction-prone and flood-prone areas, wetlands, riparian corridors, steep slopes, fish and wildlife habitat conservation areas, and abandoned landfills. For more information see the City Regulations for Environmental Critical Areas (SMC 25.09) and SDCI’s GIS.

Historic and Cultural Resources Preservation

The historic and cultural resources preservation section of the SEPA checklist requires responses about a proposal’s potential impacts on historic, archaeological and cultural resources within or adjacent to the right-of-way. Policies guiding preservation of these resources, special historic districts, and sites of archaeological significance are found within the City Historic Preservation Policy (SMC 25.05.675H). Evaluation of impacts to these resources is also subject to SEPA review. Documentation of these resources and potential impacts are required in Section B.13 on the checklist and are needed as a component of an approval to alter certain cultural, historic or archaeological resources in the City.

Landmarks and Historic District Boards/Commissions Approvals

When a project would modify a designated city landmark (such as a building, park, or other feature) or make above-grade physical changes in a historic district (such as Pioneer Square or the International District), a Certificate of Approval is required from the Seattle Department of Neighborhoods (DON). This review involves public notice and presentations to a review board by the City, and can result in changes to the project design to make it more compatible with the landmark of concern. If a project location is adjacent to a designated landmark, DON staff must be consulted and may request changes to the project design. Review by a board is not required, although DON may request such review at its discretion.

Shoreline District

A shoreline substantial development permit or a shoreline exemption are required through SDCI for work within 200 feet of the Shoreline Master Program shoreline district. The shoreline district includes Elliott Bay, Lake Washington, Puget Sound, the Ship Canal, Lake Union, the Duwamish River, Green Lake, associated wetlands, and all land within 200 feet of these water bodies. The Shoreline Master Program includes rules and restrictions in these areas for uses, environmental impacts, public access, views, and height. For more information see the Shoreline Master Program Regulations (SMC 23.60A) and SDCI’s shoreline permit requirements.