UPDATE: Ecology's new website will be live on Monday morning! Our official web address will be https://ecology.wa.gov

SEPA and Climate Change

We are facing a global problem. We need to approach the problem from both directions – reducing our contribution to climate change and preparing for the effects. We need to work together – business, government, citizen groups, individuals, tribes, neighboring states and trading partners – to be effective. Each day in our state, projects are proposed that could either add to the emissions of greenhouse gases, or locate development in areas that in the future could well be underwater, or subject to flooding not seen before.

State agencies, city and county planning departments, and other public entities use SEPA to evaluate the environmental impacts of a proposal. Many states and local governments have developed policies, regulations, and guidance on how, where and when to address climate change in their environmental review processes.

Ecology acts as the lead agency for the State Environmental Policy Act (SEPA) review on many projects and rules.

We have developed guidance for our agency on how SEPA should be used to assess greenhouse gas impacts. We intend to periodically evaluate and make improvements to the guidance.

We're planning our first update and will begin by gathering information about new methods used by local, state, and federal agencies to evaluate greenhouse gas pollution. As we make guidance updates, we'll coordinate our current work, which includes rules and projects we act as the lead or co-lead SEPA agency on, to be consistent with new guidance.

Frequently asked questions

Here are some answers to frequently asked questions to help provide background on SEPA and Climate change:

Emissions Calculation Tool

When quantifying new emissions that are caused by the project, proponents should use accepted protocols and emissions factors such as those outlined in Attachment 2. We have also developed a simple tool that will be helpful in quickly estimating emissions from specific projects. It is available online: SEPA Greenhouse Gas Calculation Tool (excel spreadsheet)

Additional information and resources

Other related documents


For questions or comments concerning SEPA, please email the SEPA Unit or call (360) 407-6922.