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Washington State Environmental Policy Act


Washington’s State Environmental Policy Act (SEPA) was enacted in 1971 to ensure that state and local agencies considered effects on the environment during their decision-making processes. As part of a general effort to create a comprehensive statutory review scheme, SEPA requires the identification and evaluation of possible impacts a government proposal may have on the environment.

SEPA's purposes are:

  • To declare a state policy which will encourage productive and enjoyable harmony between humankind and the environment;
  • To promote efforts which will prevent or eliminate damage to the environment and biosphere; and [to]
  • Stimulate the health and welfare of human beings; and
  • To enrich the understanding of the ecological systems and natural resources important to the state and nation.

RCW § 43.21C.010