The definitions in this section apply to RCW 90.48.580 and 90.48.585 unless the context clearly requires otherwise.

(1) "Credible data" means data meeting the requirements of RCW 90.48.585.

(2) "Department" means the Washington state department of ecology.

(3) "Impaired water" means a water body or segment for which credible data exists that: (a) Satisfies the requirements of RCW 90.48.580 and 90.48.585; and (b) demonstrates the water body should be identified pursuant to 33 U.S.C. Sec. 1313(d).

(4) "Naturally occurring condition" means any condition affecting water quality that is not caused by human influence.

(5) "Section 303(d)" has the same meaning as in the federal clean water act (33 U.S.C. Sec. 1313(d)).

(6) "Total maximum daily load" has the same meaning as in the federal clean water act (33 U.S.C. Sec. 1313(d)).