“We view Headwaters, Inc. v. Talent Irrigation District,
243 F.3d 526 (9th Cir. 2001) as binding on the U.S. Army Corps of Engineers,
Northwestern Division, in the geographic jurisdiction of the U.S. Court of
Appeals for the Ninth Circuit. In that case, the court held that irrigation
canals that receive water from natural streams and lakes, and divert water to
streams and creeks, are connected as "tributaries" to those other waters. The
Ninth Circuit further held that a "stream which contributes its flow to a larger
stream or other body of water is a tributary. . . . As tributaries, the canals
are 'waters of the United States,' and are subject to the CWA and its permit
requirement." Headwaters, 243 F.3d at 533. Moreover, the court held that,
"Even tributaries that flow intermittently are 'waters of the United States.'" Id. at 534. Corps of Engineers regulations at 33 C.F.R. § 328.3(a)(5)
assert CWA jurisdiction over all tributaries to other jurisdictional waters of
the United States. In factual situations where the Headwaters precedent
applies, it would supercede any contrary conclusion that might be drawn from
previous Corps of Engineers policy statements regarding ditches.”