The Ninth Circuit has expanded the reach of Rapanos to include seasonally intermittent streams. In U.S. v. Moses, the Ninth Circuit recently affirmed a criminal conviction of an Idaho man for dredging and dumping material into an intermittent stream without a permit under the Clean Water Act. Moses, a developer, was warned by the Army Corps of Engineers that his rerouting and reshaping a channel to control its flow required a permit. Moses contended that the portion of the creek that he worked in did not constitute a water of the United States as it was dry for 10 months out of the year.

The question before the Court was whether a seasonally intermittent stream that ultimately empties into a river that is a water of the United States can, itself, be a water of the United States. The Court answered in the affirmative, citing its own opinion in Headwaters, Inc. v. Talent Irrigation Dist., 243 F.3d 526 (9th Cir. 2001), which held that canals can be “waters of the United States” even when there is no exchange of water with local streams and lakes. The Court stated that the controlling test for CWA’s jurisdiction is the “significant nexus” test announced by Justice Kennedy in his concurring opinion in Rapanos instead of the plurality opinion of Justice Scalia.

Download U.S. v. Moses opinion (PDF: 77KB).