PROJECT ALERT NOTICE (OR) Atmospheric River Impacting rivers in Northwest Oregon

Date: Wed, 10 Dec 2025 11:25:19 EST

Summary: Oregon Staff Responding to Atmospheric River Impacting rivers in Northwest Oregon.

A significant atmospheric river continues to impact northwest Oregon today, although the most intense precipitation has passed for the state. December 10, we have four crews deployed for flood-related data-collection work. In addition, staff are conducting sediment sampling at a critical reservoir in support of the ongoing drawdown study, as well as completing scheduled site visits for streamflow measurements and sensor checks at water-quality sites in the affected areas. One crew is also repairing a down gage on the Columbia River.

Currently, five sites between the coast and the Portland urban area are in flood stage, and many urban sites crested last night. Sites cresting today appear to be peaking slightly lower than forecasted.