APL-UW is using wave buoys to measure the wakes of Washington State DOT car ferries as they transit through Rich Passage. The objective is to assess the effectiveness of the speed reduction protocol through the passage, which is intended to minimize the vessel wake and minimize any subsequent changes to the shoreline.

APL-UW is also measuring the tidal currents to evaluate changes in the wake propagation during strong flows. The measurements include a control case of wakes measured outside of the inlet, when the vessels travel at full cruising speed. The wave buoys are deployed for a few hours at a time, during which the individual wakes of ferries are recorded onboard the buoys. Buoys are recovered and the data are processed along with vessel track and speed logs from the car ferries.

The purpose of the study is to continually monitor the shoreline and wave heights to ensure ferry operations are not impacting the shoreline.

Measurements are being taken during the weeks of 15 September and 17 November 2014. More measurements will be taken as funding allows.