June 16th, 2014, by Charlie Bermant, The Seattle Times

A device attached to the hull of a Port Townsend-Coupeville ferry will help scientists collect data on low-oxygen water and ocean acidification

PORT TOWNSEND — The state ferries system has attached a device to the hull of the MV Salish on the Port Townsend-Coupeville route to provide data on low-oxygen water and ocean acidification from Admiralty Inlet.

“This will help us understand Puget Sound much better,” said Sandy Howard, a Department of Ecology spokesperson.

“It provides a new piece of information that we never had before and will allow us to monitor current, velocity, temperature and the flow of fresh and salt water on a long-term basis.”

During a recent servicing, Washington State Ferries crews attached the sensor, an acoustic Doppler current profiler, to the bottom of the Salish, which makes 11 daily crossings between Port Townsend and Coupeville on Whidbey Island.

The sensor gathers data during the crossings of the area known as Admiralty Inlet, or Admiralty Reach, the gateway to the Puget Sound, where salt and fresh water merges.

The project is a partnership among Ecology, Washington State Ferries and the University of Washington.

It is supported by a $261,000 grant from the Environmental Protection Agency.

The rudder-shaped device, which extends about 40 inches from the middle of the hull, both stores and transmits data, according to Cotty Fay, chief naval architect and manager of vessel design for the ferry system.

The device is expected to last at least five years and will cause the ferry to have a “very small” slowdown of about 0.5 percent, Fay said.

“Every tide is different than the one before,” Fay said. “Over a long period of time, we will get a profile of how the water moves in and out of Puget Sound.”

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