Fast-ferry trials enter second phase
June 12, 2008 · Updated 12:50 PM
The first phase of a shoreline study along Rich Passage to determine the feasibility of reviving fast-ferry runs from Bremerton to Seattle is complete, and engineers are now preparing for the next phase.
According to Phil Osbourne of Pacific International Engineering, the group conducting the Seattle-Bremerton Fast Passenger-Ferry Study for Kitsap Transit, the second phase of work will include more fast-ferry trials, along with potential re-nourishment of the shoreline, which involves adding sediment and other materials to affected beaches.
Osbourne, who spoke at the last Port Orchard City Council meeting on Feb. 27, said his group began the project because there was significant interest in reviving the fast ferries, which were halted due to complaints from property owners, who ultimately filed a lawsuit.
The conclusion is that the state-run ferries had a substantial impact on the beaches, making the condition of the beach unacceptable to the property owners, he said, showing a slide of a particularly affected area near Point White on Bainbridge Island.
Osbourne said the study is focusing on the wakes created by the boats. While wakes are less of a problem in deep water, he said in Rich Passages narrow and shallow areas the waves created get amplified by the bottom topography and tidal currents, wreaking havoc on the shoreline.
Osbourne said his group began the study by making models of different wakes and how they behave, which would eventually allow them to predict how different vessels at different speeds would affect the shoreline areas.
Once the model was created, he said his group could plug in the specifics and speeds of vessels they were considering for the route and see if any would meet their criteria for low wakes.
Osbourne said while none of the boats tested including the M/V Spirit would be perfect as is, he said, I think were on the right track with the foil-assisted catamaran, such as the Spirit. I think this type of vessel could be optimized quite a lot (to improve the wakes).
Along with determining modifications that could be made to boats, his group will also be evaluating how much of an impact beach nourishment may have on the shoreline.
Some of the beaches have been damaged to such a point from increased ferry and other boat traffic that they need restoration or other enhancement in order to be able to cope, Osbourne said, explaining that so far his group has identified four locations along the route for trial placements: Point Glover in Manchester, Enetai Beach in East Bremerton, and both Point White and Pleasant Beach on Bainbridge Island.
Osbourne said the beach re-nourishment would involve adding about one cubic yard of sediment material per linear foot of beach, then tracking the status of the beach.
To accomplish that, his group will attach radio frequency tags to rocks, allowing the scientists to monitor where and when the beach particles move and track them through time.
Kitsap Transit Executive Director Dick Hayes then addressed the council, explaining he was visiting each community to inform them of the next phase of the study because his agency needed to complete an environmental approval process before beginning the testing.
Also, hopefully some day we will be running high-speed boats from downtown Port Orchard to Seattle, and you will certainly have a stake in that, Hayes said.
Five public meetings will also be scheduled in the communities affected, including one in Port Orchard, that will be announced later this month.