A tidal gate with a $250 million price tag could be the answer to rising sea levels, according to a presentation at a recent city meeting.
The gate could be an alternative to rebuilding higher sea walls, City Councilwoman Nancy Gardner told members of the Corona del Mar Residents Association at the group’s January board meeting.
“It would not be cheap, but from what everyone has learned, the other thing would not be cheap either,” she said.
The Newport Beach Tidelands Management Committee heard the presentation at a meeting earlier this month, according to officials and an online agenda.
City Councilman Mike Henn told the City Council at Tuesday’s meeting that the gate would be a “barrier across the entrance” and would be similar to methods used in Amsterdam and Venice.
“It’s good to hear these kinds of presentations to be sure,” he said.
Dale Berner, president of the Oakland-based Ben C. Gerwick Company, described the conceptual idea of a tide control structure in the harbor entrance channel at the committee meeting held Jan. 16.
“The presentation was very informative, and exposed the group to alternate ideas to the sea level rise question,” said Chris Miller, the city’s harbor resource manager, in an email. “The ballpark, general number was in the $250 million range, +/- $50 million,” his email said.
The presentation included images of projects in cities including New Orleans and Houston and described how completed projects can be floated into place. The presentation also described how various flaps and gates can rise as needed from the bottom of the channel, and how the gates can be partially raised during rising tide to form a “salinity barrier” that protects against “the intrusion of dense, salt water.”
The presentation was informational only, and there are no further meetings scheduled to discuss the gate further at this time, Miller said.