Thursday, October 30, 2014

The Harbor Report: Serious stuff: rising seas and harbor protection




Proposed Tide Gate at entrance of harbor.


By Len Bose
June 6, 2014 | 3:04 p.m.

Last week, I attended the Tidelands Management Committee meeting, where the main two topics were protecting Newport Harbor from rising sea levels and replacing the Balboa Island seawalls.
Assistant city engineer Robert Stein gave both presentations, which lasted close to 2 1/2 hours.
Regarding protecting against rising seas, Stein recommended verifying predictions by observing levels over the next five years. Of course, an earlier discussion was about which predictions the city should use. What was presented were the predictions from the California Coastal Conservancy-adopted climate-change policy.

The following was taken from Stein's report: By about 2020, king tides could be 3 inches higher than today, on track for a 55-inch rise in sea level by 2100.
He also suggested setting new harbor-wide standards for seawall elevation to 10 feet and establishing new requirements for the finish floor elevations from 1 to 4 feet.
The report considered tide gates at the harbor jetty and whether they could reduce overall harbor protection costs. Another concern was sea-level-rise protection measures for the Balboa Peninsula.
So what will start to happen when five years go by and the sea level has risen by 3 inches? I would hope you would see the city purchase a consultant's report to see if a tide gate will work. At this point, a tide gate would still be more than 10 years out before completion.
The city's standard for seawall height will be increased to 10 feet. The Balboa Peninsula will have to consider sand berms up to 5 feet high and hope that its floor elevation is above 11 feet.
The second presentation looked at the Balboa Island Seawalls Replacement Project. To see the best explanation of what is being considered, go to the city's website, newportbeachca.gov/seawalls. Send comments to seawalls@newportbeachca.gov. Also, while walking around the island, look for the story boards located at different light poles on the boardwalk.
My observation was that the committee members are leaning toward new seawalls at 10 or 9.5 feet and moving forward with plans and engineering. The committee is reaching out for more community input.
A great deal of time was spent talking about how to pay for the seawalls and plan for the worst. I felt the consensus was to hold off on committing to build anything until there are more facts. The city will also wait and observe sea levels for the next five years to see if predictions are reached.
As 5 p.m. approached, I looked out the window and was overcome by the desire to go sailing on the Thursday night beer can races. I quietly made my way out the door with the intention of not missing the boat, no pun intended.
As I looked to the sky and reviewed all that was said in the meeting, the thought of the predicted upcoming El NiƱo made me wonder if this winter storm might move things along a little faster.
Sea ya.

LEN BOSE is an experienced boater, yacht broker and boating columnist.

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