A couple of years ago at a Harbor Commission meeting, the topic of replacing some of our harbor's 18 miles of seawalls an estimated cost of $500 million was discussed.
Of course, the cost is what first grabbed my attention, along with how the commissioners responded to the topic. It was then that Marshall Duffield introduced me to the concept of a tidal gate and started to explain how these gates can protect the whole harbor.
Jump forward two years, and the idea of replacing seawalls was still being discussed at this month's Tidelands Management Committee meeting. Attending the meeting as concerned harbor users were Duffield and someone I was introduced to at the beginning of the year, Jim Dastur.
At this year's Tidelands meetings, Dastur has always presented himself as a very peaceful man who does not get emotional while expressing his views on why he feels that the city should proceed with a study on the feasibility of a floodgate at the entrance to our harbor. During this month's meeting, the committee gave Dastur the time to review his reasons on why a study is needed regarding tidal gates. Sitting next to me was Win Fuller, a local resident and active harbor user, who looked at me and said, "This guy is making the most sense."
After the meeting, Duffield walked up to Dastur, introduced himself, shook his hand and gave him a warm pat on the back. This is when the idea of talking to Dastur first came to mind, and I proceeded to ask him for an interview, which he graciously accepted.
Dastur has lived on Balboa Island for 22 years. He was educated as a civil structural engineer and worked in marine construction. He has worked on most of the big commercial docks in the ports of Long Beach and Los Angeles. He also has taken part in the retrofitting of all the major bridges in the Bay Area. For three years, he was the head director of the American Society of Civil Engineers' Construction Institute. Dastur was also contracted by India to consult on the building of a nuclear power plant with a seawater intake system — not to mention the fact that he was also the interim CEO of the company that worked on the replacement of the New Orleans levees.
Dastur is the type of person who prefers not to talk about himself, but when he said, "I am talking from a lot of experience," I wanted him on our team. While discussing the replacement of our harbor's seawall, he said, "Rising the walls will not do the job. Unless the walls go way deep, way deep, all you are doing is preventing the water from coming over the top."
To proceed on this topic, you have to ask yourself which government agency, from around the world, is providing you with enough facts that our sea level is rising and by how much. It was reported at the Tidelands meeting that by 2050, the projected sea level will rise by 1.38 feet, with a 1% chance that tide height will be 9.09 feet and a 10% chance that it will be at 8.79 feet. Right now, our mean sea level is at 2.65 feet, and by 2050, it is projected to be 4.03.
Now look at today's water table on Balboa Island at plus three or plus four and consider that the water table could raise to plus six or seven within the next 30 years. This means that if we only replace our seawalls, the water won't come from over the top of the seawall but from under the ground.
It has been said, by one of our council members, that no politician will recommend to pay for a $200,000 study for a tidal gate. Dastur explained to me that "a study needs to be done to see if it is feasible. Before you throw out the concept, we should look at the study. The gate has to be looked at when you look at the harbor holistically and not confuse the gate with the condition of the seawalls."
A couple of things you should understand about tidal gates. Yes, they are very expensive. It would take about 10 years to build the gates. The gates are not up all the time. They would be on the bottom of the harbor channel and would only be raised about four and five times a year for about four hours at a time. In the future, they could be used as many as 15 times a year.
There is much more information on this topic to share with you, and I will post it on my blog. For what it's worth, I am in favor of urging our City Council members to have further discussion regarding tidal gates and would request that they consider moving forward with a study.
LEN BOSE is an experienced boater, yacht broker and boating columnist.