ULTIMATE SHREDDER
PACIFICA AUTHOR: THE MARINE AND THE FLOWER CHILD

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"If you live on the Coast, you should expect to have higher costs." This does not consider the whole equation.

(1) Sea walls destroy beaches.
(2) Sea walls destroy or change surf breaks.
(3) Sea walls, like any other structure, are subject to erosion.
(4) Asking those who live inland to pay for someone's "choice" (against best advice) to build and live on an eroding edge is unfair and unsustainable. People will pay for schools. Houses that will fall into the sea? Not so much.

The forces at work are so great that we cannot see them in the myriad little changes all around us. Managed retreat coupled with conservation is our best hope to live with this global change.

Sharon, the link you gave says that a "Seawall is a soil retaining wall along a shoreline with the purpose of defending the shoreline against wave attack." So a retaining wall is a sea wall if it's on the shoreline.

If you look up the definition of a sea wall (or seawall), you find very general descriptions such as "a wall or embankment erected to prevent the sea from encroaching on or eroding an area of land." https://www.google.com/search?rlz=1C5CHFA_enUS770US770&q=Dictionary#dobs=sea%20wall

"Seawalls are vertical or near vertical shore-parallel structures designed to prevent upland erosion and storm surge flooding. The term 'sea wall' is commonly used to describe a variety of shoreline armoring structures including revetments." http://www.beachapedia.org/Seawalls

The Wikipedia entry for sea wall says: "[S]ea walls need to be maintained (and eventually replaced) to maintain their effectiveness" and that "various environmental problems and issues may arise from the construction of a sea wall, including disrupting sediment movement and transport patterns. Combined with a high construction cost, this has led to an increasing use of other soft engineering coastal management options such as beach replenishment." https://en.wikipedia.org/wiki/Seawall

Peter, there is a very real difference between the two. Here is one explanation. I am sure there are more out there: http://www.universalengineering.net/services/structural-design-engineers/retaining-wall-and-seawall/. Regarding maintenance costs, if you live on the Coast, you should expect to have higher costs and they should be budgeted and saved for just as an HOA has to do.

Sharon, I'm aware that the structure on Beach Boulevard north of the pier is a retaining wall and not the technical definition of a sea wall. But I'm not talking about that. I'm talking about the rock revetment along the coast at Shoreview and Esplanade. Technically, those aren't sea walls either, but then neither is the India example cited before that requires boulders to be added every year. People use the words "sea wall" to refer generically to any structure that's placed on the beach to protect whatever is behind it, but as soon as you point to a specific structure and call it a sea wall, someone says it's not a sea wall, it's something else. It reminds me of the line in the football movie where the player says to management, "Every time I say it's a game, you say it's a business, and every time I say it's a business, you say it's a game."

Of course all public works require maintenance, but a sea wall is a very particular type of public work that's intended to protect buildings and infrastructure in a limited area and that has very high initial and potentially high ongoing maintenance costs. I'm not opposed to sea walls. But the relative costs and effectiveness of different means of protecting buildings and infrastructure on the coast need to be considered. We also need to consider who pays for them and how they are paid for. That's why I urge everyone to read the Final Draft Adaptation Plan at http://www.cityofpacifica.org/civicax/filebank/blobdload.aspx?t=71473.05&BlobID=14414

Development opportunities and full employment for the coastal armoring construction industry. Bring on the sea-level rise and higher-energy storms for the sake of short-term jobs and quarterly corporate profits. Pacifica is a city, and cities rule. It don't need no beach-lovin' enviromeddlers gettin' in the way of progress.

Peter, if you are referring to the structure at Sharp Park, it is not a sea wall, it's a retaining wall and, yes, public works do require regular maintenance. Using that logic, we should not build roads, sewers, or anything else because they all require maintenance.

In Pacifica, we have a proven record that sea walls fail to prevent cliff retreat and that they require ongoing maintenance and costs. A unique and unusual example of an enormous sea wall in India is not particularly relevant to Pacifica, where we already have experience with sea walls. Even the India example requires that every year "the government adds more boulders to keep it strong." Please read the Final Draft Adaptation Plan at http://www.cityofpacifica.org/civicax/filebank/blobdload.aspx?t=71473.05&BlobID=14414

Everyone knows sea walls also cause loss of surfing waves. So, in addition to losing the beach, Pacifica would lose its quality surf. People come from all over the world to surf here. Even worse, a sea wall would cause loss of wetlands and beach, which are food sources for many birds, including the iconic oystercatcher.

http://www.beachapedia.org/Seawalls

https://global.nature.org/content/using-nature-to-build-a-stronger-coast

Did you read the articles? Because they never say sea walls aren't practical. Sea walls are an important part of coastal management, such as the one along Beach Boulevard. But other places, such as Linda Mar Beach, would lose what we love about them, such as actual beach, if we put a huge sea wall there.

Have to disagree that sea walls are impractical. Sea walls have been constructed for at least a thousand years and have a proven record of having survived many hundreds of years.

For example:

On December 26, 2004, towering waves of the 2004 Indian Ocean earthquake tsunami crashed against India's southeastern coastline, killing thousands. However, the former French colonial enclave of Pondicherry escaped unscathed. This was primarily due to French engineers who had constructed (and maintained) a massive stone sea wall during the time when the city was a French colony. This 300-year-old sea wall effectively kept Pondicherry's historic center dry even though tsunami waves drove water 24 ft (7.3 m) above the normal high-tide mark.

The barrier was initially completed in 1735 and over the years, the French continued to fortify the wall, piling huge boulders along its 1.25 mi (2 km) coastline to stop erosion from the waves pounding the harbor. At its highest, the barrier running along the water's edge reaches about 27 ft (8.2 m) above sea level. The boulders, some weighing up to a ton, are weathered black and brown. The sea wall is inspected every year and whenever gaps appear or the stones sink into the sand, the government adds more boulders to keep it strong.

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