Long-time San Diego Reader writer Tom Arnold just wrote a cover piece entitled “Pier Review” about San Diego’s piers – and here is what he had to say about the Ocean Beach Pier — his favorite:
These days, my beloved Ocean Beach Pier has been making headlines because it is dying. The 1971-foot-long structure, with its dip in the middle and two asymmetrical arms at the end, is said to be the longest concrete pier in the world. The pier structure, according to an engineering report, “consists of prestressed and conventionally reinforced concrete components,” with the piles made of “precast and prestressed concrete elements that are grouted into holes drilled into the sedimentary rock” below the pier. It hasn’t aged well.
According to the city of San Diego’s website, “during the first 25 years of service, the structure received normal ongoing maintenance required by exposure to the harsh marine environment, where it is subjected to wind, waves and the salt?laden marine atmosphere. In 1991, the pier underwent major structural rehabilitation. Since the early 2000s, exposure to large waves and ongoing degradation has required structural repairs with increasing frequency.” And from January 6 until July 1, the pier was closed to the public “after being damaged by storms and high surf in January, which has happened several times in recent years. The city’s consultant assessed the full extent of the damage after the storm season passed and determined that while the pier had minor damage to its buildings, railing and pump station, it sustained less structural damage this storm season than in past storm seasons. That means that while the pier continues to degrade over time, it is currently structurally safe to support public use. Before the pier can reopen, city staff need to address the minor damage to the pier’s buildings, railings and pump station. All of the necessary repair work is expected to be completed in July.”
But despite the pier’s relatively minor damage and recent reopening, its days are numbered. A study released in December 2018 found a number of structural problems and determined the pier is near the end of its life. The study, by consultancy Moffatt & Nichol, noted “significant deterioration of the primary structural elements,” including cracks in one out of every four pilings and “significant corrosion in the majority of the pile caps and the soffit of the deck panels.” The study found engineering and construction mistakes, including the assumption that “the maximum wave crest elevation” would be just three feet below the deck, which has not proven to be the case. In other words, the entire pier was built too low, which is why it has been continually battered by destructive waves — a problem that will only worsen as sea levels rise.
According to the report, much of the existing damage to the pier “appears to be associated with the cast-in-place portion of the cap. It was reported that during the curing of the cast-in-place joint it was very difficult to hold the two precast portions of the cap rigid. Relative movement of the two precast portions during the curing of the joint may well have caused cracking that contributed to the permeability of the joint. This would have allowed more rapid penetration of chloride ions, water, and oxygen to the reinforcement, accelerating the corrosion process.”
The 364-page report concluded that the best course of action would be for the pier to be torn down and replaced (at a cost of $40 million to $60 million) rather than repaired ($8 million) or rehabilitated ($30 million to $50 million). The city is now slowly working its way through the process.
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