The Concrete Ships of US Navy

While the world was enjoying some major changes in the world of shipbuilding, where ships had become an integral part of trade, commerce and national security, efforts were always made to keep upgrading them. As one of such ideas, concrete ships were introduced in US navy during the early 1900s.

Before beginning about fate of US navy concrete ships, let’s consider what these ships really are. As the name suggests, these ships were made out of concrete or cement (reinforced cement, precisely) and steel. The use of other shipbuilding material used traditionally was limited in these ships. The first time a concrete ship was built was in 1917 in Norway. These ships were heavier than traditionally built ships and needed more supporting material .i.e. a stronger hull. Ideally the weight of the ships and reduced space were considered two major concerns with these ships. But was it all?

The association of US navy with concrete ships goes back to World War I. During WWI, America faced an unprecedented steel scarcity. Considering it was war time, this could turn detrimental for the war. Hence, President Woodrow Wilson, following success of concrete ships and boats in other parts of world ordered a small fleet of 24 concrete ships to be built. The success of these boats can be comprehended from the fact that out of 24 ordered ships, only half were complete before or during the war time. Sadly of those twelve, none could serve a major purpose for the US navy.

The likes of S.S. Moffitt, S.S. Cuyamaca and S.S. Latham have been converted into oil barges while S.S. San Pasqual has been turned into a hotel and S.S. Palo Alto is being used as a dance club and restaurant. Most of the ships of this fleet either sank or were used as breakwater. Some were grounded. Only S.S. Peralta of the original US navy concrete ships fleet is still afloat today. Turned to as a desperate measure, concrete ships had turned out to be more of a liability than an asset. They were costly, bulky, heavy, and needed much longer to be built. They ‘shattered’ in the ocean and caused more damage to the US navy itself rather than the opponents. It seemed the whole concrete ships idea was a bad one.

However, during WWII, going through the same problem of steel scarcity, again a fleet of 24 concrete ships was brought in use from the McCloskey and Company. This time, the concrete and maritime industries were both much more evolved to handle the wartime responsibility. All the 24 ships were built on time and quickly launched. They were lighter, more combative and lesser labor intensive in nature. Most of the ships from this fleet are still afloat although not necessarily as US navy concrete ships. Many have been turned into floating breakwater while some were sunk as breakwater; some are used for ferry purposes while others were sold off to private owners or purpose of scrap. This fleet marked the end of concrete ships in maritime history.

Some are convinced it was for good. Despite of breakthrough inventions and modifications in the whole technology of use of concrete in maritime industry, there is no denying the fact that these ships were made of cement, and were always more vulnerable as opposed to being considered more sturdy.  It seems cement ships were a bad decision made twice in maritime history of America.

However, considering the purposes they served in both the wars, it might be a little disparaging to say they were completely useless. They were used as block ships on several occasions which undoubtedly provided US navy some leverage. Yet, it can’t be denied cement ships lacked the combative skills that were needed for wartime.

Concrete ships can’t be discarded as a completely bad idea. If we had to put it, we’d say they were a mildly crude idea that needed a lot of refining. Even today, cement ships might have a lot in store for the maritime industry but it would take a lot of alteration and perhaps a breakthrough in marine technology before they can be considered as ‘the next big thing’.

References: Concreteships , sandiegohistory

Image Credits: Concreteships , biminiadventure

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  1. Brendan Nolan says

    That this might be a crude idea that needs some refining I found to be an interesting observation. If the rebar were replaced with a modern non magnetic alternative one would have hull with a zero magnetic signature that would also shield the interior would one not. The question for materials folks is what would you use to replace the rebar?
    Perhaps not the prettiest hull on the oggin but you could probably set up to churn them out. Just set the mould and pour. Minesweepers by the dozen in case of conflict. I wonder how the manufacturing costs might compare with contemporary solutions?

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