[Leftcoast]

Concrete ships and barges were used extensively during WWII (and some in WWI).  The basic design was slow and fuel inefficient but given the shortage of steel and the need to carry supplies to the Pacific and European fronts, concrete was a viable alternative.  They made just one or two round trips but that was enough. 

The ships were slow and much too inefficient for peace time work and many were purposefully sunk to form breakwaters and reefs after the wars.  This world war I era derelict is still in place south of Santa Cruz at Seacliff beach in Aptos.



(Picture courtesy of wikimedia)

[Leftcoast]

Concrete ships and barges were used extensively during WWII (and some in WWI).  The basic design was slow and fuel inefficient but given the shortage of steel and the need to carry supplies to the Pacific and European fronts, concrete was a viable alternative.  They made just one or two round trips but that was enough. 

The ships were slow and much too inefficient for peace time work and many were purposefully sunk to form breakwaters and reefs after the wars.  This world war I era derelict is still in place south of Santa Cruz at Seacliff beach in Aptos.



(Picture courtesy of wikimedia)