What happens to shipping containers that fall overboard?

While most of the shipping in the world happens via sea, what happens when the massive containers fall overboard? Where do they eventually end up?
AOL

Dozens of cargo containers fall off ship near Southern California port

Dozens of shipping containers took a tumble, falling over the side of a cargo ship and into Southern California waters on Tuesday, Sept. 9. The containers, about 75 of them, were stacked on the ...
World Socialist Web Site

Dozens of shipping containers fall at Port of Long Beach, attesting to ongoing safety issues in America’s second largest port

The Port of Long Beach, California viewed from a distance On Tuesday, September 9, at least 75 shipping containers fell off the cargo ship, the Mississippi, when unloading its cargo at the Port of ...