It was underwater in the alternate timeline, also known as the flash-sideways timeline. It was never explained clearly why it happened.

Underwater Technology was created in 1975.

if you go to google, type in timeline, and look for a heading with the words " technology timeline", youll find it

Society for Underwater Technology was created in 1966.

Research the technology of the 1920s (using key words "timeline of 1900s" or "timeline of technology of the 20th century"). Make a timeline with at least ten technologies (be sure to include transportation, entertainment, home life, and the work place) of that time that you think changed the way Americans lived during this period (worth 1 point for each technology you list).