That postcard is awesome!
A few of the fraternity houses do still have docks.
Greek Row is on Langdon Street, which is parallel to the lake, and all of the sorority houses and most of the fraternity houses are either on Langdon Street or the smaller streets branching off from it towards the lake. In that postcard, the house that has the second dock from the right is now the Delta Upsilon house . . . I wish I could name some of the others.