The bold blue trailer, easily recognizable to Evansville residents as the JB’s Barnyard ice cream truck, had been parked Downtown for only 20 minutes when a line began to form. While owners Briley and Jared Simpkins were visiting for an interview with Evansville Living, the young couple still served customers with the same contagious positivity that’s become a benchmark of their brand.

Cities the world over have complicated and conflicting relationships with the bodies of water on which they were built — at once drawing life...