Related Clues:

• Summer camp location
• Of sedate character
• Tame
• Caspian Sea, really
• Storm preceder, supposedly
• Prim and reserved
• Place for a dip
• Serenity found in 17-, 26-, 42- and 54-Across
• Ontario, for one
• Erie or Superior
• Body of water
• Unworried
• Completely calm
• Placid, for one
• See 20 Across