We've seen Haven take off as a nouveau girls' name; Harbor could follow in its wake. 

Harbor

Among a small shower of rain-related names, this pure version can have a cool, refreshing image. 
 Richard Pryor named his now-grown daughter Rain, and Rain is also one of the nature-named Phoenix family siblings. More recently, 24 actress Marisol Nichols named her daughter Rain India.
 Rain also makes a nice nature middle name--Brooke Burke called her daughter Heaven Rain.
 If you want to embellish this simply spelling (and alter the meaning), you might also consider Raine, Raina, Rainn, Rayne, Reine or Reign, the middle name of Willow Smith. Or you could take the Holly Madison route all the way to Rainbow.

Rain

Rivage

River shares the tranquil feeling of all the water names, and seems to have pretty much escaped its past strong association with River Phoenix and his unfortunate fate. Actor Joaquin Phoenix named his son with actress Rooney Mara after his brother River.

River's popularity is rising for boy genders, but it's still predominantly given to baby boys. Last year nearly 3500 boys were named River vs. about 1900 baby girls.

Keri Russell and the Taylor Hansons both have sons named River, Natasha Henstridge used it as the middle name of her boy Tristan, and Jason Schwartzman pluralized it for daughter Marlowe Rivers.

River

Lakins's list "Water Words" of 4 great name ideas: Harbor - River!

Water Words

Names having anything to do with water in any way.  To include bodies of water in any language, precipitation, land surrounding water etc.

Water Words

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