Now, the pond located in the Storybrooke Heritage Park has become an important location, so I believe it should get it's own page. There are a couple of reasons why:
1. It is a portal to the Underworld - As the Underworld is a new/unique land, it seems only natural its portal gets a page. We have pages for Magic Doors, Magic Wardrobe, and Lake Nostos.
2. It has been used multiple times - As is has been used multiple times, it is not just a one time thing. The Underworld portal has been used three times (The Price, Broken Heart, Swan Song). It will most likely be used a fourth time to get back to Storybrooke.
If this has already been discussed recently, I'm sorry.