HOW TO ENABLE NEW DLC SURFACE FEATURES INTO YOUR EXISTING SAVE IF YOU OWN THE DLC:
DISCLAIMER: You are doing this at your own risk so make a back up! There is a possibility that you may have a base/ landed vessel where these will spawn in - you have been warned!
1. Generate a new save
2. Go into the Kerbal Space Program>saves folder
3. Open the persistant.sfs file in notepad
4. Locate the ROCSeed # and copy it (see image)
5. Paste into the old save at the same line
6. Save it and give it a go!
Rocketology's post in Enabling Surface features without new savegame? was marked as the answer