Appendix L: Water Everywhere
From X-Plane Wiki
When scenery is not installed for a given location, all that will be visible are airports and water. This is referred to as “water world,” and is a common problem, especially when using the eight-disc set of “Beta” installation discs.
To avoid water world, either install the scenery for the location in question, or choose to fly somewhere else. To install scenery, insert the first X-Plane installation disc (the same disc used to run the simulator) and run the installer as before. Instead of installing a new copy of the program, though, when the installer window appears, press the Add or Remove Scenery button.
If scenery for the location is in fact installed, be sure that the copy of X-Plane for which it is installed is the one being used—for instance, if a user has two copies of X-Plane installed (say, one running version 9.22 and one running 9.30 Beta), they may have different amounts of scenery installed.