Scale Dependent Data Help

Why do features appear and then go away when I zoom in or out?

The interactive mapping technology that is used in this site has the capability of showing multiple resolutions of data layers for the same theme. In other words when you are viewing the entire U.S. it is not appropriate to show highly detailed information. Also, we may only have very coarse data of any given layer. In that case it would not be appropriate to show a coarse data set when you are looking at small detail.

More to come.