Usage of any external copyrighted source of information, in order to add information to the Waze database or maps, is not allowed. External copyright information includes any online or printed map information that is not provided by Waze through the Waze Map Editor interface.
With the recent acquisition of Waze by Google, Inc., changes have been made to the Waze Map Editor to include updated aerial and street view images from Google. These are considered internal sources and completely acceptable to be used in creating map information for Waze. Google's terms of use restricts use of their map information to specific conditions and Waze has the proper licensing to use what you see inside the Waze Map Editor, but nothing else.
Using any source of external copyright information puts the Waze maps under danger of being forced to revert all changes done to the map in your area / country.
If any user were to do such a thing, it would taint all the work that person did on the maps and Waze would need to reverse out all those edits. There could also be other adverse effects. Waze has already had to remove all the maps for Chile, and other South American countries because the source of the map data was not properly licensed (not the result of any Waze action).
Users may negotiate with officials in their country for access to aerial images that Waze can use. The user must be careful not to give the impression that they are acting on behalf of Waze. But as an interested citizen any user can speak with local authority, in a local language, to explain the benefits to their country in making aerial images freely available as a public good.
Note that external copyright information does not include any source of information that is provided by Waze through the internal tools of the online editor or application. Also any information developed independently by a user being physically present at a site is acceptable to add to the map as long as it is provided without copyright.