It is possible to reset your game on purpose, but please note that any items or currency you have accumulated in the game will also be deleted, and there is no way to retrieve them once you have done so.

If you wish to reset your game, you need to make sure that the old data is not downloaded from Google+.  Here's how:

First uninstall the game by going to your device's Settings screen, and under Apps, tapping Clear Data, and then Uninstall.

Go to Google Play to install the game.  When the game is installing, it will prompt you with a question about retrieving your data from Google Cloud.  Press CANCEL.

When you start the game, you will not be signed into Google Play. Tap the Google+ icon. You will be presented with a dialog asking which game you wish to use, local or server. Choose LOCAL, the new game you just started. At that point, Google will begin saving your new game to the cloud.