Log into iCloud.com.
Click on your name in the top right corner.
Click the Advanced Tab.
You will be presented with an option to "Reset Photo Stream" along with a warning that "This will not remove Photos from your devices" (you need to disable Photo Stream on the device to do this).
However, it does give you some control over deleting photos you do not wish to be on Apple's servers.
Click on your name in the top right corner.
Click the Advanced Tab.
You will be presented with an option to "Reset Photo Stream" along with a warning that "This will not remove Photos from your devices" (you need to disable Photo Stream on the device to do this).
However, it does give you some control over deleting photos you do not wish to be on Apple's servers.