All I can say is that for our pond in the area it is located the Away with Geese unit is the answer. If all you have are established "local geese" then I don't think there is much that will keep them away. After all it is "their" pond.
Aside from the nesting pair this spring (none of their eggs hatched

) I didn't have any resident geese. So, maybe the Away With Geese unit did work during the summer. It wasn't until recently that the geese started showing up. I'm assuming they are migrating geese. I'll leave the unit in the water. I'm frustrated because I know it works for other pond owners.