I can't believe none of you grew up on a farm! If you had, you'd know about taking a piece of bacon fat, tying it securely to a long piece of string, then placing it near the water.
A goose will walk up, see the bacon fat, and eat it. He can't digest it, so it will go through his digestive track and end up on the ground, but with the string still attached.
Next goose walks up, think 'Hey, free food' and will eat the same piece of fat and it will work its way through HIS digestive system too.
This happens a few times, and now you've got a bunch of upset geese... on a string.
Technically, it might not get rid of them, but it's funny to see all these geese doing a conga down by your pond.