Property owners here in northern Michigan have had luck with installing stakes and stringing survey tape one foot off the ground. The geese will not go under it or over it. I was not a believer until I actually watched a goose approach the tape and become befuddled. I can tell you that they are smart enough to walk the perimeter until they find an opening. Not sure if this is practical, but your discussion topic has sparked such interest, I couldn't resist throwing my two cents worth in.
Dogs are an excellent way of handling the problem.
Many golf courses use working dogs for this purpose. I believe it takes a steady 1-2 weeks to retrain the geese. It is a liquid applied at the rate of one gallon per acre. We have tried several things to no avail. We also have a limited budget.