Even if the public use requirement is met, when a regulation or ordinance exceeds constitutional limitations a taking has occurred and the owner is entitled to compensation. There are three tests to determine if a taking has occurred:
1. Physical Invasion Test
Has the land been physically invaded? (e.g., a government-built dam floods the owner’s land).
2. Prevention of Harm Test
The benefit to the public from prohibiting a particular use of land is balanced against the extent of harm to the adversely affected owner. When the balance tips in the public’s favor, no taking has occurred even if the owner’s use or the value of the land is greatly impaired.