Under the reasonable owner theory of underground water, which statement is true?

• A. Absolute right
• B. Reasonable owner theory
• C. The state owns all groundwater
• D. No rights to use water

Answer: (B)

Groundwater is treated as a private right that is not unlimited. Under the reasonable owner theory, a landowner may withdraw groundwater from his property for reasonable, beneficial use, but that right is bounded by the duty not to waste and not to unreasonably harm neighboring landowners or their wells. In other words, you have a private right to use groundwater, but you must exercise it reasonably and with regard for others’ rights. This contrasts with an absolute right (unlimited withdrawal) or with a theory that the state owns all groundwater. So the statement that under the reasonable owner theory a landowner has a reasonable, not unlimited, right to groundwater is the correct understanding.