Sec. 3. Notwithstanding IC 8-1-2-103(a), a utility may adjust an unusually large bill if the excess usage reflected in the bill is caused by physical damage to any facility or equipment supplying water to the premises and the damage:
(1) is not visible or detectable on the customer's premises except upon excavation or some other disturbance of the property; and
(2) is not the result of an act of the customer, or of any agent or contractor hired by the customer.