Indiana Code Title 13. Environment § 13-18-20.5-5

Sec. 5. If a person does not remit a public water system annual operation fee or an installment of the fee under IC 13-16-2 to the department not later than ninety (90) days after the date the fee is assessed or not later than sixty (60) days after the date the installment is due, the department may pursue enforcement action under IC 13-30.  However, before the department may pursue enforcement action, the department must:

notify the person by United States mail of the fees and delinquency charges due.  The notice must state that the department may pursue enforcement action for nonpayment after thirty (30) days from the date of the notice.