R.I. Gen. Laws § 45-14-5: Disposition of proceeds.

All revenue derived from the assessment of charges authorized by the provisions of this chapter, or by the provisions of chapter 1734 of the Public Laws, 1946, shall be expended only for the maintenance, repair, replacement, expansion, or operation of the sewer system and sewage disposal or treatment works of the cities and towns, and/or for the payment of charges made against the cities and towns for the disposal and/or treatment of their sewage.