R.I. Gen. Laws § 23-19.3.1-1: Purpose.

The purpose of this chapter is: (1) to prevent the backflow of untreated sewage into residences which can cause damage to property, render the residence temporarily unfit for habitation and increase the risks to public health; and (2) to require new residential construction or substantially altered sewer connections to have check valves installed at the time of construction or alteration as a reasonable means of protecting public health and safety.