220.0 R – — 2025 California Plumbing Code

Rainwater. [BSC-CG & HCD 1] Precipitation on any pub- lic or private parcel that has not entered an offsite storm drain system or channel, a flood control channel, or any other stream channel, and has not previously been put to beneficial use. Rainwater Catchment System. [BSC-CG & HCD 1] A facility designed to capture, retain, and store rainwater flow- ing off a building, parking lot, or any other manmade imper- vious surface for subsequent onsite use. Rainwater catchment system is also known as “Rainwater Harvesting System” or “Rainwater Capture System.” Rainwater Storage Tank. The central component of the rainwater catchment system. Also, known as a cistern or rain barrel.

Receiving Landscape. [BSC-CG & HCD 1] Includes features such as soil, basins, swales, mulch, and plants.

Receptor. An approved plumbing fixture or device of such material, shape, and capacity as to adequately receive the discharge from indirect waste pipes, so constructed and located as to be readily cleaned.

Reclaimed (Recycled) Water. [BSC-CG, HCD 1 & DWR] Nonpotable water that meets California State Water Resources Control Board statewide uniform criteria for dis- infected tertiary recycled water. Reclaimed (recycled) water is also known as “recycled water” or “reclaimed water”.

Recycled Water Supply System. [DWR] The building supply pipe, the water distribution pipes, and the necessary connecting pipes, fittings, control valves, backflow preven- tion devices, and all appurtenances carrying or supplying reclaimed (recycled) water in or adjacent to the building or within the premises.

Registered Design Professional. An individual who is registered or licensed by the laws of the state to perform such design work in the jurisdiction.

Regulating Equipment. Includes valves and controls used in a plumbing system that is required to be accessible or readily accessible.

Relief Vent. A vent, the primary function of which is to provide circulation of air between drainage and vent systems or to act as an auxiliary vent on a specially designed system.

Remote Outlet. Where used for sizing water piping, it is the furthest outlet dimension, measuring from the meter, either the developed length of the cold-water piping or through the water heater to the furthest outlet on the hot-water piping.

Rim. See Flood-Level Rim.

Riser. A water supply pipe that extends vertically one full story or more to convey water to branches or fixtures.

Roof Drain. A drain installed to receive water collecting on the surface of a roof and to discharge it into a leader, downspout, or conductor.

Roof Washer. A device or method for removal of sediment

and debris from a collection surface by diverting initial rainfall from entry into the cistern(s). Also, known as a first flush device.

Roughing-In. The installation of all parts of the plumbing system that can be completed prior to the installation of fixtures. This includes drainage, water supply, gas piping, vent piping, and the necessary fixture supports.