Roughness Coefficient
A factor in the Kutter, Manning, and other flow formulas representing the effect of channel (or conduit) roughness upon energy losses in the flowing water.
RPM
Reinforced PlasticAny of a variety of thermoplastic and thermoset material used in sewer construction (e.g., high-density polyethylene, polypropylene, PVC, fiberglass reinforced plastics, polyester felt reinforced pipe, epoxy and polyester mortars, etc). Mortar; a form of thermoset plastic pipe.
RTR
Reinforced Thermosetting Resin; a form of thermoset plastic pipe within the GRPGlass Reinforced Plastic, a family of rehabilitation linings. Often generically known as Reinforced Plastic Mortar (RPM) and Reinforced Thermosetting Resin (RTR). family.
Runoff
That part of precipitation carried off from the area upon which it falls. Also, the rate of surface discharge of the above. That part of precipitation reaching a stream, drain or sewer. Ratoride; a form of thermoplastic PipeA long tube of clay, concrete, steel, metal, wood, etc., for conveying water, gas, oil or other materials..