Definitions for Underground Utility Terms P-R

Parshall Flume: A hydraulic structure used for measuring the flow rate of water in open channels or culverts in underground utility systems.

Penetrating Sealant: A sealant or compound applied to the surface of underground utility structures, such as manholes or vaults, to prevent water infiltration or leakage through cracks or joints.

Percolation Test: A test conducted to assess the infiltration rate of water into the soil for proper design and installation of septic systems or drainage fields.

Percussion Hammer: A percussion hammer may refer to a type of drilling method called percussion drilling or hammer drilling. Learn More…

Permeable Reactive Barrier: An underground barrier or zms.one created by installing reactive materials to treat or remove contaminants from groundwater as it passes through the barrier.

Phase Identification Tape: A brightly colored tape or marker installed above underground electrical cables or conduits to indicate their voltage or phase, alerting workers to potential hazards.

Pigging: The process of using a specialized device called a “pig” to clean, inspect, or test the inside of pipelines.

Piggybacking: The practice of installing new utility lines alongside existing ones by attaching or securing them to reduce excavation and installation costs.

Pinch-off Tool: A specialized tool used to temporarily stop the flow of fluids in a pipe during repairs or maintenance.

Pipe Bursting: A trenchless method of replacing underground utility pipes by breaking the existing pipe and simultaneously pulling a new pipe through the resulting void, minimizing excavation.

Pipe Dope: Pipe dope, also known as thread sealant, is a type of compound or paste used to create a tight and leak-free seal between threaded pipes and fittings. Learn More…

Pipe Inspection Camera: A specialized camera or imaging device used to visually inspect the interior of underground utility pipes or conduits, capturing real-time video or images for assessment and documentation.

Pipe Insulation: The application of insulating materials, such as foam or fiberglass, around underground utility pipes to reduce heat transfer, prevent condensation, or protect against freezing.

Pipe Jack, or Pipe Jacking: In the context of boring operations, the term “pipe jack” refers to a method used for installing pipes or casings during horizontal directional drilling (HDD) or other types of underground boring. Learn More…

Pipe Locator: A handheld device or instrument used to detect and locate underground utility pipes or cables, allowing for accurate mapping and identification during excavation or construction.

Pipe Plug: A temporary seal or closure used to block the flow of fluids in a pipeline during maintenance or repairs.

Pipe Ramming: A trenchless method of installing underground utility pipes by using a pneumatic hammer to drive the pipe through the soil, creating a bore path without the need for excavation.

Pipe Rehabilitation: The process of repairing or renewing the structural integrity of existing underground utility pipes, often through methods such as relining, slip-lining, or pipe bursting.

Pipe: A tubular structure used for conveying fluids or gases. Common types include water pipes, sewer pipes, gas pipes, and electrical conduits.

Pipeline Integrity Management: A comprehensive approach to assess, monitor, and maintain the integrity of underground pipelines, ensuring safe and reliable operation and minimizing the risk of leaks or failures.

Pipeline Pig Launcher: A launching device or assembly used to introduce a pig into an underground pipeline for cleaning, inspection, or maintenance purposes.

Pipeline Pigging: The process of using pipeline pigs, which are devices inserted into underground pipelines, to clean or inspect the interior surfaces, remove debris, or collect data for maintenance purposes.

Pipeline Rehabilitation: The process of repairing or renewing existing pipelines to extend their service life and improve performance.

Pit Bottom: The lowest point or level of an underground utility excavation or pit, often where equipment, pumps, or sumps are installed for dewatering or drainage purposes.

Pitless Adapter: A device used in water well systems to provide a watertight seal and enable the passage of pipes through the well casing without the need for a pit.

Pitot Tube: A device used to measure fluid velocity by sensing the dynamic pressure of the fluid in a pipeline.

Plenum: A space or chamber above the ceilings or below the floors of a building used for the installation of HVAC ductwork, electrical cables, or communication lines.

Plow-in Technique: A method of installing underground utilities by using a specialized plow to create a trench and simultaneously place the utility in the ground.

Plunge Pool: A deep pool or basin created at the base of a vertical or steep underground pipe or culvert to dissipate energy and prevent erosion.

Potable Water System: An underground water supply system designed to provide safe and drinkable water to residential, commercial, or industrial users, complying with quality and safety standards.

Potholing: The process of excavating small holes to expose and verify the location of underground utilities.

Power Factor Correction: Measures or equipment installed in underground electrical systems to improve power factor, reducing energy losses and optimizing power utilization.

Pre-action System: A fire suppression system installed in underground utility tunnels or facilities that combines fire detection with water-based suppression, reducing the risk of accidental discharge.

Precast Concrete Structure: Underground utility structures, such as manholes or catch basins, that are premanufactured in a controlled environment and then transported and installed on-site.

Precise Excavation: The careful and precise excavation of soil or material around underground utilities using techniques such as hand digging or vacuum excavation, minimizing the risk of damage.

Pre-commissioning: The process of testing and preparing a newly installed utility system for operation.

Pre-Construction Survey: A comprehensive survey conducted before underground utility work begins to document the existing conditions of surrounding structures, properties, and utilities.

Pressure Reducing Valve: A device used to reduce or regulate the pressure of water or gas flowing through a pipeline.

Pressure Regulator: A device installed in underground utility systems to regulate and maintain a constant pressure within a specified range, ensuring the efficient and safe operation of the system.

Pressure Regulator: A device used to maintain a constant or specific pressure within a pipeline.

Pressure Relief Valve: A safety valve installed in underground utility systems to automatically relieve excess pressure and prevent equipment damage or failure.

Pressure Sewer System: A wastewater collection system that utilizes pressurized pipes and pumps to transport sewage from individual properties to a central treatment facility or gravity sewer.

Pressure Sewer System: An underground wastewater collection system that uses pressure to transport sewage from individual properties or buildings to a centralized treatment facility or main sewer line.

Pressure Test: A procedure to assess the integrity of a pipeline by subjecting it to a controlled increase in pressure.

Pressure Transducer: A sensor or device used to measure and convert fluid pressure into an electrical signal, commonly used in underground utility systems for monitoring and control.

Pressure Transmitter: A device installed in underground utility systems to measure and transmit pressure readings, providing real-time data for monitoring and control purposes.

Pressure Vacuum Breaker: A backflow prevention device installed in underground irrigation systems to protect the potable water supply from contamination when pressure fluctuations occur.

Pressurized Irrigation System: An underground system for distributing water to agricultural fields or landscapes using pressurized pipes and emitters.

Propane Detector: A sensor or device used to detect and alert the presence of propane gas in underground utility systems.

Protective Barrier: A physical barrier, such as concrete encasement, bollards, or fencing, installed around underground utility equipment or structures to protect them from external damage or impacts.

Proving Ground: A controlled testing area or facility where underground utility equipment, materials, or techniques are evaluated or validated for performance, compliance, or functionality.

P-trap: A U-shaped pipe used in plumbing systems to prevent the backflow of sewer gases into a building.

Pull Box: An underground enclosure or junction box used for pulling and splicing electrical or communication cables.

Pulling Eye: A device or attachment used to provide a secure connection for pulling or tensioning underground utility cables or wires.

Pulling Head: A device or attachment used in underground utility installations to provide a pulling point for pulling or pushing cables or pipes through conduits or trenches.

Pump Control Panel: An electrical control panel installed in underground pump stations to monitor and control pump operations, including starting, stopping, and alarm systems.

Pump Station: An underground facility equipped with pumps, controls, and equipment to lift or move fluids, such as wastewater or stormwater, to a higher elevation or distant location.

PVC Sleeve: A PVC sleeve is a cylindrical covering or sheath made from polyvinyl chloride (PVC) material. Learn More…

Radio Detection: The use of radio frequency (RF) or electromagnetic methods to locate and trace underground utility lines or pipes, helping to prevent accidental damage during excavation.

Rainwater Harvesting: The collection and storage of rainwater for future use, often utilized in irrigation or non-potable water applications.

Reclaimed Water System: An underground infrastructure that distributes treated wastewater for non-potable uses, such as irrigation, landscaping, or industrial processes, reducing demand on freshwater sources.

Regulator Station: A facility in natural gas distribution systems that reduces the pressure of the gas before it is supplied to customers.

Regulator Station: An underground facility or structure equipped with pressure regulators, valves, and control equipment to regulate and maintain the pressure of gas flowing through distribution pipelines.

Rehabilitation: The process of repairing, upgrading, or restoring the condition and functionality of existing underground utility systems through methods such as relining, grouting, or structural reinforcement.

Reinforced Concrete Pipe (RCP): A type of pipe made from concrete and reinforced with steel bars or wire, commonly used for underground drainage and sewer systems.

Reinforced Earth: A construction technique that involves reinforcing soil or backfill material with materials such as geosynthetics, steel strips, or geogrids to create stable underground structures.

Reinforced Thermoplastic Pipe (RTP): A type of pipe made from a composite material, combining plastic and reinforcing fibers, used in various underground utility applications.

Remote Metering: A system that allows for the remote monitoring and measurement of utility consumption, such as water or energy, in underground utility systems, providing data for billing and conservation efforts.

Remote Monitoring System: A system that allows for the remote monitoring and control of underground utility infrastructure, providing real-time data and alerts for operational management.

Remote Monitoring System: An automated system that remotely collects and monitors data from sensors or devices installed in underground utility systems, providing real-time information on performance and conditions.

Remote Monitoring: Systems or technology used to monitor and control underground utility infrastructure from a centralized location.

Remote Sensing: The use of satellite imagery, aerial photography, or other remote sensing technologies to gather information about underground utility infrastructure, such as mapping, monitoring, or asset management.

Remote Shut-off: A system or device installed in underground utility systems, such as gas or water pipelines, to remotely shut off the flow in case of emergencies, leaks, or equipment malfunction.

Remote Terminal Unit (RTU): A device used to monitor and control remote equipment or processes in underground utility systems.

Remote Valve Operation: A system or mechanism that allows for the remote control and operation of underground valves, facilitating efficient flow control and maintenance operations.

Reservoir: An underground structure used for storing water or other fluids for distribution or supply purposes.

Resilient Joint: A type of joint used in underground utility pipelines that allows for movement, expansion, and contraction, accommodating ground shifts or thermal changes while maintaining a watertight seal.

Resilient Seated Gate Valve: A type of valve commonly used in water distribution systems, featuring a rubber or elastomeric seat for tight shut-off and positive sealing.

Resilient Seated Gate Valve: A type of valve used in water and sewer systems, featuring a rubber or elastomeric seat that provides a tight seal.

Restrained Joint: A type of joint in underground utility pipes or fittings that provides resistance against separation, movement, or displacement caused by external forces or internal pressure.

Right-of-Way: A designated area or strip of land where utility lines are installed, usually owned by a government agency or utility company.

Right-of-Way: The legal right granted to a utility company or entity to access and use a specific area of land for the installation and maintenance of underground utilities.

Riser Diagram: A schematic representation or drawing that illustrates the arrangement and connections of underground utility risers, such as water, gas, or electrical risers, in a building or facility.

Riser Pipe: A vertical pipe or conduit used to connect an underground utility line, such as a water supply or sprinkler system, to an above-ground fixture or equipment.

Riser: A vertical pipe or conduit used for connecting an underground utility to an above-ground fixture or equipment.

Road Plate: A large metal plate used to cover excavations temporarily, allowing traffic to pass safely over them.

Robotic Inspection: The use of specialized robotic devices or crawlers to inspect and assess the condition of underground utility pipes or structures, capturing visual data and detecting defects or abnormalities.

Rock Excavation: The process of removing or breaking through rocks during underground utility construction or installation.

Root Barrier: A physical or chemical barrier installed around underground utility lines to prevent the intrusion of tree roots.

Runoff Control Measures: Techniques or structures implemented in underground stormwater management systems to control and mitigate the volume and flow of runoff, preventing erosion and flooding.

Runout: The length of a utility line from its point of connection to the mainline to its end termination.