Definitions for Underground Utility Terms J-O

Jack and Bore: A trenchless method of installing underground utilities by using hydraulic jacks to push a pipe through the ground while simultaneously removing the soil. Learn More…

Joint Restraining Gland: A device or component used to restrain or secure the joint between underground utility pipes, preventing movement, separation, or leaks.

Joint Restraint: Devices or methods used to prevent the separation or movement of pipe joints under pressure or external forces.

Joint Sealing: The application of sealants, gaskets, or compounds to seal the joints of underground utility pipes or conduits, preventing leakage and maintaining system efficiency.

Joint: A connection point between two sections of pipe or conduit.

Jointing Compound: A material, such as lubricants, sealants, or adhesives, applied to the joints of underground utility pipes or fittings to provide a watertight seal and prevent leakage.

Jointing Sleeve: A cylindrical sleeve or coupling used to connect and join underground utility pipes or conduits, providing a secure and watertight connection.

Junction Box: An enclosure or box installed underground to house electrical connections, splices, or terminations, providing a safe and accessible location for wiring distribution.

Lateral Cleanout: An access point or opening in a sewer lateral for cleaning or clearing blockages.

Lateral Connection: The connection point between a property’s individual service line and the main underground utility line, such as water, sewer, or gas.

Leach Field: An underground area or system designed to disperse the liquid effluent from a septic tank into the surrounding soil.

Leachate Collection System: An underground network of pipes, drains, or wells used to collect and remove leachate, the liquid generated from the decomposition of waste in landfills or containment sites.

Leak Detection: The use of specialized equipment, such as acoustic sensors or gas detectors, to locate and identify leaks in underground utility systems, minimizing water loss or gas escapes.

Leakage Detection Equipment: Specialized equipment or devices used to detect and locate leaks in underground utility pipes or systems, including acoustic leak detectors, correlation devices, or leak noise loggers.

Leakage Detection System: Equipment or monitoring systems installed in underground water supply networks to detect and locate leaks or water losses, minimizing water waste and preserving resources.

Leakage Repair Clamp: A device or coupling used to repair or seal leaks in underground utility pipes or conduits, providing a temporary or permanent solution to prevent water loss or contamination.

Line Stop: A temporary pipe fitting used to stop the flow of fluids in a live pipeline for maintenance or modifications.

Linear Low-Density Polyethylene (LLDPE): A type of plastic commonly used for underground utility pipe applications due to its flexibility, durability, and resistance to chemicals.

Live-Line Tools: Specialized tools and equipment used for working on energized underground electrical systems, maintaining safety for utility workers and preventing power interruptions.

Lnestop Fitting: A temporary fitting used in live pipeline operations to create a bypass or diversion while isolating a section of the line for maintenance or repairs.

Load Bank: A device used to simulate electrical loads for testing and commissioning underground utility systems or backup generators.

Load Management System: A system installed in underground electrical networks to manage and optimize power distribution, ensuring efficient utilization and load balancing.

Load Monitoring: The continuous or periodic measurement and analysis of the load or weight supported by underground utility structures, such as vaults or tunnels, to detect any excessive stress or deformation.

Load-Break Elbow: A specialized elbow fitting used in underground electrical systems to allow disconnection or connection of cables under load.

Locator Beacon: A small device attached to underground utilities to aid in locating them using electromagnetic or radiofrequency signals.

Locator Receiver: A device used to detect and interpret signals emitted by locator beacons or tracer wires, assisting in the identification and mapping of underground utilities.

Locator Wand: A handheld device used to detect and locate buried underground utility lines or markers, emitting signals that can be picked up by receivers to pinpoint their location.

Lockout/Tagout: A safety procedure used to control hazardous energy sources during maintenance or repair work on underground utility equipment.

Magnetic Locator: A device that detects and locates underground utilities by detecting the magnetic fields around ferrous materials or structures.

Manhole Cover: A removable lid or plate used to cover and provide access to manholes in underground utility systems.

Manhole Infiltration: The entry of groundwater or surface water into a manhole structure, often indicating leaks or defects in the underground sewer system.

Manhole Rehabilitation: The process of repairing or refurbishing underground utility manholes to restore structural integrity, prevent leaks, and ensure worker safety.

Manhole Riser: A section or ring added to an existing underground manhole to raise its height, accommodating changes in grade or providing access at the appropriate elevation. Learn More…

Manhole Step: A ladder-like structure or rung system inside a manhole to provide access and facilitate descent and ascent for personnel during maintenance or inspections.

Manhole: An access point to underground utility systems, usually round or rectangular in shape, allowing personnel to enter for maintenance or repair.

Manifold System: An underground piping system that distributes fluids or gases from a central source to multiple outlets or branches, commonly used in irrigation, gas, or hydronic heating systems.

Marking Flags: Color-coded flags placed above utility lines during the locate process to indicate their presence and type.

Megger: A specialized instrument used to measure the insulation resistance of electrical cables or equipment in underground utility systems.

Meter Pit: An underground chamber housing water or gas meters, typically located near the property line or curb.

Monitoring Well: A deep well installed to measure water levels, quality, or pressure in underground aquifers or utility systems.

Multi-Utility Tunnel: An underground tunnel or passage designed to accommodate multiple utility lines or systems, allowing for shared infrastructure and efficient use of space.

Non-Destructive Testing (NDT): A variety of testing techniques, such as ultrasonic testing or radiographic inspection, used to assess the condition or integrity of underground utility components without causing damage.

Non-Destructive Testing (NDT): The use of testing methods, such as ultrasound, radiography, or magnetic particle inspection, to assess the integrity and quality of underground utility structures without causing damage.

Nonmetallic Conduit: An underground conduit or pipe made of nonmetallic materials, such as PVC (polyvinyl chloride) or HDPE (high-density polyethylene), used to protect and house electrical or communication cables.

Odor Control System: Equipment or devices installed in underground utility systems, such as sewer or wastewater treatment plants, to mitigate and control unpleasant odors generated by the system.

Odor Control: Measures or systems implemented in underground wastewater systems to mitigate or eliminate unpleasant odors, improving the air quality and environment in and around utility facilities.

Open-Cut Excavation: A traditional method of excavating underground utilities by manually digging an open trench, allowing for direct access to the pipes or cables.