Definition for Underground Utility Terms D-F

Data Logger: A device that records and stores data, such as pressure, flow rates, or temperature, for analysis and troubleshooting of utility systems. Data Logger

Dead End Main: An underground utility pipe or line that does not connect to other pipes or conduits, typically requiring special consideration in terms of pressure management and maintenance. Dead End Main

Dechlorination: The process of removing or neutralizing chlorine or chloramines from underground water systems, ensuring compliance with water quality standards and minimizing environmental impacts. Dechlorinination

Dewatering System: Equipment or methods used to remove or control groundwater from underground excavations or construction sites, allowing for safe and dry working conditions. Dewatering System

Dewatering: The removal of groundwater or excess water from an excavation to facilitate construction or utility installation. Dewatering

Dielectric Fittings: Insulated fittings or connectors used in underground utility systems to prevent electrical conductivity or galvanic corrosion between different materials or pipe sections. Dielectric Fittings

Dielectric Union: A fitting used to join dissimilar metals in a pipeline, preventing galvanic corrosion. Dielectric Union

Direct Burial Cable: An underground cable designed for installation without the need for additional conduit or protective piping. Direct Burial Cable

Directional Boring: A trenchless method of installing underground utilities by drilling a bore path and pulling or pushing pipes or conduits into place, minimizing disruption and surface disturbance. Directional Boring

Directional Control Valve: A valve used in underground hydraulic systems to regulate the flow direction of fluids, allowing for precise control and efficient operation. Directional Control Valve

Directional Drilling: A trenchless method of installing underground utilities by drilling a pilot bore and then enlarging it while simultaneously inserting the utility pipe, minimizing surface disruption. Directional Drilling

Discharge Control: Measures and devices employed in underground stormwater management systems to regulate and control the rate of water discharge, preventing flooding or erosion. Discharge Control

Discharge Permit: A permit issued by environmental regulatory agencies that allows the controlled release of treated wastewater or stormwater from underground utility systems into the environment. Discharge Permit

Discharge Pipe: The pipe or conduit through which fluids or wastewater are discharged from a system or structure. Discharge Pipe

Discharge Point: The location or outlet where fluids or wastewater are released from a utility system into a designated area or environment. Discharge Point

Disinfection: The process of killing or inactivating microorganisms in water or wastewater systems to ensure public health and safety. Disinfection

Dissolved Oxygen Sensor: A sensor or probe installed in underground wastewater systems or water treatment plants to measure the concentration of dissolved oxygen, indicating water quality and treatment efficiency. Dissolved Oxygen Sensor

Distribution Box: A junction box used for distributing electrical or telecommunications cables to multiple directions. Distribution Box

Distribution Panel: An electrical panel that distributes power from a main source to multiple circuits or loads in a building or facility. Distribution Panel

Drill Rod: In the context of underground utilities, a drill rod is a specialized tool used in horizontal directional drilling (HDD) operations. Drill Rod

Drift Measurement: The periodic or continuous measurement of the deviation or movement of underground utility pipes or structures from their intended alignment or position, ensuring structural integrity. Drift Measurement

Drip Irrigation System: An underground irrigation system that delivers water directly to the root zone of plants or crops, minimizing water waste and promoting efficient water use. Drip Irrigation System

Drip Line: A distribution system in irrigation that delivers water slowly and directly to plant roots through small emitters or drippers. Drip Line

Duct Bank: An underground trench or conduit system housing multiple utility lines, usually for electrical or communication purposes. Duct Bank

Duct: A conduit or pipe used for housing fiber optic cables or other communication lines. Duct

Ductile Iron Pipe: A type of pipe used for underground water and wastewater systems, made from ductile cast iron and known for its strength, durability, and corrosion resistance. Ductile Iron Pipe

Earthwork: The process of moving, excavating, and compacting soil or earth materials during underground utility construction, including activities such as grading, trenching, and embankment construction. Earthwork

Easement Agreement: A legal document that grants or defines the rights and permissions for underground utility companies to access, maintain, or operate utilities within private or public property. Easement Agreement

Easement: A legal right or permission granted to access or use a portion of someone else’s property for the installation and maintenance of underground utilities. Easement

Eductors: Also known as ejectors or jet pumps, are devices that use the principle of fluid dynamics to create a vacuum or suction effect for various purposes. Eductors

Effluent: The liquid waste or wastewater discharged from a treatment process or system. Effluent

Elastomeric Joint Seal: A flexible sealing material or gasket used to provide a watertight and secure connection between underground utility pipes or components, accommodating movement and vibration. Elastomeric Joint Seal

Elastomeric Joint: A type of flexible joint used in pipelines to accommodate movement, expansion, and contraction caused by temperature variations. Elastomeric Joint

Electric Fault Indicator: A device that alerts utility personnel to the location of a fault or disruption in an underground electrical cable. Electrical Fault Indicator

Electrical Conductor: A material or wire used to carry electrical current within a utility system. Electrical Conductor

Electric Conduit: A pipe or tube used to protect and enclose electrical wiring or cables for safety and ease of installation. Electric Conduit

Electrical Ground: A connection to the Earth used to provide a safe path for electrical currents and prevent electric shock hazards. Electrical Ground

Electrical Grounding: The connection of underground electrical systems or equipment to the earth through grounding electrodes, ensuring electrical safety and protection against electrical faults.

Electrofusion Welding: A method of joining underground utility pipes made of thermoplastics, such as HDPE, by heating the surfaces and fusing them together, creating a strong and leak-proof connection. Electrofusion Welding

Electromagnetic Locator: A device used to locate and trace underground utilities by detecting the electromagnetic fields generated by the utilities. Electromagnetic Locator

Electronic Marker System: Underground markers or beacons equipped with electronic transmitters used to identify and locate buried utilities, facilitating accurate mapping and utility locating. Electronic Marker System

Elliptical Concrete Pipe: A type of reinforced concrete pipe with an elliptical cross-section, commonly used in stormwater management or culvert applications. Elliptical Concrete Pipe

Emergency Generator: A backup power generator installed in underground utility facilities or substations to provide electricity during power outages or emergencies, ensuring continuous operation. Emergency Generator

Emergency Shut-off Valve: A valve installed in underground utility systems to quickly and remotely shut off the flow of liquids or gases in emergency situations, preventing accidents or hazards. Emergency Shut-off Valve

Encasement Pipe: A protective pipe or casing installed around an existing utility line to provide additional support and prevent damage. Encasement Pipe

Endoscope: A flexible or rigid optical instrument used for visual inspection of the interior of pipes or conduits. Endoscope

Environmental Impact Assessment: A study or evaluation of the potential environmental impacts of underground utility projects, identifying and mitigating any adverse effects. Environmental Impact Assessment

Environmental Monitoring: The ongoing observation and measurement of environmental factors, such as groundwater quality or air emissions, in the vicinity of underground utility operations to ensure compliance and minimize impacts. Environmental Monitoring

Erosion Control Measures: Techniques or strategies implemented in underground utility construction to prevent soil erosion, sediment runoff, or environmental impacts, ensuring compliance with regulations and best practices. Erosion Control Measures

Excavation: The process of removing earth or materials to create a trench or hole for utility installation. Excavation

Excavator Bucket: A large attachment on an excavator used for digging trenches or excavating soil during underground utility installation or repair. Excavator Bucket

Expansion Joint: A flexible joint or connector used in underground utility piping systems to accommodate thermal expansion or contraction, reducing stress and preventing damage. Expansion Joint

Fault Current Limiter: A device installed in underground electrical systems to limit the magnitude of electrical currents during faults or short circuits, minimizing equipment damage and ensuring system reliability. Fault Current Limiter

Fault Current: The current that flows through a circuit or conductor during a fault or short-circuit condition in an underground electrical system. Fault Current

Fault Locator: Equipment used to identify faults or breaks in underground cables or utility lines. Fault Locator

Fiber Blowing: The process of installing fiber optic cables in underground ducts or conduits by using compressed air or other methods to blow the cables through the pathways. Fiber Blowing

Fiber Optic Cable: A type of cable made of thin strands of glass or plastic fibers used to transmit data signals over long distances in underground telecommunication or data networks. Fiber Optic Cable

Fiber Optic Network: An underground network infrastructure that uses fiber optic cables to transmit and distribute data, voice, or video signals over long distances with high bandwidth and speed. Fiber Optic Network

Fiber Optic Splicing: The process of joining or connecting individual fiber optic cables in underground communication networks, ensuring continuous signal transmission and minimizing signal loss. Fiber Optic Splicing

Fiberglass Reinforced Pipe (FRP): A type of underground pipe made of fiberglass and resin, offering high strength, corrosion resistance, and durability for various utility applications. Fiberglass Reinforced Pipe

Fire Hydrant: An above-ground fixture connected to a water main, providing access to water for firefighting or other purposes. Fire Hydrant

Fire Hydrant Flow Test: A procedure that measures the flow rate and pressure of water from underground fire hydrants, ensuring they meet fire suppression requirements and system integrity. Fire Hydrant Flow Test

Fish Tape: A long, flexible tool used to route and guide electrical wires or cables through conduits or underground pathways. Fish Tape

Flagger: A flagger is an individual responsible for directing traffic and ensuring the safety of workers and the public in and around underground utility work zones. Flaggers use signals, signs, and hand gestures to control the flow of traffic, guide drivers safely through the work zone, and coordinate with other personnel. Flaggers play a critical role in maintaining traffic safety during construction or maintenance activities. Flagger

Flame Arrestor: A safety device installed in underground utility systems or storage tanks to prevent the propagation of flames or explosions, protecting against fire hazards. Flame Arrestors

Flange: A mechanical connection consisting of two mating surfaces with bolts and gaskets, used to join pipes, valves, or equipment in utility systems. Flange

Flare Connection: A type of pipe joint that uses a conical fitting to connect two pipes, providing a secure and leak-proof connection. Flare Connection

Flexible Joint Sealant: A sealing material, often made of rubber or elastomeric compounds, used to provide a flexible and watertight seal at the joints of underground utility pipes. Flexible Joint Sealant

Float Switch: A device used in underground utility systems to control the operation of pumps or alarms based on liquid levels, activating or deactivating equipment as predetermined thresholds are reached. Float Switch

Floating Suction System: A device or system installed in underground storage tanks or reservoirs to collect liquids from different levels, minimizing the intake of sediments or floating debris. Floating Suction System

Flow Control Chamber: An underground chamber or structure equipped with flow control devices or gates to regulate and manage the flow of water or wastewater in underground utility systems. Flow Control Chamber

Flow Control Station: An underground facility or structure equipped with valves, meters, or controllers to monitor and regulate the flow of water, wastewater, or other fluids in underground utility systems. Flow Control Station

Flow Control Structure: An underground structure or device, such as weirs, gates, or orifices, used to regulate, divert, or control the flow of water in underground drainage or irrigation systems. Flow Control Structure

Flow Control Valve: A valve installed in underground water or gas systems to regulate and control the flow rate of fluids. Flow Control Valve

Flow Divider: A device used to distribute the flow of fluids in a pipeline among multiple branches or sections. Flow Divider

Flow Meter Calibration: The process of verifying and adjusting the accuracy of flow meters used in underground utility systems to ensure reliable measurements and data. Flowmeter Calibration

Force Main: A pressurized pipe that carries wastewater or other fluids to a treatment plant. Force Main

Force Measurement: The process of measuring the amount of force exerted on underground utility equipment, such as valves or pumps, to ensure proper operation and prevent overload or failure. Force Measurement

Fusible Link: A mechanical device designed to melt or fail at a specific temperature, activating a shut-off or safety mechanism in a utility system. Fusible Link

Fusible PVC Pipe: A type of underground pipe made of polyvinyl chloride (PVC) that can be fused or welded together using specialized equipment, creating a strong, jointless connection. Fusible PVC Pipe

Fusion Splicing: A technique used to join optical fibers in underground communication networks by melting and fusing their ends together, ensuring low-loss and high-quality signal transmission. Fusion Splicing

Fusion Welding: Fusion welding is a method used to join sections of thermoplastic pipes or conduits in underground utility installations. It involves heating the ends of the pipes and then fusing them together, creating a seamless and durable connection. Fusion welding ensures leak-free joints and enhances the overall integrity of the underground utility network. Fusion Welding