Twin City Locating
Centralia, Washington
Phone: (360) 720-3333
Twin City Locating, LLC
Private Utility Locating and GPR (Ground Penetrating Radar) services
(360)720-3333
Electromagnetic (EM) Utility Locating in Southwest Washington
Electromagnetic (EM) locating is a utility locating method used to trace conductive underground utilities, such as metal pipes, tracer-wire equipped plastic lines, and energized electrical or communication cables. Twin City Locating provides professional EM locating services throughout Southwest Washington for homeowners, contractors, and property owners who need accurate utility locations before excavation or construction.
EM locating works by inducing the target line with a radio frequency from a transmitter and detecting that signal on a conductive line using a locator wand or receiver, allowing the path and approximate depth of the utility to be traced across a property. This method is commonly used for locating electrical conduits, communication lines, and plastic water services or sewer laterals equipped with tracer wire.
EM locating is especially useful when the approximate location of a utility is known and the goal is to follow its path with greater accuracy. It is often used prior to trenching, fence installation, utility repairs, or site development where avoiding utility strikes is critical.
When EM Locating Is the Right Choice
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Electromagnetic locating is commonly used in situations such as:
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• Tracing private water services with tracer wire
• Locating electrical lines feeding outbuildings or lighting
• Following known conductive utilities across a property
• Verifying utility paths before trenching or excavation
• Confirming utility locations prior to construction or repairs
Combining EM Locating With Other Methods
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In many cases, EM locating is combined with other locating techniques such as ground penetrating radar (GPR), magnetic locating, or sewer scope and sonde locating to improve accuracy and coverage. Using multiple methods helps ensure the most complete understanding of underground utilities within a work area.
Limitations of EM Locating
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While EM locating is an effective method, it does have limitations. This technique requires the utility to be conductive or equipped with tracer wire. In areas with multiple nearby utilities, signal distortion or bleed-over can occur. Non-metal utilities without tracer wire may require additional locating methods.
Before scheduling service, you may want to review typical private utility locating costs or learn more about utility locating best practices to determine the best approach for your project.