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Advanced Underground Utility Locating

Advanced Utility Locating

Advanced Underground Utility Locating

Before beginning any residential or commercial project, identifying underground utilities and structure is critical for safety and cost reduction. State law requires a locate before any excavation begins to prevent costly damage to underground utilities in the area.  However, public locates are very limited in scope, leaving private utilities unmarked and some public utilities marked incorrectly.   AUUL offers complete utility identification, marking, and follow up with immediate or next day availability. We are here to make your excavation easy.

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Advanced Utility Locating

Electromagnetic utility locating (EM)

Electromagnetic utility locating (EM) is a technique used to detect and map the location of underground utilities and infrastructure using electromagnetic signals. This method is crucial for various industries such as construction, utilities management, and excavation, as it helps prevent accidental damage to buried infrastructure during digging, drilling, or construction activities.

The basic principle of electromagnetic utility locating is to use a specialized device or instrument, known as a utility locator or cable locator, to transmit an electromagnetic signal into the ground. This signal interacts with underground utilities, such as electric cables, water pipes, gas lines, and communication cables, causing them to emit a response signal. The utility locator then detects and interprets these response signals, allowing the user to determine the presence and approximate location of the buried utilities.

Advanced Underground Utility Locating
Private utility licating em and gpr -2.HEIC

The electromagnetic utility locating process involves several key steps:


  • Transmitter and Receiver Setup: The utility locator typically consists of a transmitter and a receiver. The transmitter emits a controlled electromagnetic signal into the ground through a connection to a utility line or by induction. The receiver is used to detect and interpret the response signals emitted by buried utilities

  • Signal Transmission: The transmitter sends an electromagnetic signal into the ground. This signal travels along the utility lines or through the ground itself, interacting with conductive materials and utility structure

  • Response Signal Detection: Buried utilities, due to their conductive properties, will react to the transmitted signal by emitting a response signal. This response signal is detected by the receiver.

  • Signal Interpretation: The receiver interprets the characteristics of the response signal, such as its frequency, amplitude, and phase. Based on these characteristics, the user can determine the type of utility (e.g., electric cable, water pipe) and its approximate depth and location

  • Mapping and Marking: As the user moves the receiver over the area of interest, they mark the ground with flags, paint, or other markers to indicate the location of detected utilities. This helps create a map of the buried infrastructure

  • Avoidance and Planning: The information gathered through electromagnetic utility locating is crucial for excavation or construction projects. By knowing the location of utilities, workers can avoid accidentally damaging them during digging or drilling activities, ensuring safety and preventing disruptions to utility services.

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Advanced Utility Locating

Reference Mapping

It's important to note that while electromagnetic utility locating is a valuable tool, it may have limitations in certain situations. For example, it may be less effective in areas with high levels of interference or in the presence of non-conductive materials. Moreover, the accuracy of the technique depends on factors like the quality of the equipment, the expertise of the user, and the types of utilities being located.

Overall, electromagnetic utility locating plays a vital role in preventing accidents, reducing downtime, and ensuring the integrity of underground infrastructure.

We use several devices to locate for utilities and don't rely on a single device per locate as every device has its strengths and weaknesses.

AUUL has a proven track record and method for finding and locating utilities, every locate is different and has its challenges and complexities. We have located from basic residential houses to complex military bases, piers, industrial sites, ROWs and a lot more. 

Advanced Underground Utility Locating

There are three methods when performing private utility locating: Active, Passive and Involved.

1). Active utility locating
This involves either directly connecting to a wire to transmit a signal, or using an induction clamp around a conduit to actively send a signal through a line to be detectable.   The transmitter itself can be used to indiscriminately to transmit a signal to radiate that signal off of other lines present that are metallic in nature in the ground, however this is used typically when all other methods either have issues or when locating or signal penetration on the line only travels so far such as a big cast iron water line, and there are limited connection points along the line.

2). Passive locating 
Passive locating uses the signal that is currently emitting from a line such as a active power line, telephone lines, CPS signals on gas mains and water lines, not all lines emit signal and not all lines that have signal can be detected through this method especially in congested or utility dense areas. This is typically used to check an area for utilities not detectable by active locating or when no other connection points exist on a line.

3). Involved Utility locating- NON metal or poor signal 
This method is used as an addition to other methods to locate utilities that are non conductive in nature such as sewer lines, storm lines, fiber lines in a conduit with no tracer, empty conduits, empty water lines, mystery pipes, and a variety of other uses.

AUUL will use a sonde transmitter, locatable fish tape or locatable rodders to shove a locatable cable into a pipe to then transmit a signal through the line to then find the non metallic lines location above ground. This method is very effective when used to locate  end of buried conduits, conduit paths, difficult to locate water lines or in areas where GPR visibility is poor or unusable. 

Advanced Underground Utility Locating
Advanced Underground Utility Locating

If We Can't Find It, It Can't Be Found. Contact an office near you to get a free quote. 

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