Utility locating is the process of identifying and labeling underground public utility lines such as telecommunications, electricity, gas, water, and sewer lines. It involves using equipment like ground penetrating radar, electromagnetic scanners, duct rodders, and concrete scanners to detect and map the location of underground metallic and non-metallic utilities before excavation work. Accurately locating underground utilities is required by local governments to ensure worker and public safety when digging near utility infrastructure.

1. What is
Utility
Locating?

2. What is Utility Locating?
Utility locating is the process of identifying and labeling public utility mains that are
underground. These mains may include lines for telecommunication, electricity distribution,
natural gas, cable television, fiber optics, traffic lights, street lights, storm drains, water
mains, and wastewater pipes. In some locations, major oil and gas pipelines, national
defense communication lines, mass transit, rail and road tunnels also compete for space
underground.

3. Public utility systems are often run underground; some by the very nature of their function,
others for convenience or aesthetics. Before digging, local governments often require that
the underground systems' locations be denoted and approved, if it is to be in the public
right-of-way.

4. DEVICES USED IN UTILITY LOCATING

5. Ground Penetrating Radar (GPR) is a large device that looks like a grass mower
and is similarly pushed along the surface of the ground. It sends radio waves that
penetrate down into the ground as it runs laterally the surface. When these
waves come across a foreign object or change in the dielectric property of the
material, the waves bounce off to the GPR device. Any disturbance in the radio
waves appears on the screen of the GPR device. A proficient technician can
interpret the information to designate the type of underground feature. GPR is
used frequently to locate objects such as plastic, concrete, buried manholes, pull
boxes, valve assemblies, underground storage tanks, changes in soil, and other
things that cannot be located using other methods. GPR is a required tool to
detect the presence of non-metallic utilities and objects
Ground Penetrating Radar

6. Ground Penetrating Radar

7. Electromagnetic Scanning (EM) is a device that uses a transmitter and receiver to
locate metallic utility lines. The transmitter is attached directly to a utility line
through its surface feature. It will then send electrical currents down the utility
line that can be traced by the receiver. The receiver is used to identify the peaks
of the Electromagnetic fields generated from the electrical current. This is how
most underground utility lines are located. EM can only be used to locate metallic
utility lines.
Electromagnetic Scanning

8. A Split Box, another Electromagnetic scanner, is a handheld device that has a transmitter
on one end, a receiver on the other, and is connected together by a long pole. The device
is carried along the surface of the ground and detects metallic objects present under the
ground. In addition to detecting utilities, the split box is required for locating abandoned
utilities, underground storage tanks, buried manholes, and other metallic objects. Not all
utility locating companies use this device. Not using this device exposes the customer to
unnecessary risks.
Split Box

9. A Concrete Scanner is a smaller, handheld Ground Penetrating Radar (GPR) device that is
primarily used for concrete scans. The technician uses it by running it along the surface of
the concrete. Using the same technology as GPR, the concrete scanner sends high frequency
radio waves into the concrete, which bounce off of any changes in dielectric properties
within the concrete slab. It can be used to locate conduits, rebar, wire mesh, and other
objects embedded within the concrete slab.
Concrete Scanner

10. This device is a copper wire that is reinforced with fiberglass material. The reel is
approximately 150 feet long. The duct rodder is used to find non-metallic utilities
that are accessible from the ground surface. The wire within the duct rodder can
carry a current, which means that it can be hooked up to the Electromagnetic
transmitter device to send a signal down the utility through the duct rodder. After
inserting the duct rodder and connecting the transmitter to the copper wire, the
EM receiver can then be used to locate the electromagnetic fields emitted off of
the duct rodder, and in turn locate the utility.
Duct Rodder

11. Duct Rodder

12. A sonde is a small device that acts as a miniature transmitter. It is primarily used to
pinpoint blockages or to locate unusually deep utilities. When the sonde is sent down a
utility line, it sends off high powered signals as it travels through the line. These signals can
then be picked up on the surface of the ground, locating where the sonde is in the utility. A
sonde is typically sent through a utility line attached to the end of a duct rodder, however
they are also built into the head of a CCTV push camera or robotic crawler. Sondes come in
varying strengths. The deeper the utility, the stronger the sonde device needed. The signal
has to be strong enough to penetrate the soil and reach the surface of the ground in order
to be detected.
Sonde

13. Sonde

14. A rebar locator or detector is used primarily for locating rebar and reinforcement in
concrete. Using electromagnetic technology, the rebar locator produces a magnetic field
which the steel rebar responds to. A rebar locator can locate the location, direction, and
approximate depth of reinforcement in concrete.
Rebar Locator

15. A concrete thickness gauge is a non destructive technique used to measure the thickness
and integrity of concrete slabs. It can also be used to detect voids, cracks, and other
defects in concrete.
Concrete Depth Gauge

16. WE ARE ADVANCED INFRASTRUCTURE MAPPING. We have been in the Utility Locating
business for 27+ years. We provide Underground Utility Locating and Mapping services
for clients such as Engineering Companies, Surveying Companies, Construction
Companies, Municipalities, and as simple as a single homeowner in Virginia Beach, VA .
Underground Utility Services

17. Contact Us
Call us at: 757-785-5177
Mail us at:
info@aimlocatingva.com
Visit us at:
http://www.aimlocatingva.com/