Ground Penetrating Radar: Sounds Cool, But What’s It For?

What Is Ground Penetrating Radar?

Ground penetrating radar is a non-invasive imaging technique that uses radar signals to create images of what’s under the surface of the ground.

It’s easy to see why this is an inefficient method of finding out what’s underground.

The composition of the ground being examined impacts the usefulness of ground penetrating radar. Also, the strength and frequency of the transmitted signal affect how useful the technology is. Ground with higher conductivity (such as clay soils) may allow radar penetration of only a few centimeters, while a dry, uniform subsurface (of sandy soils, limestone, or concrete, for example) allows greater depth of penetration. The frequency of the radar signal also affects depth of penetration. Higher frequencies don’t penetrate as deeply as lower frequencies, but higher frequencies result in better resolution of subsurface features.

How Does Ground Penetrating Radar Work?

Pulses of microwave-band radiation are transmitted into the ground with a transmitter. A receiver picks up the reflected return signal and analyzes variations in the return signal to create an image of underground structures. With ground-penetrating radar, the boundaries between subsurface materials with different dielectric constants reflect the signal, allowing the return signal to create an image or map of what’s under the ground.

Why Should Homeowners Know About Ground Penetrating Radar?

The main reason homeowners should know about ground penetrating radar is plumbing. Ground penetrating radar allows for detection of leaks without destruction. Water leak detection is critical to the soundness of your home, because a leak under a slab foundation can cause major structural damage when it goes undetected long enough. Suppose you notice an increase in your water bill with no clear explanation for it. When this happens, a water leak detection specialist can use ground penetrating radar to examine, for example, lines running to your pool without having to dig. As you might imagine, ground penetrating radar can save a lot of unnecessary digging as well as the time and expense that would go along with it.

Ground Penetrating Radar in the Community

You may not be a homeowner, but as a taxpayer, you may be interested to know how ground penetrating radar is used in the larger community. Leaking water mains can cause major damage to roadways as well as homes and businesses. Did you know that every day in the United States, enough water is lost through leaks to fill 10,000 Olympic sized pools? With water management issues getting more attention worldwide, it’s easy to see how ground penetrating radar could be used to detect and fix leaks so that communities make more efficient use of their water resources.

Other Uses of Ground Penetrating Radar

Ground penetrating radar is used in archaeological studies, allowing more efficient and less destructive excavation.

Ground penetrating radar may only affect you directly if it’s used for water leak detection in your home or business. But the technology is also widely used in the field of archaeology  allowing less destructive exploration and helping researchers anticipate what they’ll encounter on a dig. Geologists use ground penetrating radar to study groundwater, soils, and bedrock, while engineers use it for non-destructive testing of roads and ground atop utility lines. It can be used by environmental engineers to locate landfill boundaries, by police to locate buried evidence, and by the military for detection of unexploded ordnance, mines, and even enemy tunnels.

Ground penetrating radar is truly a versatile type of technology that can be used on a large or small scale, for purposes ranging from study of ancient history to figuring out why a homeowner’s water bills have gone up.

Photo Credits: dan / freedigitalphotos.net, Arvind Balaraman / freedigitalphotos.net