Under-Pavement Cavity Detection

Finding under-pavement anomalies before a disastrous collapse is at the core of the GEO SEARCH mission to Protect Lives and Livelihoods.


Anomalies Uncovered


Miles Surveyed

All surveys completed at traffic speeds


While some parts of the world are susceptible to sinkhole formation due to soil conditions, seismic activity, or underlying geology, sinkholes have become a common problem everywhere there is aging urban infrastructure. Throughout the world, fresh water, storm water and sewage pipes under our cities are getting older.  When the age of these water conveyance pipes reach the 50-to-60-year mark, they invariably begin to leak with greater frequency, which can gradually or suddenly erode the soil supporting roadways and sidewalks, resulting in sinkholes which collapse roadways and put lives in danger.

In Japan and other markets, GEO SEARCH performs regular proactive investigations for under-pavement anomalies throughout cities, on high-speed highways, and even on airport runways and taxiways.  

Similar to periodic Pavement Conditions Index (PCI) surveys which measure the quality of roadway surfaces in the United States, periodic GEO SEARCH anomaly detection surveys find dangerous hazards which are below the pavement.

As an ancillary benefit, if a cavity is caused by a leaking water pipe the GEO SEARCH survey also allows water agencies to repair their infrastructure, saving our precious water resources.

Periodic GPR surveys for under-pavement hazards demonstrably enhance general public safety and Protect Lives and Livelihoods.

In addition, it is recommended that GEO SEARCH anomaly surveys be conducted prior to any and all road repaving or resurfacing projects.  This helps guarantee that the entire roadway, including below the pavement surface, is sound and stable and free from cavitations and potential sinkholes before repaving.

GEO SEARCH under-pavement anomaly surveys are conducted without traffic control, and at normal traffic speeds up to 60 mph.

The Process

Step One – the Primary Survey

The requesting city, county or road agency assigns a route, and the GEO SEARCH team will drive the route while scanning with proprietary GPR equipment to gather all data with accuracy.  Over the following hours and days, the GEO SEARCH analysis team (supported by brilliant AI algorithm developers, with an unmatched three-decades-worth of proprietary GPR data) will provide anomaly location reports.  Anomalies are then prioritized according to estimated level of hazard and risk.

Step Two – the Secondary Survey

If there are anomaly locations of particular interest, GEO SEARCH will support the city or road agency in a Secondary Survey.  This survey includes the insertion of a video-scope and 3-D scanning laser or LiDAR to visually assess and then measure the volume and configuration of any cavity discovered, and possibly determine the source of the cavitation (sometimes a leaking water pipe is visible).