A GPRS Case Study

Comprehensive Utility Mapping In Charlotte, North Carolina

Highlights

THE BOTTOM LINE

GPRS’ use of Subsurface Investigation Methodology paired with the high-speed GPR array provided the most precise subsurface utility infrastructure mapping available, found 171 lines in 55 minutes, and completed the job without disrupting traffic flow.

INDUSTRY

SERVICE

LOCATION

Charlotte, North Carolina

PM Insight

Deliverables

PROJECT APPLICATION

ASK

Download PDF

Task

Accurately map the entire subsurface utility infrastructure of 0.6 miles of three-lane, high-speed road in the city of Charlotte, North Carolina

PROBLEM

Data collection had to be done without disrupting traffic with lane closures, detours, or slow-downs
Data had to be complete and highly accurate with RTK positioning coordinates, and portable to various GIS systems
Although the high-speed array was accurate, it has limitations. To create a comprehensive map, complementary technologies & methods were required

Solution

GPRS controlled array data quality in the field: found & filtered out poor GPS coordinates on site
GPRS’ Mapping & Modeling Team employed slicing, data filters, and soil velocity calibrations to the array data to ensure precise depths and extract 171 lines for mapping
Subsurface Investigation Methodology (SIM) compensated for the limitations of the array. SIM verified utility lines & types, and corrected inaccurate data with complementary technologies'The field team provided a full surface mark-out: tracked each line to a surface feature, uploaded the verified data with RTK positioning to SW Maps & SiteMap®, to provide data portability to ArcGIS, ESRI, et al.
The field team provided a full surface mark-out: tracked each line to a surface feature, uploaded the verified data with RTK positioning to SW Maps & SiteMap®, to provide data portability to ArcGIS, ESRI, et al.

Benefits

GPRS collected all the over-road data in 55 minutes to capture 171 utility lines and other features
By supporting the high-speed array with SIM, GPRS was able to locate, identify, track, and log far more utilities than could have been found by the GPR array only
Condor Osprey software produced a comprehensive TIF file that offers data portability to ESRI, ArcGIS, CAD, QGIS, Google Earth & SW Maps, among others
GPRS’ precise depth work found two 10-foot tunnels buried 11 feet under the surface that did not appear on existing as-builts