Utility Surveys

Utility and GPR Surveys undertaken to PAS128 Standards
Ground Penetrating Radar

We provide all aspects of underground utility surveying.

Detecting underground services using Radiodetection equipment and Mala GPR
Tracing electric and communication cables.
Drainage tracing with sonde.
All of the above with a Topographical Survey.

Our Utility Surveyors are trained on specialised courses approved by TSA (The Survey Association)

We can use Utility Surveying in conjunction with Topographical Surveys to produce drawings with accurate location of services. Depending on the purpose of the job, different levels of accuracy can be achieved, in position and depth.

We use PAS 128 compliant utility surveys. There are 4 survey types and 10 quality levels:

Survey Type (Establish with client prior to survey)		Quality Level	Post-processing	Location Accuracy		Supporting Data
Survey Type (Establish with client prior to survey)		Quality Level	Post-processing	Horizontal ¹⁾	Vertical ²⁾	Supporting Data
D	Desktop utility records search	QL-D	-	Undefined	Undefined	-
C	Site reconnaissance	QL-C	-	Undefined	Undefined	A segment of utility whose location is demonstrated by visual reference to street furniture, topographical features or evidence of previous street works (reinstatement scar).
B	Detection ³⁾	QL-B4	No	Undefined	Undefined	A utility segment which is suspected to exist but has not been detected and is therefore shown as an assumed route.
		QL-B3	No	±500 mm	Undefined (No reliable depth measurement possible)	Horizontal location only of the utility detected by one of the geophysical techniques used.
		QL-B3P	Yes	±500 mm	Undefined (No reliable depth measurement possible)
		QL-B2	No	±250 mm or ±40% of detected depth, whichever is greater	±40% of detected depth	Horizontal and vertical location of the utility detected by one of the geophysical techniques used. ⁴⁾
		QL-B2P	Yes	±250 mm or ±40% of detected depth, whichever is greater	±40% of detected depth
		QL-B1	No	±150 mm or ±15% of detected depth, whichever is greater	±15% of detected depth	Horizontal and vertical location of the utility detected by multiple ⁵⁾ geophysical techniques used.
		QL-B1P	Yes	±150 mm or ±15% of detected depth, whichever is greater	±15% of detected depth
A	Verification	QL-A	-	±50 mm	±25 mm	Horizontal and vertical location of the top and/or bottom of the utility. The information gathered once the utility has been exposed shall include as a minimum, depth from top of utility to a reference point installed on the surface level.
¹⁾ Horizontal location is to the centreline of the utility. ²⁾ Vertical location is to the top of the utility ³⁾ For detection, it is a requirement that a minimum of GPR and EML techniques are used. ⁴⁾ Electronic depth readings using EML equipment are not normally sufficient to achieve a QL-B2 or higher. ⁵⁾ Some utilities can only be detected by one of the existing detection techniques. As a consequence, such utilities cannot be classified as a QL-B1.