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 |
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Horizontal 1) |
Vertical 2) |
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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. |
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QL-B3P |
Yes |
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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) |
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QL-B2P |
Yes |
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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. |
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QL-B1P |
Yes |
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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. |
The fees are determined by the quality of data that is needed.
The most common quality levels used are QL-B3 and QL-B2. These quality levels offer the most output for the cost of the job.
We can tailor the needs of the job and we can help you with your project in any circumstances.
For further information do not hesitate to contact us for a no commitment quote or recommendations.