Subsurface Utility Engineering (SUE) is essential for managing risks related to underground utilities in infrastructure projects, helping to prevent damage to vital services and ensuring public safety. Australian standards define four quality levels of SUE, ranging from basic information (Quality Level D) to precise identification (Quality Level A). Utilizing SUE effectively minimizes project delays, design errors, and associated costs, ultimately safeguarding lives and the environment.

1. SUESUBSURFACE UTILITY ENGINEERING FOR LOCATION AND
DAMAGE PREVENTION OF UNDERGROUND UTILITIES

2. SUBSURFACE UTILITY ENGINEERING
• Understanding SUE
• Why SUE is important
• Mechanics of SUE

3. UNDERSTANDING SUE

4. UNDERSTANDING SUE
Subsurface utility engineering is an engineering practice that encompasses
the management of risks associated with many aspects of infrastructure
project management such as ……
• Underground utility relocation
• Infrastructure planning and estimation
• 3d mapping of utilities for design
• Correct Identification and location of underground utilities
• Road and Highway upgrades

5. UNDERSTANDING SUE
Australian Standards of Practice
• AS 5488-2013
• Contents:
 Definition of SUE
 Quality Levels

6. WHY SUE IS IMPORTANT

7. WHY SUE IS IMPORTANT
Prevention of damage to existing subsurface utilities
• Power
• Water
• Gas
• Sewer
• Drainage
• Communications
• CCTV
• Data
• Fuel

8. WHY SUE IS IMPORTANT
We can not rely purely on One Call ( DBYD )
systems or GIS overlays to provide accurate
location of underground utilities.

9. WHY SUE IS IMPORTANT
Risk management is the essence of SUE, by utilizing all aspects
of SUE you are minimizing costly delays and potentially saving lives.
• The Risks
 Project delays
 Damage to critical utilities
 Safety of the public
 Environmental damage
 Costly design errors
 Insurance claims
 Loss of reputation
 Time / Budget penalties

10. MECHANICS OF SUE

11. MECHANICS OF SUE
Australia recently released AS5488-2013 which defines the quality levels
of Subsurface Utility Engineering.
• Quality Level A
• Quality Level B
• Quality Level C
• Quality Level D

12. MECHANICS OF SUEQUALITY LEVEL D (QL-D) IS THE LOWEST OF THE FOUR QUALITY
LEVELS. THE ATTRIBUTE INFORMATION AND METADATA OF A
SUBSURFACE UTILITY CAN BE COMPILED FROM ANY, OR A COMBINATION
OF THE FOLLOWING :
• Existing records.
• Cursory site
inspection.
• Anecdotal
evidence.
• Utility owner.
• Indication of utility
type.
• The date of
installation.
• An indicative location
of the surface and
subsurface features.
• The date the data was
captured
• The source of
information

13. MECHANICS OF SUE

14. MECHANICS OF SUE
QUALITY LEVEL C (QL-C) IS DESCRIBED AS A SURFACE FEATURE
CORRELATION OR AN INTERPRETATION OF THE APPROXIMATE LOCATION AND
ATTRIBUTES OF A SUBSURFACE UTILITY ASSET USING A COMBINATION OF
EXISTING RECORDS AND A SITE SURVEY OF VISIBLE EVIDENCE.
• Full utilization of QL-D.
• An interpolation of the
location and direction of
the utility using surface
features as points of
reference.
• Feature codes of
surface features, pits,
access chambers,
poles, valves and
hydrants
• The location of
surface features
measured in terms of
relative spatial
positioning with a
maximum horizontal
tolerance of +-300mm

15. MECHANICS OF SUE

16. MECHANICS OF SUE
QUALITY LEVEL B (QL-B) PROVIDES RELATIVE SUBSURFACE FEATURE
LOCATION IN THREE DIMENSIONS. THE MINIMUM REQUIREMENT FOR QUALITY
LEVEL B IS RELATIVE SPATIAL POSITION.
• Full utilization of QL-D &
QL-C
• The location of surface
features measured in
terms of relative spatial
positioning with a
maximum horizontal
tolerance of +-300 mm
and maximum vertical
tolerance of +- 500mm.
• The locating method(s)
used to obtain the
attribute information

17. MECHANICS OF SUE

18. MECHANICS OF SUE
QUALITY LEVEL A (QL-A) IS THE HIGHEST QUALITY LEVEL AND CONSISTS OF
THE POSITIVE IDENTIFICATION OF THE ATTRIBUTE AND LOCATION OF A SUBSURFACE
UTILITY AT A POINT TO AN ABSOLUTE SPATIAL POSITION IN THREE DIMENSIONS. IT IS
THE ONLY QUALITY LEVEL THAT DEFINES A SUBSURFACE UTILITY IS “VALIDATED”
• Full utilization of QL-D,
QL-C, QL-B.
• Utility type, status,
material, size &
configuration.
• The location of points
surveyed on surface and
subsurface features
measured in terms of
absolute spatial
positioning with a
maximum horizontal and
vertical tolerance of +-
50mm.
• Survey control information
used to determine the
absolute spatial position of
the utility.
• The survey and locating
methods used to obtain the
attribute information.

19. MECHANICS OF SUE

20. SUESUBSURFACE UTILITY ENGINEERING FOR LOCATION AND
DAMAGE PREVENTION OF UNDERGROUND UTILITIES