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    2. QA-2 Works Undertaken By or For a Council
    3. QA-3 Development Works Approval
    4. QA-4 Survey Plan (s223) Approval
    5. QA-5 Final Sign Off (s224c) Application Requirements
    6. QA-6 As-Built Information
    7. QA-7 Bonds and Maintenance Fee
    8. QA-8 Building Consent Considerations
  5. Design Standards
    1. DS-1 General Provisions
    2. DS-2 Streetscape
    3. DS-3 Reserves
    4. DS-4 Transportation Network
    5. DS-5 Stormwater
    6. DS-6 Wastewater
    7. DS-7 Water Supply
    8. DS-8 Public Lighting
    9. DS-9 Network Utilities
    10. DS-10 Natural Hazards & Earthworks
    11. DS-11 Road Zone/Road Reserve Occupancy
    12. DS-12 Building Consent Considerations
  6. Standard Drawings
    1. SD-1 General Provisions
    2. Street design diagrams
    3. T100 Perspective Drawings
    4. T200 Streetscape
    5. T300 Reserves
    6. T400 Transport Network
    7. T500 Stormwater
    8. T600 Wastewater
    9. T700 Water Supply
    10. T800 Public Lighting
    11. AB As-Built Drawings
  7. Approved Materials
  8. Construction Standards
    1. CS-1 General
    2. CS-2 Site Clearance
    3. CS-3 Earthworks
    4. CS-4 Excavation
    5. CS-5 Excavation in Trench
    6. CS-6 Fill
    7. CS-7 Bedding & Backfill
    8. CS-8 Subsoil Drainage for Earthworks & Roads
    9. CS-9 Pipework
    10. CS-10 Pipe Fittings
    11. CS-11 Manholes & Rodding Eyes
    12. CS-12 Sumps
    13. CS-13 Trenchless Technology
    14. CS-14 Road Ripping
    15. CS-15 Road Pavement Layers
    16. CS-16 Kerb & Channel
    17. CS-17 Concrete Work
    18. CS-18 Carriageway Surfacing
    19. CS-19 Roadmarking
    20. CS-20 Berm Features
    21. CS-21 Street Structures
    22. CS-22 Road Maintenance
    23. CS-23 Grassing & Turfing
    24. CS-24 Vegetation Planting & Gardens
    25. CS-25 Reinstatement
  9. Inspection & Testing Requirements
    1. IT-1 General Provision
    2. IT-2 Streetscape
    3. IT-3 Reserves
    4. IT-4 Transportation Network
    5. IT-5 Stormwater
    6. IT-6 Wastewater
    7. IT-7 Water Supply
    8. IT-8 Public Lighting
    9. IT-9 Network Utilities
Infrastructure Development Code

CS-13.3 Directional Drilling


  1. The minimum specification for directional drilling shall be as follows:
    1. A pilot hole shall be drilled between two local pit locations.  The drilling system shall incorporate a steerable head, remotely controlled to direct the hole along the correct alignment and grade.
    2. A back reamer shall be fitted to the drill string in order to enlarge the pilot hole sufficiently to accommodate the pipe.
    3. The pilot hole shall be supported by a Bentonite slurry which also lubricates the outside of the pipe when it is drawn back through the hole.
    4. Before the pipe is drawn back through the hole, the leading end shall be sealed to prevent the entry of dirt and slurry.
    5. The pipe shall be attached to the back reamer and pulled through the enlarged hole.
    6. On completion of the pipe installation, if the annulus between the excavated hole and the pipe is not filled with slurry within the specified tolerance, it shall be filled with grout.
  2. The drilling machine shall be carefully aligned to provide a true line and grade. Should the pilot hole or installed pipeline vary more than the specified tolerance from the required line and grade, the Contractor shall open excavate part or all the affected section to rectify the line to the correct line and grade or re-pilot a new line as instructed by the Engineer.
  3. The pipe pulling equipment shall incorporate a breakaway device fitted to the leading end of the pipe to prevent the maximum pulling load being exceeded. 
  4. The Contractor shall provide evidence from an IANZ approved laboratory that the device is calibrated correctly.
  5. Where the breakaway device breaks during pipe pulling, the pulling operation shall stop immediately and the Contractor shall determine the reason for the failure and shall take the necessary precautions to prevent a recurrence of the failure.
  6. Any damaged pipes shall be replaced.
  7. The maximum pulling load shall not exceed the load given in CS-13.3 -Table 1: Maximum Pulling Load for Trenchless Technology, nor shall it exceed the load that will stress the pipe to 50% of the material yield stress, whichever is the lower.
  8. The following additional limits shall apply:

Minimum radius        = 35m
Maximum length of drill        = 200m
Maximum pull rate        = 0.5m–1.0m per minute

Table 1: Maximum Pulling Load for Trenchless Technology

Pipe Maximum Pulling Load (kN)
63mm OD PE80 SDR11 6.9
125mm OD PE80 SDR11 26.9
180mm OD PE80 SDR11 55.7
250mm OD PE80 SDR11 107.0
315mm OD PE80 SDR11 168.7

Definitions in this section




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