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    1. QA-1 Resource Consent Application Requirements
    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-20.4 Subgrade Preparation


  1. The exposed subgrade (excavated to trial subgrade level or footpath depth) shall be tested by using a Scala Penetrometer for compliance with the following CBR values:
    1. In footpath and traffic island infill: CBR value >7 (3 blows/100mm)
    2. In vehicle crossing and kerb and channel areas: CBR value >10 (4 blows/100mm)

Scala penetration results shall be converted to CBR utilising Austroads 2008 Guide to Pavement Design Fig: 5.3.

  1. If the material fails this initial test then either:
    1. The existing subgrade shall be further compacted if the material is suitable, to improve the CBR value.
    2. The unsuitable material shall be excavated and removed from site, and replaced suitable granular fill compacted up to the trial subgrade level.
  2. When treatment b-ii) is required, the excavation shall extend 100mm past either side of the edge boards, or the outer limits of the construction area:
    1. The depth and extent of this subgrade excavation shall be as instructed by the Engineer.
Explanatory Note:
Small pockets of material may require treatment rather than the entire subgrade area.
  1. All backfill shall be compacted in lifts of not more than 100mm.
  2. The subgrade area, either existing or reinstated, shall be trimmed and shaped to accommodate the specified lines and levels given and compacted to provide uniform support for the pavement course.
  3. All tree roots found in the subgrade or pavement area during excavation shall be removed. They shall be severed 500mm outside the final edge alignments, removed from site and legally disposed of. Any root greater than 50mm in diameter is to be cleanly sawcut. No such roots shall be cut without the prior approval of the Engineer if they are within the drip line of the tree.

Definitions in this section






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