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  2. General
  3. Infrastructure Development Processes
  4. Quality Assurance Information Requirements
    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
      1. T601-Manhole - Standard
      2. T602-Manhole - Shallow
      3. T603-Manhole - Ladder and Steps
      4. T604-Manhole - Precast 1050mmØ Lid
      5. T605-Manhole - Entry Fixing
      6. T606-Manhole - Standard and Raised Access Detail
      7. T607-Manhole - Inclined Access Detail
      8. T608-Manhole - Internal Drop
      9. T609-Manhole - External Drop
      10. TT610-Manhole - PE Pipe Connections - Wall Adapter and Pre-Cast Manhole
      11. T611-Manhole - PE Pipe Connections - Stub Flange and In-Situ Base
      12. T612-Manhole - PE Pipe Connections - Electrofusion Coupler and In-Situ Base
      13. T613 Manhole - PE Pipe Connections - Puddle Flange and Pre-Cast Manhole
      14. T614-Manhole - Access Detail in Carriageway
      15. T620-Rodding Eye - Shallow < 2.5m
      16. T621-Rodding Eye - Deep > 2.5m
      17. T630-Property Connection - Standard
      18. T631-Property Connection - Depth > 2.5m
      19. T632-Property Connection - Within Property
      20. T633-Property Connection - Outside Property
      21. T634-Property Connection - Entry to Wastewater Main/Manhole
      22. T637-Lateral Connection - Single Connection to Manhole
      23. T638-Lateral Connection - Two or More Connections to Manhole
      24. T639-Lateral Connection - Single Connection to Main
      25. T640-Lateral Connection - Two Connections to Main
      26. T641-Lateral Connection - Two Adjacent Connections to Main
      27. T642-Lateral Connection - Rear Lot Connection
      28. T643-Mains Connection - Saddle Connection
      29. T651-Bedding and Backfill Details
      30. T652-Anti-Scour Block and Trenchstop
      31. T653-Buildings Near Public Mains
      32. T654-Close Proximity - Retaining Wall Restrictions
      33. T660-Pump Station - Typical Site Layout
      34. T661-Pump Station - Elevation Section
      35. T662-Pump Station - Plan Section
      36. T663-Pump Station - Pedestal Base Plate, Pedestal Mounting, Valve Chamber and Riser Connection
      37. T664-Pump Station - Deflector Plate, Ladder and Plinth
      38. T665-Pump Station - Valve Extension Spindle, Spindle Guide and Handwheel
      39. T666-Pump Station - Cover Slab
      40. T667-Pump Station - Frame
      41. T668-Pump Station - Chamber Lid
      42. T669-Pump Station - Chamber Lid Padlock and Handle
      43. T670-Pump Station - Rising Main Entry to Receiving Manhole
      44. T671-Pump Station - 25mm Water Service Connection
      45. T672-Pump Station - Electrical - Standard 2 Pump Stn Without Soft Starters (1 of 2)
      46. T673-Pump Station - Electrical - Standard 2 Pump Stn Without Soft Starters (2 of 2)
      47. T674-Pump Station - Electrical - Standard 2 Pump Stn SMC - 3 Soft Starters (1 of 2)
      48. T675-Pump Station - Electrical - Standard 2 Pump Stn SMC - 3 Soft Starters (2 of 2)
      49. T676-Pump Station - Electrical - Standard 2 Pump Stn IMS2 Soft Starters (1 of 2)
      50. T677-Pump Station - Electrical - Standard 2 Pump Stn IMS2 Soft Starters (2 of 2)
      51. T678-Pump Station - Electrical - Standard 2 Pump Stn ISMC - 3 Soft Starters (1 of 3)
      52. T679 Pump Station - Electrical - Standard 2 Pump Stn ISMC - 3 Soft Starters (2 of 3)
      53. T680-Pump Station - Electrical - Standard 2 Pump Stn ISMC - 3 Soft Starters (3 of 3)
      54. T681-Electrical - 2 Pump Stn Mincas SMC-3 Soft Starters (1 of 2)
      55. T682-Electrical - 2 Pump Stn Mincas SMC-3 Soft Starters (2 of 2)
      56. T683-Pump Station - Electrical Cabinet
    9. T700 Water Supply
      1. T700-Water Supply Pipe Hierarchy
      2. T701-Water Supply - Looped and Linked Principal Mains
      3. T705-Water Main - Location at Intersections
      4. T706-Watermain - Location at Cul de Sac
      5. T707-Water Main - Rider Main to Main Connection
      6. T708-Water Main - Flushing Point
      7. T709-Water Main - Branch Valves and Hydrant Combinations
      8. T710-Water Main - Support for Asbestos Cement Main
      9. T713-Hydrant Surround
      10. T714-Hydrant Box
      11. T715-Hydrant Surround Blocks
      12. T716-Valve Surround
      13. T717-Valve Box
      14. T718-Valve Surround 75mm Concrete
      15. T719-Valve Surround 100mm Concrete
      16. T720 Valve Surround Heavy Duty Concrete
      17. T721-Anchor block for Sluice Valves on Mains
      18. T722-Anchor Block for Flanged Fittings on Mains
      19. T723-Thrust Blocks
      20. T724-Hydrant and Valve Marker Post
      21. T727-Water Meter - Type 1 and 2 Point of Supply Location Installation
      22. T728-Water Meter - Type 3 and 4 Point of Supply Location Installation
      23. T729-Water Meter - Fire System Connection With Potable Supply Installation
      24. T730-Standard 20mm Manifold Connection
      25. T731-Standard 20mm Manifold Connections - Plan View
      26. T732-Multiple 20mm Installations
      27. T733-20mm Connection Requiring Double Check Valve
      28. T734-20mm Connection Requiring RPZ Installation
      29. T735-25mm, 40mm or 50mm Meter Installation With Double Check Valve
      30. T736-<50mm Meter Installation with RPZ
      31. T737-Property Connection - 50mm Combination Meter Installation with Double Check Valve
      32. T738-Combination Meter Installation with RPZ
      33. T739 >50mm Combination Meter Installation with RPZ & Bypass Option
      34. T740-Property Connection - Secure Connection
      35. T741-Manhole - Class A Loading
      36. T742-Chamber - Class A Loading
      37. T743-Manhole - Class B Loading
      38. T744-Chamber - Class B Loading
      39. T751-Bedding and Backfill Details
      40. T753-Buildings Near Public Mains
    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

DS-10 - Appendix H - Geotechnical Requirements Summary 

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DS-10 - Appendix H.1  General

The following table summarises the geotechnical reporting requirements at each stage of the development process:

Table 1: Geotechnical Reporting Summary Table

Stage Report Purpose Typical Investigation Type Typical Document Provisions Comment
Stage 1. Resource Consent (Subdivision) Development Evaluation Report

Identify:
- Natural Hazards.
- Development Constraints.
- Appropriate Stormwater Management.
- Appropriate Wastewater Management.

Confirm:
- Land is suitable for the proposed landform, density and use.
- Safe access is possible.

- Proposal review

- Aerial photograph review

- Geological map review

- Site walkover

- A limited geotechnical assessment

- Sufficient investigation to fully assess all hazards 

- Infill subdivision may only need 2 hand augured boreholes or test pits to 2m deep.  Larger subdivision will need more tests, likely deeper tests especially if liquefaction possible.

- Regardless of scale of subdivision, liquefaction, stability and settlement risks shall be quantified.

- Overview of constraints

- Considerations for landform design (i.e. max cut / fill heights and grades)

- Preliminary assessments of stability, settlement and liquefaction

- Recommendations for additional assessments

- Statement of Professional Opinion (per 4402)

- For infill or very small subdivisions, on land with no geotechnical issues and where no earthworks are proposed, it may be appropriate to proceed to Stage 4 at the completion of Stage 1. 
Where this is the case, additional detail regarding foundation requirements is likely to be necessary.

- In cases where works are required to create safe & stable building areas or access, these shall be undertaken as part of the subdivision works so that there is a suitable area when titles are issued, Stages 2 and 3 are then applicable.

- If further subdivision of an existing lot (or lots) is proposed, additional Geotechnical assessment is required.  Refer to original report author for comment.

Stage Report Purpose Typical Investigation Type Typical Document Provisions Comment

Stage 2. 

Development Works approval

Development Works Approval

- Address information gaps from Stage 1.

- Connect the requirements of Stage 1 to the provision of infrastructure.

- Detailed design of all engineering and servicing issues.

Investigation and analyses for:
- Geotechnical issues.
- Earthworks.
- Infrastructure issues.
Provision of detailed design and calculations for:
- Geotechnical issues.e.g. retaining walls, embankments, slopes etc.
- Infrastructure issues e.g. pipes, roads etc.
 
Stage 3.
Final Sign Off (224)
Geotechnical Completion Report (GCR) - Confirmation that all Geotechnical requirements from Stages 1 and 2 have been met.

- Observations, Testing and Monitoring during the development. 

- Additional testing as determined by the certifying engineer.

- Summary of works undertaken
 
- Testing and monitoring records

- Statement of land suitability 

- Recommendations for Building Consent phase 

- As-Built Information of the finished landform and any structures.

- Individual Lot Summary table

- Statement of Professional Opinion (Form G2 or per 4431)

- Confirmation that RC Conditions have been complied with
- Limitations on the applicability of the recommendations.

- A Geotechnical Completion Report
 certifies that the finished landform is safe and stable.

- It may state foundations can be designed to NZS3604, however earthworks proposed in Building Consent phase may excavate deeper than the testing or fill deeper than 600mm, therefore specific investigation is required.

- Although NZS3604 requires 4 tests per lot the number of tests required can be less than this, depending on the volume of earthworks, the type of test, the number of lots and the variability of the ground.  

- DS-10 recommends a minimum of two tests per lot, (minimum 2m deep) with at least one of these tests extending at least a metre below the likely depth of foundation.       

Stage 4a.
Building Consent (where GCR or other existing site specific report is available)
Engineering Assessment Report Provide the Building Consent Authority sufficient information that there is reasonable grounds to conclude that the:
- Site works
- Foundations 
- Retaining walls
- Soakage systems
and the like, will comply with the Building Code and recommended outcomes within the IDC.

If:
- Building outside the nominated building platform
- Retaining walls and/or earthworks are proposed
then a geotechnical plan review and/or a geotechnical report will be required.

Additional investigations requirements are likely to be limited unless:
- Otherwise defined in the GCR
- The national standards have changed since the report was prepared 
- The testing was not sufficient for the proposed site development.

Where the GCR is older than 7 years: 
- A review is required to confirm no additional earth works have been completed and to check for other changes either on ground or in legislation since that time.

If the GCR was written prior to Dec 2012 and liquefaction is a possible risk, an assessment of liquefaction risk shalld be requested.  

Where a GCR is older than this and liquefaction was assessed, the original author shall be contacted to confirm the appropriateness of their recommendation in light of more recent developments.

If further subdivision of an existing lot is proposed, additional Geotechnical assessment shall be required. Refer to original report author for comment.

- If the only requirement is inspection or testing of cleared ground by an engineer, a letter confirming an engineer has been engaged for that work shall be supplied.

- Geotechnical plan review (unless 3604 applies) suggests
"unless complaint with existing report”.

- Results of any testing (if required).

- Refreshed GCR (where applicable) or geotechnical design report or geotechnical assessment report.

- Requirements for temporary works /  protection of other property.

- Geotechnical design report or geotechnical assessment report.

- Schedule of inspections required (if applicable).

- Where earthworks exceed the limits in DS10, a plan review by a Geo-Professional is required.  

- The GCR shall define the limits beyond which a Geotechnical review (and/or design inputs) is required.

Additional investigations are required where: 
- Specific design requirements are recommended in the GCR.
- National Best Practice Standards have changed since the report was prepared.
- The proposed design method is not supported by the content of the GCR.

This typically would include the requirements of the Joint MBIE/NZGS Geotechnical Engineering Guidance, Modules 1 – 6 that are summarised in Councils Ground Checks Guideline.

- Depending on location, proposal and  potential hazards, an accredited Geo- Professional may be required.  

Stage 4b.
Building Consent (where GCR is not available)
Engineering Assessment Report Provide the Building Consent Authority sufficient information that there are reasonable grounds to conclude that the completed:
- Site works
- Foundations 
- Retaining walls
- Soakage systems 
and the like, will comply with the Building Code and the approved plans.
Requirements will vary depending on:
- Proposed site works
- Proposed foundations
- Proposed retaining walls
- Underlying geology
- Possible hazards

- Site specific testing.

- Interpretation specific to the proposal.

- Recommendations for:
- Foundation design
- Site works
- Retaining walls
- Discharge locations / rates 
- Temporary works 
- Protection of other property 

- Geotechnical design report or geotechnical assessment report

- Schedule of inspections required

- A full Geotechnical report is required in this instance. 
This typically would include the requirements of the Joint MBIE/NZGS Geotechnical Engineering Guidance, Modules 1 – 6 that are summarised in Councils Ground Checks Guideline.


- Depending on location, proposal and potential hazards, an accredited Geo- Professional may be required.  

Stage 5.
Building Consent Code Compliance
Certificate
  Provide the Building Consent Authority sufficient information that there are reasonable grounds to conclude that the completed:
- Site works
- Foundations 
- Retaining walls
- Soakage systems 
and the like, comply with the Building Code and the approved plans.

Inspections and testing of site works and foundation, retaining wall construction

Building Consent documents will specify if inspection by an appropriately accredited Geo-Professional is required.

- Summary of inspections undertaken.

- Test results

- Plan of locations 

- Fill certification per NZS 4431 (where applicable)

- As-Built Information of any changes to the approved plans 

PS4 Producer Statement (where applicable)

- The PS4 is a supporting document.  

- The emphasis is on inspection records and testing.

 

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