Sutton Crescent Sewer Replacement

This project, with Manukau Water Limited/ Watercare Services Ltd, involved upgrading of the trunk sewer that serves the eastern most portion of “Catchment 21” within the Papatoetoe area to address historic overflows and portions of the system with reduced cover.

Fraser Thomas were engaged to undertake a detailed topographical survey and geotechnical investigation to support preliminary design, followed by a subsequent commission to provide professional surveying, engineering and consenting services through to construction completion.

The works involve installation of approximately 1.1km of new pipeline, comprising mainly 300mm diameter and also 225mm diameter Vitrified Clay pipes, and 27 manholes. It also featured the first use of PVC screw-jointed pipes for thrusting in Manukau Water projects.

Challenges included:

  • Short construction timeframe, due to delays in pipe deliveries and the amalgamation of Manukau Water and Watercare
  • Requirement to maintain live services, requiring diversion, pump over and innovative construction methods
  • Location of existing services resulted in localised inability to thrust some sections, leading to an alternative construction methodology being required
  • Dealing with some areas with poor bearing capacity soils; requiring careful attention to trenching requirements, and assessing potential effects on adjacent buildings, including developing mitigation measures where necessary.

Expertise provided:

  • Surveying
  • Civil
  • Geotechnical
  • Structural
  • Resource management planning

Project cycle:

  • Topographic survey
  • Investigations
  • Concept and preliminary design
  • Consenting
  • Detailed design
  • Tendering and contract management
  • Construction observation
  • Certification