Applicant
NZ Transport Agency
Purpose
To seek Transport Agency Board approval for the final design adjustments and construction funding for the Western Ring Route (WRR) package of projects.
Date of decision
12 December 2014
Resolutions
The New Zealand Transport Agency Board:
- approved the adjustmentsin design and forecast construction costs of SH16 and SH20 projects of the Western Ring Route, as outlined in Appendix 2
- noted that the property, design and construction cost for the SH16 and SH20, Western Ring Route, is estimated at $2.278 billion. The 95th percentile cost was originally estimated at $2.55 billion
- noted the reasons for this decision are set out in the 'Reasons for recommendation' section in Attachment.
Reason for the decision
- The scope of the project as approved by the Board in 2010 has not altered as a result of the variances covered in this report. Where the scope differs is in relation to the method used for estimating the cost of the 2010 construction funding approval.
- This revised estimate falls within the 60th percentile of the original range. The variance results from work that meets the scope approved by the Board in 2010, and has been through a thorough 'value for money' design review process.
- The WRR design and cost variance has been assessed against the Transport Agency's Assessment Framework. The assessment profile for the project remains as: high strategic fit, high effectiveness, medium efficiency. The BCR of the whole WRR is 3.0.
- The project was originally assessed with a high effectiveness rating. This has been enhanced further given the safety, operational, and whole-of-life improvements. An example of this is the final design of the Waterview interchange where the configuration of the ramps was changed to meet operational reviews.
- The forecast costs given in this report are based on a higher degree of design detail and understanding of risk than was available at the time of the original approval. It is envisaged that they are not likely to be exceeded for the remainder of all the works.
- We confirm that the matters in sections 20(2) and 20(5) of the LTMA have been satisfied, and that the matters in section 20(3) have been taken into account.
