In addition to the government’s review, here is Auckland Council’s full review of the CBD Tunnel - http://transportblog.co.nz/wp-content/uploads/2011/05/City-Rail-Link-Summary-Report-13-May-2011.pdf
The executive summary:
Historically, a range of proposals have been developed for a rail tunnel through the Auckland city centre. In 2010, a preferred route for a tunnel, the City Rail Link, was identified and work commenced on a concept design and Business Case to support designation of the route. In November 2010, Auckland Transport (AT) and Auckland Council (AC) in partnership with KiwiRail Group (KRG) presented the case for the City Rail Link to the government for its consideration.
The Minister of Transport (MoT) requested a review of the City Rail Link (or CBD Loop) proposal. That Review has been undertaken over the last 5 months and its report is expected to be released shortly.
The government led Review has provided AT and AC with an opportunity to further review the assumptions, refine the costs and benefits, and identify the further work needed to secure funding for the City Rail Link. All of this work has been made available to the government led Review team and the same material used to prepare this report.
The Review confirmed that the costs of constructing and operating the City Rail Link are accurately estimated, with a small increase in operating expenditure arising from new information which became available after the original Business Case was completed.
There was, however, a wide disparity between the benefits assessed by the MoT/Treasury Review compared with those estimated as part of the AT and AC update. This is largely due to the lower transport benefits assessed as part of the government led Review.
AT and AC consider that, taking into account the wider transport policy initiatives which are planned, the City Rail Link would deliver overall benefits exceeding overall costs, with the benefit cost ratio ranging from 1.1 to 2.3 (BCR = 1.1 to 2.3).
While there are differences between the findings of the government led Review and the AT/AC update, AT and AC and their advisors are strongly of the view that the overall evaluation results are sufficiently robust to justify the immediate commencement of the designation process, particularly as the CRL is economically justifiable in terms of its transport related benefits alone. This process needs to commence as soon as possible to minimise the potential for any development to increase costs, delay the project, or even prevent its implementation.
AT and AC acknowledge that, in line with all major project development programmes, more work needs to be done to further develop the case for funding of the City Rail Link. This work will take full account of central government‟s requirements for the development of public sector funding requests.
In addition to progressing with this work, this report recommends that the Auckland Council resolve to immediately commence the process to secure and protect the route of the Auckland City Rail Link.
This summary report presents AT and AC‟s key findings arising from participation in the government led Review of the City Rail Link project.
Let’s hope the council releases all their background documentation shortly, and that MoT do the same. It will be good to pin-point exactly why the two review differ so hugely.