Thursday, February 18, 2010

City makes some decisions on the Bridge

We are not going to have a quick referendum, this is good as I do not think that it would have passed. The City staff have given the council this report.

From what I heard from the Mayor on the radio with Adam Stirling, I have to say he seems to be going to the extent that I wanted the city to go with the bridge project.

There is discussion of what seismic standard to work towards with the bridge. What I find interesting is that the Point Ellice Bridge is not expected to be usable after a 6.5M earthquake. The recommendation to council is to go foward with a plan for a bridge that could withstand an 8.5M earthquake - a lifeline bridge.

I am not convinced this makes any sense as the land on either end of the bridge would be in significant danger of major problems in such a large earthquake. Certainly the buildings of Old Town would seal off all the streets in the Old Town and therefore allow for no access to the bridge. In an 8.5M event, the whole Dockside Green area will suffer from liquefaction.

Whatever option the City decides to go forward I would hope that the City does not forward unless they have a Class A estimate for the bridge project and has a mechanism in place to ensure the project can not go over budget. We are still working with a Class C estimate for replacement and Class D for refurbishment. Neither one of them is appropriate to move forward with on a project.

Going forward on the basis of a Class C estimate was completely and utterly inappropriate of the City.

From one definition of a Class C estimate:

Class C Estimate

  • General Description

    • Ballpark estimate used only in preliminary discussion of feasibility
    • Sufficient for selecting correct investment decisions
      • But not used for making commitments
  • Includes

    • Completion of all work necessary to undertake preliminary design
    • Knowledge of site conditions adequate to enable identification of site related risks, and
      • Development of corresponding contingency costs
    • Expected precision variance -15% to +25% or more

Here is a page that explains the different classes of estimates.

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