City Rail Link cost concerns have uncovered a reoccurring issue with New Zealand infrastructure projects. 

The project's former boss Sean Sweeney has claimed the project could've cost half of its estimated $5.5 billion price.  

This sparked Infrastructure Minister Chris Bishop to announce a full review of the project after its open date later this year.   

Infrastructure NZ CEO Nick Leggett told Ryan Bridge we're not approaching projects right, from the start. 

He says we don't have the proper controls and take too long to plan, so things drag on. 

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