The construction companies behind Transmission Gully are suing Waka Kotahi over the roading project, which remains unfinished.

While the road is open, the project is still incomplete after missing multiple opening dates and has exceeded its initial $850 million budget. 

Waka Kotahi claimed there's a clear disagreement about the outstanding work and standards that need to be met to complete the project- aligning with the contract.

Infrastructure NZ CEO Nick Leggett says problems and miscommunications were present throughout all the stages of this project.

"This is the lesson from Transmission Gully- we need to build more, we've got a massive $200 billion infrastructure deficit. We've got to be better at renewing the assets we've got."

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