An independent panel is finding holes in Auckland Council's proposed 30-year Unitary Plan.

It's found the plan doesn't define key concepts, like infrastructure and development.

That's raised questions about plans to protect tertiary institutions, and grow the Ports of Auckland.

Panel chairman Environment Court Judge David Kirkpatrick says the process is rigorous and thorough.

"It's always good to start. It's even better to make a start and realise that the processes that have been put in place are working and that's where we're at right now."

The panel is sifting through a million submissions over two years.