A major Coromandel highway's closed indefinitely after chunks of road were swept out to sea in this week's storm.

READ MORE: Weather Watch - Gales still severe as clean-up begins

Seven crews are working to repair the Thames Coast Road, State Highway 25, with the hope of opening one lane as soon as tomorrow.

Agency System Manager Karen Boyt says it's unclear when it'll be fully open again.

"In some sections the pavement has been damaged significantly, right through the two lanes. So there is a lot of work to be done."

A residents-only vehicle convoy is being organised to get people back to their properties.

Ms Boyt said crews are working to repair the areas where the seawall's been torn off.