Several of the quakes hit between 4:08am and 4:39am.
It will give emergency services better access to the area.
Volunteers sprung into action when a person driving past shouted out their window that someone had capsized.
Their car plunged into the lake near a well-known dive spot.
Divers will conduct an underwater search for the vehicle.
Emergency services were called about 9am.
All crew aboard the vessel are unharmed, Maritime NZ confirmed.
A driver of a bus that crashed, killing five people, has pleaded guilty to 13 charges.
The person was found dead at the scene.