Mr Stolwerk urged Northlanders to refresh their understanding of the tsunami risk and evacuation routes.
"All of New Zealand's coastline is at risk of tsunami, and given that so many Northlanders love spending time on the coast, it's important to spend some time learning how to reduce that risk," he said.
First and foremost was knowing the natural warning signs of a local source tsunami which could arrive without time for any official warning.
"If people are on the coast and experience a long or strong earthquake, change in sea level or loud or unusual noises coming from the sea, they should move inland or to high ground without waiting for further information," Mr Stolwerk said.
"It's also a good time to think about aspects such as having multiple alerting options and sources of information, and how to let friends and neighbours know in the event of a tsunami warning."
The free Hazard app for smartphones and the Civil Defence Northland Facebook page were examples of alerts options and information sources.
Meanwhile, Northland's network of 171 tsunami sirens remains the largest in New Zealand and is expanded every year.
Additional budget was allocated this year after last November's Kaikoura earthquake and the consequent tsunami warning.
The new maps are at www.nrc.govt.nz/evacuatenow and the Hazard app www.nrc.govt.nz/cdalert.