It was an exercise based on an 8.9-magnitude earthquake in Peru creating a tsunami with waves up to 5m high on Otago's coastline.
Dunedin City Council Civil Defence manager Neil Brown said the scenario was part of operation Tangaroa, a nationwide exercise which allowed Civil Defence staff to practise their tsunami response system.
"This exercise is totally different from other exercises we've done because the scenario has been given to us by Civil Defence in Wellington.
"They are running the exercise and throwing situations at us, so we don't know what's going to happen next."
About 100 people from a wide range of organisations participated in the exercise, which involved a simulated evacuation of residents living near the beach in South Dunedin and other low-lying communities on the Otago coastline.
Mr Brown said it was important to rehearse responses to warnings of tsunamis, particularly when New Zealand was vulnerable to them.
In February this year, about 200 South Otago residents moved to higher ground, 60 campers at Hampden were evacuated, Dunedin beaches were closed and about 500 people on the Otago Peninsula were personally warned about possible tsunami dangers after an 8.8 magnitude earthquake in Chile.
The result was unspectacular, with waves of about 1m reaching the Otago coastline.
"Today's exercise all went as planned. We always learn something from an exercise.
"When we get curly things thrown at us, we learn from them and make improvements," Mr Brown said.
