The South's tsunami Sunday

Up to 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 dangers yesterday in the wake of nation-wide tsunami alerts.

A tsunami advisory remained in place for New Zealand overnight after the Ministry of Civil Defence and Emergency Management downgraded an earlier Pacific Tsunami Warning Centre warning for New Zealand.

The advisory will be reviewed at 8am today.

The original warning for New Zealand, which followed an 8.8 magnitude earthquake near Chile on Saturday that killed at least 300 people, was cancelled yesterday afternoon.

The earthquake struck off the coast of Chile about 7.30pm New Zealand time, tearing apart houses, bridges and highways and sending the tsunami racing across the Pacific at speeds of up to 700kmh.

Late yesterday, wave action of up to 1m continued to show on tidal gauges across the east coasts of the North and South Islands and the Chatham Islands without any indication of that height decreasing, the ministry said.

The Chatham Islands and Banks Peninsula could still expect waves of 1m-3m.

"Scientific advice is that there is still a likelihood of surges and rapid sea level changes over the 24 hours after the initial wave arrivals," the ministry said.

"Wave heights could be larger than what we have currently experienced."

Strong currents could be expected in harbours and restricted waterways.

Dunedin police closed city beaches about 9am yesterday, shortly after the Otago Daily Times was told by Dunedin City Council civil defence manager Neil Brown there was no risk to the city.

Dunedin police emergency response commander Inspector Alistair Dickie yesterday said about a dozen police, as well as volunteer fire officers and surf lifesavers, patrolled beaches between Taieri Mouth and Waikouaiti warning people of the tsunami risk.

Mr Brown had told the ODT about 8am: "I would be very surprised if anything was noted on the shoreline here.

From very early on it was obvious the risk to Dunedin was nil," Mr Brown said.

Clutha District Civil Defence controller Charles Hakkaart said the council issued a partial alert at 1.30am and continued monitoring the situation with police and the fire service.

About 11am, people were "actively encouraged to evacuate" from very low-lying areas such as Toko Mouth and Pounawea, while flooding signs were erected around the Nuggets, Newhaven, Jacks Bay, Catlins Lake and Hina Hina.

Cathedral Caves was closed to the public.

Most people accepted the recommendation to leave.

"One or two people ignored that and walked along the beaches, but that's always going to happen - 99% took the advice," Mr Hakkaart said.

Residents were allowed to return home after 3pm when it became evident waves were not getting above the expected high tide level.

Sixty campers at the Hampden Beach Motor Camp, in North Otago, were evacuated by camp management from about 7am due to the alert.

Later in the morning, campers were given 15 minutes to return to the camp and collect their gear.

Fireman Bob Williams was full of praise for the camp owners, Gary and Hilda Liddall, who made the decision to evacuate.

Mrs Liddall said nearly 60 people were in the camp, which is at sea level beside the beach, and people started leaving from 7am.

Most went up the hill to wait it out.

Warrington beach and camping area on Warrington Domain were evacuated about 8.30am.

Lifeguards declared a "no swimming" status for the day.

On Otago Peninsula, up to 500 residents on low-lying areas received personal warnings yesterday afternoon from police, firefighters and coastguard personnel.

With a 2.3m spring tide mid-afternoon, there was concern surges of water from the tsunami could result in flooding on Portobello Rd and Harington Point Rd.

Portobello police officer Senior Constable Lox Kellas said all residents from Taiaroa Head to Harwood had been warned of the risk from the tsunami, as had golfers at the Otakou Golf Club, and people parked near the harbour in campervans.

The coastguard vessel was pressed into service to post notices at Allans beach and Sandfly Bay, and warn vessels in the area of the situation, and Pilots beach was closed.