Maritime New Zealand says another container from the wrecked ship Rena has washed ashore on rocks near Bowentown in the Bay of Plenty.
The container ship has been stranded on Astrolabe Reef off the coast of Tauranga since 5 October last year.
The ship broke in two during severe weather a fortnight ago and about three-quarters of the stern slipped below water last Tuesday.
Fifty-two of the estimated 150 containers that came off the wreck on 7 January have been recovered from beaches. Another 18 have been located on the shoreline or in the water.
Maritime New Zealand says a leaking protective boom placed at Maketu has had to be repaired, but no oil has entered the estuary.
Divers on Monday continued to assess the condition the ship but the authority says they will not go into the hold until it is safe.
Conditions are expected to improve and swells will drop to about one metre by Tuesday, it says.