Canterbury District Health Board has lifted health warnings at two of Christchurch's most popular water sport locations.
Tests have shown decreased bacteria levels at Lyttelton Harbour and Taylor's Mistake Bay, meaning they're safe to use for the first time since the 22 February earthquake.
However Canterbury Medical Officer of Health Dr Alistair Humphrey says people should still stay away for at least two days after any heavy rainfall, because of the possibility of further contamination.
Health warnings are still in place for many of Christchurch's rivers and beaches because of the damaged sewerage system.
The exception is for tourist company Punting on the Avon, which is permitted to operate on a stretch of the river considered safe.
The health board says every effort has been made to ensure people taking part in this activity are safe.