The effect of ex-Tropical Cyclone Debbie continued to be felt as the system tracked across the Tasman Sea in the first days of April, bringing persistent heavy rain to the Bay of Plenty area on 4-5 April. Over 200 millimetres of rainfall was recorded in places.
Recorded rainfalls on 4 April included:
- Whakatāne – 137 millimetres – wettest April day recorded since 1952
- Te Puke, Western Bay of Plenty – 186 millimetres – wettest April day recorded since 1973.
The town of Edgecumbe was inundated when a stopbank (levee) on the Rangitāiki River failed on the morning of 6 April. It was estimated at the time that the flow in the river exceeded the design parameters of the stopbank by 30 per cent. Fast-flowing water entered the town, large parts of which lay below the level of the river. An order to evacuate the town followed, affecting some 580 households and a population of approximately 1,600 people.
Police and fire crews made house-to-house searches to ensure no one remained trapped, and boats were used to rescue residents in some areas. Resupply operations also had to be undertaken in the Whakatāne district by helicopter as up to a further 2,000 people were cut off by the floodwaters.
Damage to properties in the area affected by the floods was worsened by the speed of the water flowing through the breached Edgecumbe stopbank. Hundreds of properties were inundated; about 70 per cent of the town was said to have been affected. Of those, around 10 houses were assessed to be beyond repair. About 170 residents were able to return home by 14 April: as at May 2017, it was estimated that around 100 homes were still uninhabitable due to flood damage.