The Rangitaiki River breached through a stopbank yesterday, forcing 2000 residents to evacuate as their homes were swamped in a muddy deluge.
More evacuations in Edgecumbe and neighbouring areas were ordered this morning as water made its way through the town and down to the coast.
"What the water's doing is finding the easiest path and a lot of the [area] is under sea level," Bonne said.
River levels dropped by 600mm this morning and had continued to drop throughout the day though water was still flowing through the town.
"Regional council is hoping to start a blockage early this afternoon."
This afternoon Bonne was on his way with East Coast MP Anne Tolley to meet local Tuhoi iwi, who had strong networks of support operating in the region.
Parts of Ruatahuna and Ruatoki were still isolated and food and medical supplied had been delivered to those still holed up in cut of places.
Bonne said reports of looting were false and he was disappointed untrue Facebook posts had upset people.
Edgecumbe was well secured by police and security guards, he said.
More than 2000 people were cut off across the region this morning as it remained inundated by flood waters.
It was estimated it could be another day until the floodwater in Edgecumbe drained.
River levels are dropping but the town is still likely to be under water a day after the Rangitaiki River breached its banks, officials say.
On Thursday police and the fire crews went house to house searching for anyone needing help evacuating, while welfare centres were set up at the Firmin Lodge in Kawerau and at the Whakatane War Memorial Hall.
Boats were also used to rescue some residents in areas that couldn't be reached by trucks.
Prime Minister Bill English visited the area this morning to assess damage.
On Thursday efforts were being organised to supply vital medical and food supplies to the stricken residents of Ruatahuna, Minginui, Waimana and Ruatoki, Whakatane District controller Barbara Dempsey said.
These would be flown in by helicopter today.
Around 1600 people were cut off in Waimana and Ruatoki while a further 600 are stranded in Ruatahuna and Minginui.
Dempsey said around 100 people stayed in evacuation centres throughout the district with most people finding alternative places to stay after they were forced out of their homes yesterday.
"They're in their homes but they have floodwater around them so we're trying to get supplies to them," she said.
Meanwhile engineers were monitoring stop banks and finalising plans to repair the catastrophic breach.
The council was working with Transpower to reduce the discharge from the Matahina Dam and operations were underway to pump out flooded farmland.
Waterways in the eastern Bay of Plenty were monitored through the night, with the Rangitaiki River the main concern.
Council staff say they have put measures like piles of rocks on the shoreline in place, and will be able to judge their effectiveness at first light.
They've been keeping an eye on a few areas of seepage, and are hoping they have eased overnight as waters recede.
The council says water is still coming through the breach on College Rd in Edgecumbe.
It will be able to assess it better as the water level lowers, and is hoping to put a temporary stop-gap in place over the weekend.
The council has used storage capacity at Matahina Lake to reduce the river flow by about 12 per cent.
Meanwhile the Whirinaki Bridge, between Murupara and Galatea, was closed last night due to flood damage.
People in Taneatua are being asked to reduce waste water by flushing their toilets as little as possible, and limiting showers and baths, due to issues with the sewerage system.
- Additional reporting Newstalk ZB
